Heat Pumps - post here.

Rushy Fields

Hi all,
I have a NIBE 1145 GSHP in utility and want to turn off heat.....
The scheduling is on at the moment Shedule 1 is 00:00 to 07:00am 20C. Schedule 2 is 17:00 to 19:00 20C. Using Heating curve 0.
Do i just disable the scheduling o do i have to change some other settings?
Hot water heating is at normal setting and is Prioritized at 5am to 7am if required.
I was thinking of maybe changing the heating curve also......

Any Advice welcome.

Thanks

KCross

Rushy Fields wrote: »

Hi all,
I have a NIBE 1145 GSHP in utility and want to turn off heat.....
The scheduling is on at the moment Shedule 1 is 00:00 to 07:00am 20C. Schedule 2 is 17:00 to 19:00 20C. Using Heating curve 0.
Do i just disable the scheduling o do i have to change some other settings?
Hot water heating is at normal setting and is Prioritized at 5am to 7am if required.
I was thinking of maybe changing the heating curve also......

Any Advice welcome.

Thanks

The system will automatically turn off space heating once the 24hr outdoor temp average goes above a set value.

You can change that cutoff point via the menu. Off the top of my head, its in a menu called "auto mode setting" and its a degrees celsius figure you are looking for (something like "stop heating"). Reduce that value to cause the system to turn off space heating sooner. I have mine set to 13C so once the average outdoor temp over a 24hr period exceeds 13C the system will turn off space heating automatically and continue to heat hot water.

And obviously, when it gets cooler later in the year it will automatically come back on.

I wouldn't mess with the heat curves or other settings. Just get that cutoff temp set to your liking and then the system doesn't have to be messed with twice a year.

Rushy Fields

KCross wrote: »

The system will automatically turn off space heating once the 24hr outdoor temp average goes above a set value.

You can change that cutoff point via the menu. Off the top of my head, its in a menu called "auto mode setting" and its a degrees celsius figure you are looking for (something like "stop heating"). Reduce that value to cause the system to turn off space heating sooner. I have mine set to 13C so once the average outdoor temp over a 24hr period exceeds 13C the system will turn off space heating automatically and continue to heat hot water.

And obviously, when it gets cooler later in the year it will automatically come back on.

I wouldn't mess with the heat curves or other settings. Just get that cutoff temp set to your liking and then the system doesn't have to be messed with twice a year.

Thanks for the info KCross will have a look at the system when i get home later

top_dog

Hi all,
I have an old stone two-story farm house which I am going to get renovated. I currently have an oil boiler with rads and it's very expensive to heat house currently and actually doesn't heat house adequately in cold weather. There is poor quality windows and roof insulation. I plan to upgrade windows and roof insulation. But just lime plaster the walls. 
I am thinking that if I go with UFH with a2w or ground heat pump the stone walls and the screed will provide good thermal mass and would be the best option for heating house.
I have been told by the experts that the a2w and ground are very similar with regards to efficiency. They also say that you need good insulation which I may not have in the walls. Although the walls are more than two feet thick so they should have good thermal mass. 
I read online though that ground has a better SPF value. In this example with stone house what would be the best option? Ground or a2w? I would run the heat pump on nighttime rate electricity. I believe the lower the outside air temp the less efficient the a2w heat pump? Therefore my feeling is if I am running at nighttime rate elec I would be better to go with ground as it would have a better COP at nighttime. Would anyone agree with this? 
I hope to hook up the oil boiler as a backup as I currently have oil boiler. Does anyone recommend doing this?
If you don't think that an a2w or ground source heat pump is suitable for this house I'd be interested to know what heating system you think is suitable? 
Any advice would be very welcome. Thanks!

I have an efel oil stove and the heat out of it is unreal. One that heats the rads and one in the sitting room and you'll have all the heat you'll ever need and they're very efficient. There are idiots getting rid of them for much more expensive solid fuel and I highly recommend the oil stoves and you can get them cheap as chips 2nd hand as no one seems to want them any more.

Heat pumps are grand but you need a very well insulated and air tight house which is expensive to obtain and heat pumps are a huge cost and if it dies out of warranty you are screwed and they have a certain lifespan of around 10 years this is ridiculous. IF you could get a heat pump for the cost of an oil boiler then I'd say everyone should have one but until then I wouldn't dream of a heat pump heating system. I know others will completely disagree but each to their own.

Definitely insulation is always best and then use the oil stoves. I guarantee you would not regret it.

Water John

Certainly start with good windows, doors and attic insulation.
The heating system is, in many ways, down to personal choice, cost and future proofing.
Ground source heat pump (GSHP) is a bit more efficient but depends on your site and soil, also dearer.
A2W is generally a plug and play unit. The use of night rate electricity will more than offset the slightly lower efficiency of night operation.
Both are usually matched with UFH. For that you will need to dig out floors at least 300mm.
Certainly, oil system is cheap, in capital terms.
I think, it will be subject to some emissions type penalty, in the not too distant future.

Personnally, I would look at A2W, along with UFH and a timber stove.

top_dog

Water John wrote: »

Ground source heat pump (GSHP) is a bit more efficient but depends on your site and soil, also dearer.

Sorry just had a query on this as I have read this also. Technically I don't understand how the ground source heat pump is more efficient than a2w? In summer if the air temp is higher than ground temp then is the a2w more efficient at this time? Is it only based on the source heat how efficient the pump is? Or is there more to it than that?

Also is a2w very inefficient in sub zero temperatures?

Water John wrote: »

Personnally, I would look at A2W, along with UFH and a timber stove.

Would you just have the timber stove as a space heater and not connected to UFH or for Hot Water? I was going to put one in also. I was just going to leave it for heating room.

Water John

Wouldn't be much into the tech of, why. Liquid to liquid is better thermal transfer, I think.
The best is to use a radiator type exchange located in a nearby stream or lake.

Yes, I would use the stove as a space heater.

Save yourself a tonne of cash bud and forget the money pit of heat pumps. Spend the money on insulation, windows etc and remember your electricity bills will go up especially as it gets colder.

Oil stove definitely the way to go.

top_dog

Deleted User wrote: »

Save yourself a tonne of cash bud and forget the money pit of heat pumps. Spend the money on insulation, windows etc and remember your electricity bills will go up especially as it gets colder.

Oil stove definitely the way to go.

Yea I had looked into getting good insulation in wall but I can't do it cos stone walls have to breathe apparently. Plus the costs of insulation for the walls was by no means cheap and don't want to have dampness and mold problems. I'll be replacing windows and getting good attic insulation and floor insulation.
I have oil at present and it is costing me a fortune.
So at the moment I would be thinking of ground source heat pump with UFH. Also maybe get solar PV panels. Haven't looked at PV panels so don't know the cost. I've heard they coming down in costs though.

Water John

Well, if your digging up the floor anyway, put in UFH. Any heat source can used with them.

If oil is costing you a fortune then you need to insulate as you already know, and unless the house is very airtight and insulation very good the heat pump will also cost you a fortune and be running more than it should be reducing it's already limited life.

Check out the oil stoves, Efel, going for 400-500 on adverts.ie, they were very expensive new and I really love our one and it's very efficient. They can have a boiler or not, have normal oil boiler then for when you're away or for the morning when you need to use the timer. Get a good condenser boiler. They are about 90 odd % efficient, chances are your old boiler is only about 70% efficient saving 20% there already.

Also beware of spending too much money on very expensive triple glazing windows for instance, if your house isn't already very well insulated then chances are more heat will be lost in walls and roof.

And remember, the heat pump needs electricity and that can add a lot of money to your bills especially in cold weather, forget about additional heating nonsense, if the heat pump isn't up to the job it's a waste of money. You may as well install heat storage heaters and run them on night rate electricity ...... sure the heat pump will be more efficient but the purchase and installation costs are a lot, and the running costs won't be too cheap especially if you house isn't up to passive standards.

If and I mean , IF, you save money on a heat pump it will be over many years by which you could be facing having to renew it, if you ask me potential for a bottomless pit. Then it has to be guaranteed to be installed correctly.

I'm also looking at new windows and I'm not keen on Upvc after seeing the condition of mine and many others after as little as 5 years, any efficiency gain is completely lost in a huge amount of these windows and doors from poor construction and bad quality control.

I have a thread started looking for information of quality windows and what type to go for .

vincenzolorenzo

top_dog wrote: »

Sorry just had a query on this as I have read this also. Technically I don't understand how the ground source heat pump is more efficient than a2w? In summer if the air temp is higher than ground temp then is the a2w more efficient at this time? Is it only based on the source heat how efficient the pump is? Or is there more to it than that?

Also is a2w very inefficient in sub zero temperatures?

Air source is more efficient at higher outside temperatures found during summer, but basically no heating load then! GSHP considerably more efficient at sub-zero temperatures but for the most part in Ireland there's not actually that many hours spent at that temperature. Maybe 5% of the year

top_dog

Is there much difference in the running costs between a 10kW heat pump and a 12kW heat pump?

I have provided plans of home to a company for both an a2w and a ground source heat pump. They quoted for a 10kW a2W and 12kW ground. So trying to decide between the two.

a2w: NIBE F2040, 12Kw (230V)
Ground: NIBE F1245, 10Kw

They also quoted for a VVM320 indoor module. I'm not sure why this is required for a2w heat pump but not required for ground?

KCross

vincenzolorenzo wrote: »

Air source is more efficient at higher outside temperatures found during summer, but basically no heating load then! GSHP considerably more efficient at sub-zero temperatures but for the most part in Ireland there's not actually that many hours spent at that temperature. Maybe 5% of the year

Its not just the number of freezing days in the country. Its actually "worse" than that.

The main issue with a2w is that when its cold (single digits) the system freezes and it has to use energy to defrost itself. You'd think that only happens at 0C outside temp but no, it happens at higher temps.

When the a2w HP is running it is bringing liquid in at one temp and sending it back out several degrees below that temp.

So, it might not be freezing outside but the a2w heat pump is freezing.

I don't have figures to quote but the number of days at sub-zero isn't the number of days your system is having to defrost itself and hence being inefficient. It will be more days than that.

On the GSHP side it is almost always bringing its liquid in at 10C+ regardless of outside temp and freezing is never an issue unless installed incorrectly.


That all has to be measured against the different costs between GSHP and A2W, of course.

top_dog wrote: »

Is there much difference in the running costs between a 10kW heat pump and a 12kW heat pump?

I have provided plans of home to a company for both an a2w and a ground source heat pump. They quoted for a 10kW a2W and 12kW ground. So trying to decide between the two.

a2w: NIBE F2040, 12Kw (230V)
Ground: NIBE F1245, 10Kw

They also quoted for a VVM320 indoor module. I'm not sure why this is required for a2w heat pump but not required for ground?

Some A2W system have everything outside including the compressor. Some units have a split system where the fan (and other bits) are outside but everything else is inside.

The GSHP systems are all-in-one systems and are all inside.


On the running costs side of it.... hard to tell. All things being equal the GSHP should always beat the A2W on running costs as they are more efficient. Usually more expensive to install though.

What prices did you get for those 2 systems? It would be an interesting comparison as they are the one manufacturer for the same house.

NOTE: The 10kW and 12kW is the output, not the input. The COP is the figure you actually need to compare.
F2040-12kW has a COP of about 3.6
F1245-10kW has a COP of about 4.8

When they are both running they pull roughly 2kW (less than a kettle) but give different heat outputs for that same energy.

top_dog

Thanks a mill that's great info!

KCross wrote: »

What prices did you get for those 2 systems? It would be an interesting comparison as they are the one manufacturer for the same house.

NOTE: The 10kW and 12kW is the output, not the input. The COP is the figure you actually need to compare.
F2040-12kW has a COP of about 3.6
F1245-10kW has a COP of about 4.8

When they are both running they pull roughly 2kW (less than a kettle) but give different heat outputs for that same energy.

Price
F2040-12kW 7760 €
F1245-10kW 8150 €


Do I need to get the seasonal performance factor value SPF to compare efficiency?


Ground source gives greater heat output for the same energy of 2kW? Is that true to say?

Water John

I presume Cross will be back to answer, but it looks like
12 Kw output divided by 3.6 = 3.3Kw input.
10 Kw output divided by 4.8 = 2.1 Kw input.

Just over a unit of electricity per running hour, of a difference.
You will have other capital costs with the GSHP. Groundworks and housing, mainly.

sheff the ref

This is probably one of the most common sense posts I have read

There is very little talk from people about needing to renew heatpumps. There are a lot of moving parts. Name a mechanical device that can be bought that lasts for 40 years? Yet there is a perception out there that heatpumps will last a lifetime? Granted the real initial outlay is not the overall cost of the heatpump, but the cost differential between that and the alternative heat sources.

Deleted User wrote: »

If oil is costing you a fortune then you need to insulate as you already know, and unless the house is very airtight and insulation very good the heat pump will also cost you a fortune and be running more than it should be reducing it's already limited life.

Check out the oil stoves, Efel, going for 400-500 on adverts.ie, they were very expensive new and I really love our one and it's very efficient. They can have a boiler or not, have normal oil boiler then for when you're away or for the morning when you need to use the timer. Get a good condenser boiler. They are about 90 odd % efficient, chances are your old boiler is only about 70% efficient saving 20% there already.

Also beware of spending too much money on very expensive triple glazing windows for instance, if your house isn't already very well insulated then chances are more heat will be lost in walls and roof.

And remember, the heat pump needs electricity and that can add a lot of money to your bills especially in cold weather, forget about additional heating nonsense, if the heat pump isn't up to the job it's a waste of money. You may as well install heat storage heaters and run them on night rate electricity ...... sure the heat pump will be more efficient but the purchase and installation costs are a lot, and the running costs won't be too cheap especially if you house isn't up to passive standards.

If and I mean , IF, you save money on a heat pump it will be over many years by which you could be facing having to renew it, if you ask me potential for a bottomless pit. Then it has to be guaranteed to be installed correctly.

I'm also looking at new windows and I'm not keen on Upvc after seeing the condition of mine and many others after as little as 5 years, any efficiency gain is completely lost in a huge amount of these windows and doors from poor construction and bad quality control.

I have a thread started looking for information of quality windows and what type to go for .

top_dog

I am looking at the performance specs two different heat pumps. There are a number of different parameters given for rating of the heat pumps performance. Is there anywhere that would explain what each parameter means exactly?

For example could I find where below ratings is explained?

- Rated heat Output
- Seasonal space energy efficiency
- Capacity for space heating Pdh
- COPd
- Degradation coefficient

KCross

top_dog wrote: »

I am looking at the performance specs two different heat pumps. There are a number of different parameters given for rating of the heat pumps performance. Is there anywhere that would explain what each parameter means exactly?

For example could I find where below ratings is explained?

- Rated heat Output
- Seasonal space energy efficiency
- Capacity for space heating Pdh
- COPd
- Degradation coefficient

You'll drive yourself insane trying to compare all those metrics.

I would expect that the most important is the COP(Coefficient of Performance). They are usually expressed under particular scenarios like:

Coefficient of performance (COP) of up to 4.81 at 0/35

That means when running a test to get water from 0C to 35C it can do that with an efficiency of 4.81 (e.g. 1kWh of electricity in gives 4.81kWh energy out).

Read your heart out if you want the specifics...
https://en.wikipedia.org/wiki/Coefficient_of_performance

The main thing is to ensure you look at what conditions the COP figure is given for because some say their COP is , say, 6 but when you look at the fine detail the test was for 7-35 and not 0-35 so that inflates the figure. You need to compare like for like COP figures.

KCross

top_dog wrote: »

Price
F2040-12kW 7760 €
F1245-10kW 8150 €


Ground source gives greater heat output for the same energy of 2kW? Is that true to say?

Yes, thats true to say.

They are very close in price. If you can put in the collector for the GSHP at a reasonably low cost I think it would be the better choice. The GSHP should last longer, require less maintenance and give better ongoing efficiency.

Have they advised you on whether a GSHP would need to be a vertical or horizontal collector based on your ground conditions? A horizontal collector can be done very cheaply. The vertical ones can be expensive and that might rule it out for you but I'd still work the numbers on both before deciding.

top_dog

I have been trying to find out the Seasonal Performance Factor rating as this is what I have been told to compare Heat Pumps. But I don't see them published in the specs by manufacturers. The seasonal performance factor (SPF), which is the ratio of annually delivered useful heat over annually used driving energy. The COP which you have mentioned can be mis-leading.

KCross wrote: »

I would expect that the most important is the COP(Coefficient of Performance). They are usually expressed under particular scenarios like:

Coefficient of performance (COP) of up to 4.81 at 0/35

The main thing is to ensure you look at what conditions the COP figure is given for because some say their COP is , say, 6 but when you look at the fine detail the test was for 7-35 and not 0-35 so that inflates the figure. You need to compare like for like COP figures.

top_dog

They actually do give the Seasonal space heating energy efficiency. Is this the same as SPF?

a2w NIBE F2040 132 %

ground NIBE F1245 147 %

Calahonda52

top_dog wrote: »

I have been trying to find out the Seasonal Performance Factor rating as this is what I have been told to compare Heat Pumps. But I don't see them published in the specs by manufacturers. The seasonal performance factor (SPF), which is the ratio of annually delivered useful heat over annually used driving energy. The COP which you have mentioned can be mis-leading.

That is not correct. and is unfair to KC.
Your definition of SPF is also wrong.

COP and SPF have two different uses and two different math requirements so it depends what the purpose of the calc is
https://www.ofgem.gov.uk/key-term-explained/seasonal-performance-factor-spf
shows where SPF is used and what the industry standard definition of it is.
COP is (energy out)/energy in
where energy out is (energy extracted from the heat source by the refrigerant plus the energy in from the pump)

top_dog

Calahonda52 wrote: »

That is not correct. and is unfair to KC.

I agreed with KC and thanked them for their post. You need to compare COP across different input temperatures as was suggested by KC and which I agreed with. I was making the point using only the COP that manufacturer gives is mis-leading as this is at optimal input temperatures. This is what I concluded from the comment from KC that you shouldn't compare the COP given by the manufacturer and to 'look at the finer detail'.

From KC:
"The main thing is to ensure you look at what conditions the COP figure is given for because some say their COP is , say, 6 but when you look at the fine detail the test was for 7-35 and not 0-35 so that inflates the figure. You need to compare like for like COP figures."

Water John

7-35 tends to be the basic COP standard test.
If you want to judge how models perform in cold weather then you also need to look at 0-35 COP. This is where some makes fell down in the past and gave A2W a poor name.
If you have a hot water facility in the HP you wish to install then, up to 55-60 COP is also important.

Big Dec

From my own experience:
- GSHP generally quoted as 0-35
- ASHP generally quoted as 7-35

This may have changed in newer literature, but was relevant when I was doing my research 3/4 years back.

Condenser

Big Dec wrote: »

From my own experience:
- GSHP generally quoted as 0-35
- ASHP generally quoted as 7-35

This may have changed in newer literature, but was relevant when I was doing my research 3/4 years back.

If you want to compare these two technologies at an equivalent level then you need to use A2/W35 and B0/35 otherwise you are not comparing like with like. This was always the european standard until recently when the big a2w manufacturers began to bend the figures to make their systems look better using the argument that the average air temp in this part of the word was 7c. However using that logic ground source should be quoting B5/W35 as this is more representative of the actual year round temp in a collector, better designed systems being even higher. I have never seen a gshp with a brine temp of 0C.

mossie

I have a NIBE Fighter 1240, 8 / 9 years old, never had a problem up to now.I had a power cut on Friday, since then the system hasn't returned to normal operation. The screen shows "NIBE AB Fighter 12XX 1.18" and hasn't progressed past this. The green light is on and the icons at the top of the screen come and go. Any ideas what the problem could be?

rolion

Hi,

To all of the HP owners...I understood that pump is fine for heating the house at around 45 degrees value, plus or minus.
My question is...what do you use to heat the domestic hot water ,that will need to be at around 60-70 degrees at the top of the cylinder, with maybe 30-40 at the bottom of it !? And let's say a size of 300 litres cylinder...

Thanks.

sheff the ref

Generally an the immersion will be timed to cut in to top up the temperature. The hard work is already done heating to 45 degrees

rolion wrote: »

Hi,

To all of the HP owners...I understood that pump is fine for heating the house at around 45 degrees value, plus or minus.
My question is...what do you use to heat the domestic hot water ,that will need to be at around 60-70 degrees at the top of the cylinder, with maybe 30-40 at the bottom of it !? And let's say a size of 300 litres cylinder...

Thanks.

mike_2009

You can get CO2 ASHP's that works at highers temps (60oC) but these are rarer.

GraceKav

Looking for opinions on the below if anyone has any insight. Have done as much online digging as I can so far and will be sitting down to ask our architect this week but always good to get some different perspectives too.

Going for planning in the next few weeks so finalising house plans. Planning a 211m2 bungalow with UFH/ASHP/MVHR. Our architect is advising us to put the ASHP in the shed which will be approx 16-25m from the house. I need to check with them if this is a monoblock or split system. The shed was originally meant to be much nearer the house but was pushed back based on our request. I have an option to put an extra 70cmx200cm onto the laundry room (pulling from the sitting room which doesn't need the space) which would, based on my reading, give enough space to have a split system attached to the house rather than the shed. Just wondering what peoples' views are on this set up vs the original setup?

Some of the factors I've come up with based on my own research are:
- If have it in the shed, would need to insulate the piping into the house to prevent heat loss (have seen estimates of approx €40p/m on another thread)
- If we put it onto the house, it will be only 3-6m from the bedrooms and I believe some people have had issues with noise
- It would also be only 1-2m from the back door and I've seen comments from another reader that this can catch you with a blast of air every time you enter/exit
- A friend of ours has their unit in the utility and she raves about how quickly the clothes dry due to the piping etc - not sure if this would be the case for everyone as I didn't think the unit gave off that much ambient heat itself but definitely a plus if true
- Would prefer the unit indoors so that if we have to adjust we don't have to walk all the way outside
- Would worry that if the temp drops below freezing, we would be at more risk of pipes freezing etc if we had the unit in the shed particularly if we were away for a week or two and turned the unit off

Would welcome any feedback on the above as well as any estimated cost variances between the two options as well as maintenance issues. Any feedback on monoblock vs split would also be appreciated as I can't seem to find much opinion between the two options online except for the below Boards thread which is 5 years old and therefore may not be accurate today.

http://www.boards.ie/vbulletin/showthread.php?t=2056584700

Thanks in advance for the help.

antoinolachtnai

Why does the architect want to do this? He wants to put it in the shed? Or beside the shed? If the former, is this shed going to be sealed?

The house won't even be 16-25 meters in length/width? It sounds like a very long run. The furthest heating element will be about 120 feet from the heat source whereas if it were in or alongside the building, it would only be 60 feet away. I have no experience of such a thing, but it doesn't sound like a great idea to me.

What analysis has the architect done to justify his recommendation? Has the manufacturer of the heat pump said that this is ok? It is really up to him to justify this recommendation.

Water John

One point, it is certainly, not a good idea to dry clothes in a modern, well sealed, insulated house, either for the house or the residents.
Suggest a HP condenser dryer. Very good, works at lower temp and leaves clothes soft.
Sorry to be off topic.

GraceKav

antoinolachtnai wrote: »

Why does the architect want to do this? He wants to put it in the shed? Or beside the shed? If the former, is this shed going to be sealed?

The house won't even be 16-25 meters in size? It sounds like a very long run. The furthest heating element will be about 120 feet from the heat source whereas if it were in or alongside the building, it would only be 60 feet away. I have no experience of such a thing, but it doesn't sound like a great idea to me.

What analysis has the architect done to justify his recommendation? Has the manufacturer of the heat pump said that this is ok? It is really up to him to justify this recommendation.

We're sitting down to chat through with him this week as I think there may be cross wired somewhere. He calls it a garage and I call it a shed. In my mind, it will not be sealed as I don't want to be pumping a ton of money into a shed that I only want up to scratch for holding bins and gardening equipment. In his defence, the garage/shed had been right beside the house but we didn't like the approach and so pushed it further back but based on that change, I now don't think (whatever about before the move) that it makes sense anymore to have the pump in the shed when we have the space for it in the house.

As we're only going for planning permission shortly, we haven't gotten to the stage where the HP has been spec'd out or where we've spoken with suppliers yet.

Water John wrote: »

One point, it is certainly, not a good idea to dry clothes in a modern, well sealed, insulated house, either for the house or the residents.
Suggest a HP condenser dryer. Very good, works at lower temp and leaves clothes soft.
Sorry to be off topic.

Why is this? I prefer not to use a dryer and in fact we're having the separate laundry room as we'll be having dogs and we want a place that we can leave the clothes dryer out for airing. We'll be having MVHR and I thought so long as you spoke with the supplier and made sure that any rooms where there may be extra condensation e.g. bathrooms, laundry etc, were called out early in the process so that adequate ventilation could go in, it should be fine?

froshtyv

There is definitely no problems positioning a split heat pump outdoor unit away from the house, how far away will depend on the size and make of the unit.
Some will have a max distance of 25m, some will be more.
Forget about putting the indoor unit of the heat pump in an unheated space such as you garage, keep it in your house.
Simple reasons being heat and transfer losses by the time your hot water gets to your house.
A heat pump is at its worst efficiency when it is in hot water production so you don't want to make this worse by positioning your indoor unit outside the building envelope.
A good few manufactures have an integrated indoor unit which means your hot water cylinder and circulating pump are located all inside one unit roughly 1750mm high, 600mm in width and 730mm deep, so they will fit in most utilities.
If you have seen the room to improve episode with Dessie Dolan in Moate, they had an integrated unit fitted in their utility and that was the fussiest utility that Ireland has ever seen (",) (see attached image)


Advantages of split over a monobloc are;
Flexibility of being able to position the outdoor unit away from the house without incurring heat and transfer losses like found in a monobloc.
I have seen monoblocs loose up to 7c by the time the water is transferred inside to the house when they are mounted away from the house.
Refrigerant gas in the split versus water in a monobloc.

The split system will have no water located outside so less prone to freezing compared to a monobloc.

In relation to drying clothes, the main thing you need to ensure is that the room that you are planning to use is ventilated, but i am sure this will be the case if you are planning to instal MHRV.

GraceKav wrote: »

Looking for opinions on the below if anyone has any insight. Have done as much online digging as I can so far and will be sitting down to ask our architect this week but always good to get some different perspectives too.

Going for planning in the next few weeks so finalising house plans. Planning a 211m2 bungalow with UFH/ASHP/MVHR. Our architect is advising us to put the ASHP in the shed which will be approx 16-25m from the house. I need to check with them if this is a monoblock or split system. The shed was originally meant to be much nearer the house but was pushed back based on our request. I have an option to put an extra 70cmx200cm onto the laundry room (pulling from the sitting room which doesn't need the space) which would, based on my reading, give enough space to have a split system attached to the house rather than the shed. Just wondering what peoples' views are on this set up vs the original setup?

Some of the factors I've come up with based on my own research are:
- If have it in the shed, would need to insulate the piping into the house to prevent heat loss (have seen estimates of approx €40p/m on another thread)
- If we put it onto the house, it will be only 3-6m from the bedrooms and I believe some people have had issues with noise
- It would also be only 1-2m from the back door and I've seen comments from another reader that this can catch you with a blast of air every time you enter/exit
- A friend of ours has their unit in the utility and she raves about how quickly the clothes dry due to the piping etc - not sure if this would be the case for everyone as I didn't think the unit gave off that much ambient heat itself but definitely a plus if true
- Would prefer the unit indoors so that if we have to adjust we don't have to walk all the way outside
- Would worry that if the temp drops below freezing, we would be at more risk of pipes freezing etc if we had the unit in the shed particularly if we were away for a week or two and turned the unit off

Would welcome any feedback on the above as well as any estimated cost variances between the two options as well as maintenance issues. Any feedback on monoblock vs split would also be appreciated as I can't seem to find much opinion between the two options online except for the below Boards thread which is 5 years old and therefore may not be accurate today.

http://www.boards.ie/vbulletin/showthread.php?t=2056584700

Thanks in advance for the help.

Condenser

froshtyv wrote: »

There is definitely no problems positioning a split heat pump outdoor unit away from the house, how far away will depend on the size and make of the unit.
Some will have a max distance of 25m, some will be more.
Forget about putting the indoor unit of the heat pump in an unheated space such as you garage, keep it in your house.
Simple reasons being heat and transfer losses by the time your hot water gets to your house.
A heat pump is at its worst efficiency when it is in hot water production so you don't want to make this worse by positioning your indoor unit outside the building envelope.
A good few manufactures have an integrated indoor unit which means your hot water cylinder and circulating pump are located all inside one unit roughly 1750mm high, 600mm in width and 730mm deep, so they will fit in most utilities.
If you have seen the room to improve episode with Dessie Dolan in Moate, they had an integrated unit fitted in their utility and that was the fussiest utility that Ireland has ever seen (",) (see attached image)


Advantages of split over a monobloc are;
Flexibility of being able to position the outdoor unit away from the house without incurring heat and transfer losses like found in a monobloc.
I have seen monoblocs loose up to 7c by the time the water is transferred inside to the house when they are mounted away from the house.
Refrigerant gas in the split versus water in a monobloc.

The split system will have no water located outside so less prone to freezing compared to a monobloc.

In relation to drying clothes, the main thing you need to ensure is that the room that you are planning to use is ventilated, but i am sure this will be the case if you are planning to instal MHRV.

The bolded above is completely incorrect. There are massive heat losses associated with most split units situated away from a house. Most split units have the compressor in the outdoor unit so this is where your heat is generated. The discharge gas that leaves the compressor is usually 55C+ on heating and can be over 80C on hot water. Given that these pipes are generally only insulated in armaflex and thrown in a sewer pipe until they reach the house then the heat losses are massive. The temperature also means the insulation degrades over time and you end up with no insulation. To top it off the sewer pipe is rarely sealed and usually fills with water so half the time 50% of your energy is heating the ground. Unless its a split heat pump with compressor inside and only the evaporator and fan outside this is most definitely the case.


Also on the original question, under no circumstances should you put an air source heat pump in your shed. It will short cycle the air available continuously blowing out cold air and sucking it back in meaning your performance drops off a cliff. I once visited a shed where the internal temperature was -7 when it was 10C outside where this exact set up was done.


Don't rely on your architect to give you the full info either as he's only passing on info he received from salesmen that have visited him. You really shouldn't rule out a GSHP as its superior in every way from running costs, to lifetime, to noise. That fact has been lost to the large advertising budgets of the big ASHP players.

GraceKav

Thanks for the replies guys. You've confirmed what I was thinking. Going to defo free up space to move the system inside the house.

Condenser wrote: »

Don't rely on your architect to give you the full info either as he's only passing on info he received from salesmen that have visited him. You really shouldn't rule out a GSHP as its superior in every way from running costs, to lifetime, to noise. That fact has been lost to the large advertising budgets of the big ASHP players.

Also leaning back towards an energy consultant for the build. Seems sensible given the amount of conflicting advice out there and how hard this stuff is for a layperson to understand.

Re the GSHP, I've gone away from this for several reasons:
- don't think we can afford the capital outlay which makes the decision quite easy. Inital capital outlay on the ASHP is much less from everything I've heard.
-want to plant trees throughout the site and know there can be issues with roots with the GSHP with advice being, don't plant anything with large roots anywhere near them.
- I'm sure people will argue this last one with me but if something goes wrong, the ASHP feels much more accessible for repairs/maintenance/replacing parts etc. The thought of getting a burst pipe or something with the GSHP scares me quite a bit even though logically I know the likelihood is low.

Condenser

GraceKav wrote: »

Thanks for the replies guys. You've confirmed what I was thinking. Going to defo free up space to move the system inside the house.



Also leaning back towards an energy consultant for the build. Seems sensible given the amount of conflicting advice out there and how hard this stuff is for a layperson to understand.

Re the GSHP, I've gone away from this for several reasons:
- don't think we can afford the capital outlay which makes the decision quite easy. Inital capital outlay on the ASHP is much less from everything I've heard.
-want to plant trees throughout the site and know there can be issues with roots with the GSHP with advice being, don't plant anything with large roots anywhere near them.
- I'm sure people will argue this last one with me but if something goes wrong, the ASHP feels much more accessible for repairs/maintenance/replacing parts etc. The thought of getting a burst pipe or something with the GSHP scares me quite a bit even though logically I know the likelihood is low.

I think if you really sit down and weed out the answers you get from suppliers its not that difficult to sort the genuine info from the bs. Too many people get clouded by budget and end up wanting to believe the item that fits their budget is going to be fine and they miss the detail in what they're told. Budget of course has a role but you should always approach it as if it doesnt matter. Listen to all opinions even if you think its outside what you can afford. You'll quickly figure out the realities once you apply common sense and also once you hear common sense from a supplier.

A decent supplier should give you information not a sales pitch. Anyone that is willing to match every requirement you think you want is not worth listening too. This is especially true of heat pumps where the supplier should guide you on best practice. If they bend to your every whim they only want a sale and don't care about the result. You can easily test this.

Regarding the Gshp you'll find its not very much more than an ashp (really good ashp's are actually more expensive.), will run for about half the cost, will last at least twice as long, have far less parts failures, be very consistent regardless of the weather conditions.

Roots are only an issue with deep rooting trees. A borehole can be used if space is limited and I've never seen a burst pipe other than one where someone stuck a digger bucket through it and theyre easy to find . Far more likely to see damage to an ashp due to storms, kids putting sticks in the fan blades, reversing a car into it, coil failure due to metal fatigue from defrosting, corrosion and other issues.

Calahonda52

GraceKav wrote: »

....... Planning a 211m2 bungalow with UFH/ASHP/MVHR. ......

This just looks all wrong: you are shelling out serious mula, may 400k plus, on a build that is inherently flawed from an energy design perspective because your arch does not understand the way a MHVR works..
Loose the UFH and the HP and put the money towards getting close to Passiv Haus Standard, which can be heated for next to nothing with the MHVR and maybe a small wood pellet stove, not multi fuel if you want the PH cert, not needed, see below.
Use PV to get past the Renewables requirement.

MHVR extracts from the wet rooms and supplies to the rooms that need heat, which are already going to be hot with the UFH.......

Get a decent MHVR unit, c/w a cooling fan coil to take out the humidity in those humid summer days when the summer bypass is on, make sure yours has one.
Consider getting another elec heated fan coil unit to boost the supply from the MHVR on those cooler days.

The above maybe breach the strict PH elec energy footprint requirements but I did not say get the PH cert, just adopt the methodology for A/T and Insulation.

sheff the ref

There is a very good article on heatpumps here

http://www.irishexaminer.com/lifestyle/homeandinteriors/homehelp/upgrading-your-home-heating-system-376263.html

MENACE2010

GraceKav wrote: »

Looking for opinions on the below if anyone has any insight. Have done as much online digging as I can so far and will be sitting down to ask our architect this week but always good to get some different perspectives too.

Going for planning in the next few weeks so finalising house plans. Planning a 211m2 bungalow with UFH/ASHP/MVHR. Our architect is advising us to put the ASHP in the shed which will be approx 16-25m from the house. I need to check with them if this is a monoblock or split system. The shed was originally meant to be much nearer the house but was pushed back based on our request. I have an option to put an extra 70cmx200cm onto the laundry room (pulling from the sitting room which doesn't need the space) which would, based on my reading, give enough space to have a split system attached to the house rather than the shed. Just wondering what peoples' views are on this set up vs the original setup?



Some of the factors I've come up with based on my own research are:
- If have it in the shed, would need to insulate the piping into the house to prevent heat loss (have seen estimates of approx €40p/m on another thread)
- If we put it onto the house, it will be only 3-6m from the bedrooms and I believe some people have had issues with noise
- It would also be only 1-2m from the back door and I've seen comments from another reader that this can catch you with a blast of air every time you enter/exit
- A friend of ours has their unit in the utility and she raves about how quickly the clothes dry due to the piping etc - not sure if this would be the case for everyone as I didn't think the unit gave off that much ambient heat itself but definitely a plus if true
- Would prefer the unit indoors so that if we have to adjust we don't have to walk all the way outside
- Would worry that if the temp drops below freezing, we would be at more risk of pipes freezing etc if we had the unit in the shed particularly if we were away for a week or two and turned the unit off

Would welcome any feedback on the above as well as any estimated cost variances between the two options as well as maintenance issues. Any feedback on monoblock vs split would also be appreciated as I can't seem to find much opinion between the two options online except for the below Boards thread which is 5 years old and therefore may not be accurate today.

http://www.boards.ie/vbulletin/showthread.php?t=2056584700

Thanks in advance for the help.

Hi ,
we have a "plant room" at the side of the house where we have housed the ventialation , Heatpump, watercylinder and all other stuff that deals with the house mechanicals as i had to point out to the architect as well that we ran out of space in the copious designed utility room ..the plant room is about 4 sqm with a window in it and drain pipe in the floor for those situations that causes water overflow .. ( it happened , expansion tank failed water seeped in the drain instead of the room) .
about the location bear in mind the closer you keep the heat source to the house less loss it really that simple ..
. We have an Air Source heat pump , mounted on the concrete footpath around the house not on the wall of the house to mitigate vibration . The supplier of the heat pump recommends to use flexible hose to the heat exchanger but our plumber mounted it with fixed piping .. the noise is not that awful ( we have triple glazing and the pump is not around the window of any bedroom) but it will increase when its colder !! bear that in mind .. the colder it gets outside the harder the compressor will work -= more noise ..

if possible insulate the living daylight out of the house.. that is all i can advise you ( triple glazing, insulated plasterboard etc ).. it will keep the bills down, go for spread payment with your electricity provider so you have a fixed fee through the year. ( we are currently paying 130 euro a month it is reviewed every 6 months, its easier to manage)

good luck with your build..

hero25

GraceKav wrote: »

Looking for opinions on the below if anyone has any insight. Have done as much online digging as I can so far and will be sitting down to ask our architect this week but always good to get some different perspectives too.

Going for planning in the next few weeks so finalising house plans. Planning a 211m2 bungalow with UFH/ASHP/MVHR. Our architect is advising us to put the ASHP in the shed which will be approx 16-25m from the house. I need to check with them if this is a monoblock or split system. The shed was originally meant to be much nearer the house but was pushed back based on our request. I have an option to put an extra 70cmx200cm onto the laundry room (pulling from the sitting room which doesn't need the space) which would, based on my reading, give enough space to have a split system attached to the house rather than the shed. Just wondering what peoples' views are on this set up vs the original setup?

Some of the factors I've come up with based on my own research are:
- If have it in the shed, would need to insulate the piping into the house to prevent heat loss (have seen estimates of approx €40p/m on another thread)
- If we put it onto the house, it will be only 3-6m from the bedrooms and I believe some people have had issues with noise
- It would also be only 1-2m from the back door and I've seen comments from another reader that this can catch you with a blast of air every time you enter/exit
- A friend of ours has their unit in the utility and she raves about how quickly the clothes dry due to the piping etc - not sure if this would be the case for everyone as I didn't think the unit gave off that much ambient heat itself but definitely a plus if true
- Would prefer the unit indoors so that if we have to adjust we don't have to walk all the way outside
- Would worry that if the temp drops below freezing, we would be at more risk of pipes freezing etc if we had the unit in the shed particularly if we were away for a week or two and turned the unit off

Would welcome any feedback on the above as well as any estimated cost variances between the two options as well as maintenance issues. Any feedback on monoblock vs split would also be appreciated as I can't seem to find much opinion between the two options online except for the below Boards thread which is 5 years old and therefore may not be accurate today.

http://www.boards.ie/vbulletin/showthread.php?t=2056584700

Thanks in advance for the help.

we recently completed a 3200 sq ft house, so if i can help by giving my experience....
we have A2W with UFH on both first and 2nd floor.

I believe the Heatpump has to be outside - getting the air!
We placed our heatpump ~20m away from the house, for similar reasons to yourself. While the most efficient place is seemingly close to the water tank and control unit (makes sense)... we didn't like the aesthetics of outside the back door, it does make noise and would have been underneath/close to a bedroom.
Your costs for that insulated pipe are right, ~40euro/m. So we may be losing some heat and money in the 20m run to the house, but in our opinion, it's worth it. Our plumber wouldn't place the Heatpump any further than ~20m from the water tank/control unit- too inefficient.
He also wouldn't place the internal water tank and control unit in the garage (we did ask) - as he explained, any time hot water was needed in the house (for showers, UFH heating etc) - it would take too long to get to the house and if we were to do that, we would have needed another buffer tank in the house. Someone above posted similar comments. So we placed the tank and the internal unit indoors in utility room. It all fits in <1metre wide, tall press.

you're right re it doesn't generate huge heat itself, but the manifold (and washing machine and/or tumble dryer) does generate some heat - hence the utility room does end up being warm and is good for drying clothes.

hope that helps;)

caddy16

Currently researching for a new build - for people who have a heat pump with UFH how has it worked over the last week or 2.
As in I've had to turn on oil central heating in current house for an hour in the mornings and evenings due to the drop in temp - is your heating constantly on at a set temp?

Just trying to figure out the practicalities of a system I've no experience of.

KCross

caddy16 wrote: »

Currently researching for a new build - for people who have a heat pump with UFH how has it worked over the last week or 2.
As in I've had to turn on oil central heating in current house for an hour in the mornings and evenings due to the drop in temp - is your heating constantly on at a set temp?

Just trying to figure out the practicalities of a system I've no experience of.

Mine (Nibe Geothermal) usually comes on around the 2nd or 3rd week of Sept. It went off again for a few days earlier in the week but is on again now.

It decides based on the average temperature over a 24hr period. If that average drops below a set value it comes on. The idea is that the house remains at the same temp, which it generally does.

In another few weeks when the average temp drops further it will stay on 24/7. It doesn't work like a traditional oil system where you give it a blast for an hour.

caddy16

KCross wrote: »

Mine (Nibe Geothermal) usually comes on around the 2nd or 3rd week of Sept. It went off again for a few days earlier in the week but is on again now.

It decides based on the average temperature over a 24hr period. If that average drops below a set value it comes on. The idea is that the house remains at the same temp, which it generally does.

In another few weeks when the average temp drops further it will stay on 24/7. It doesn't work like a traditional oil system where you give it a blast for an hour.

Thanks Kcross, appreciate the response. So is your until "on" all year round but only kicks in when required on avg temps as you mentioned above?

KCross

caddy16 wrote: »

Thanks Kcross, appreciate the response. So is your until "on" all year round but only kicks in when required on avg temps as you mentioned above?

Yes, its a fully automated system. You don't turn it on/off like oil heating.

The unit is actually powered on 365 days of the year because it also heats the water each day but it automatically turns off the space heating once the avg temp drops below the set value so it turns off the circulating pumps relating to the space heating (i.e. the UFH pump) and continues to heat hot water as required each day.

caddy16

KCross wrote: »

Yes, its a fully automated system. You don't turn it on/off like oil heating.

The unit is actually powered on 365 days of the year because it also heats the water each day but it automatically turns off the space heating once the avg temp drops below the set value so it turns off the circulating pumps relating to the space heating (i.e. the UFH pump) and continues to heat hot water as required each day.

Makes sense, thanks. Do you find the system reacts adequately at this time of year when temps fluctuate or have you an alternative source such as a stove?

Sorry for all the questions!

KCross

caddy16 wrote: »

Makes sense, thanks. Do you find the system reacts adequately at this time of year when temps fluctuate or have you an alternative source such as a stove?

Sorry for all the questions!

It reacts fine. It uses what they call "weather compensating control". It has an outdoor stat so it knows the outdoor temp and will come on in advance to ensure that the house temp is maintained.

With UFH it takes several hours for the heat to build up and be released so there is no point coming on when the house temp has dropped, as thats too late. It comes on when the outside temp drops which gives it the few hours head start to cover the heat loss that the house will suffer in the hours ahead that day. It works.

My house is at 21C 24/7. You can adjust that up/down to suit your needs.

Note, my system is geothermal. There is also air-to-water heat pump systems.
The balancing act is the once off higher capital cost of geothermal vs the higher running and maintenance costs of air-to-water.

I have a kWh meter on my heat pump and it cost exactly €696 in electricity to cover all heating and hot water from Sep 16-Sep 17 in a 350m2 house.