Air source heat pump

murphaph

To be honest your builder won't be paying the heating costs and probably doesn't really care what you end up with. This is an area for a specialist who can predict the heating demand for the building/rooms and advise you independently of the guy who you're paying to build it (who may well and probably does have his own motives for recommending x, y or z).

"Free" advice on here will possibly cost you more in the long run as nobody has access to your plans. It's a decision that you need to get as right as you can or you may end up paying dearly for it.

Edit: Is there a reason why UFH has been ruled out?

dc14

I'd be happy to pay for advice on this as I really want to get it right, but can't find an independent 'Heating advisor'. I obviously don't want to go on the word of the suppliers as they have a vested interested and they are all telling me different things. I tried calling the SEAI to see if they could recommend an advisor, but they couldn't. If you know of anyone, I'd be grateful if you could pm me. Thx!

froshtyv

dc14 wrote: »

Yeah, that's why the builder is saying to go with Alu rads, they are lower temp than normal. Has anyone got an idea about how much this would affect the COP?

Also, which is the best brand -snip-

The idea of using aluminium radiators is that they can be sized to work with a low flow temperature which is what a heat pump produces.

It would depend on what delt T the rads are sized at that would then tell you what efficiency your heat pump would be.

The bigger the rad the lower the flow temperature can be to meet the heat demand of the room, the better efficiency from your heat pump.

At minimum i would have UFH on a ground floor of a house.

Most peoples kitchens have minimum wall space for rads, let alone enough wall space to mount an adequate sized aluminium radiator.

Steel rads are not suited to a low temperature heating system

bartbu

Hi guys.
Following this thread with interest. Thinking of going with atw heat pump. Solid fuel stove with back boiler. Solar panels...All going to buffer tank. Underfloor downstairs. Alu rads upstairs. 3000 Sq foot .....how does this sound. Brain fried...
Is the -snip- pump a no go ...They can integrate the stove...any help much appreciated

afinador

Hi Bartbu
That's a whole lot of heating going on!
Guessing you're going for the stove coz you like the look of it, but solar panels and heat pump?
We did a seriously deep retrofit and just the atw HP, no underfloor, and 2 large standard rads downstairs...HP copes with all the hot water and space heat requirement
Think your better off getting a seriously good ACH and insulating the beejayzuz out of it. Then stick in HRV and you'll wonder why you bothered with the stove!

BarneyMc

I was also going to integrate the stove & back boiler but have given up on that idea as it's just not practical with UFH and would cost considerable money. I'll just be going with a standalone stove plus air to water heat pump with UFH.

DeeJunFan

Thats the thing if you build the house well insulated and good levels of airtightness your not going to need that much heat.

Sister has a house built 5 years ago with good levels of insulation (not as good as people would go with now) and good level of airtightness again not what people would settle for now.

She only ever uses the stove if the ASHP is getting serviced or has a problem, which is 3 days in the last 5 years. even then when she puts the stove on the room heats up so quick she has to just let it go out again.

I'm thinking of just going for a (shudder to think it) LED wall mounted fire with a 2kw fan heater. There are some nice ones and they are totally air tight as the chimney breast is just a block wall and there is no air coming in or going out.

bartbu

A lot going on alright but have access my own solid fuel supply. Am told air to water on its own will not pass regs for house my size. 3400 Sq feet. Hope to run on solid fuel for most of less severe months with solar for hot water. Am told I can turn pump off during get these warmer months. Will have mrhv also. . Am I mad!!

BarneyMc

I have my own solid fuel supply also but can still burn it in the standalone stove - this still contributes to the heating of the house. Also, I would have thought the stove would contribute to passing the regs whether or not it was connected to your central heating system? Furthermore if you're installing solar then that's yet another plus for compliance? Are you really sure you need all this to comply?

bartbu

Cheers barney. Does it cost much to connect stove to back boiler. Open to your idea also. Like the solar panel idea as we will have hot water this time of year without drawing from heat pump and just put pump on standby. . What you think

BarneyMc

I got a quote of €1,500 for the exchange unit to do this bartbu. This would not include the tank upgrade or extra plumbing and electrical costs. I spoke to a few experts in this area and they advised me to ditch the integrated stove idea.

I'm not an expert in this area but from what I've picked up it might be more economical to run your heat pump in the summer months for hot water rather than solar panels - most HPs should be able to differentiate between heating and hot water needs. Personally I'll hold off with the solar panels and just rely on the HP which should be efficient in the summer (especially these days!) anyway. In the future I might invest in PV panels and use them to power the HP and any other electrical devices it can power. This might be a more productive investment than solar panels especially if you have a mortgage (you'll be paying interest on this extra mortgage to buy the panels).

Anyway you'll need some professional advice on what you need to meet the regs and then figure out what's the best way to meet them. As I say I'm not an expert here and stand corrected on everything I've just said!!!

galwaytt

BarneyMc wrote: »

I got a quote of €1,500 for the exchange unit to do this bartbu. This would not include the tank upgrade or extra plumbing and electrical costs. I spoke to a few experts in this area and they advised me to ditch the integrated stove idea.

I'm not an expert in this area but from what I've picked up it might be more economical to run your heat pump in the summer months for hot water rather than solar panels - most HPs should be able to differentiate between heating and hot water needs. Personally I'll hold off with the solar panels and just rely on the HP which should be efficient in the summer (especially these days!) anyway. In the future I might invest in PV panels and use them to power the HP and any other electrical devices it can power. This might be a more productive investment than solar panels especially if you have a mortgage (you'll be paying interest on this extra mortgage to buy the panels).

Anyway you'll need some professional advice on what you need to meet the regs and then figure out what's the best way to meet them. As I say I'm not an expert here and stand corrected on everything I've just said!!!

Not sure how you figure solar more expensive than panels in summertime. My 1000L buffer tank is full of DHW with zero cost. How do you improve on that ???

BarneyMc

galwaytt wrote: »

Not sure how you figure solar more expensive than panels in summertime. My 1000L buffer tank is full of DHW with zero cost. How do you improve on that ???

I didn't make any such claim. This is what I said: "...This might be a more productive investment than solar panels especially if you have a mortgage (you'll be paying interest on this extra mortgage to buy the panels)."

Both will produce "zero cost" hot water in Summertime but in different ways. PV has added benefit of powering any electrical device so you might end up with "free" hot water, tv, washing machines, etc.

I would be careful using the words "zero cost". Panels/PV cells have to be bought and installed and you'll be paying interest on this in the form of a mortgage over x years. This equipment will not last forever and so it's an investment over the lifetime of the equipment.

Again, I'm no expert in this area but not afraid to look at the real cost of "free" stuff.

froshtyv

bartbu wrote: »

Hi guys.
Following this thread with interest. Thinking of going with atw heat pump. Solid fuel stove with back boiler. Solar panels...All going to buffer tank. Underfloor downstairs. Alu rads upstairs. 3000 Sq foot .....how does this sound. Brain fried...
Is the Samsung joule heat pump a no go ...They can integrate the stove...any help much appreciated

Its considerably more expensive to integrate all these heat systems together correctly mechanically and electrically.
It would be better to have the stoves separate from the heating system.
You would need to get in contact with a heating specialist to see how it should be done correctly.

bartbu wrote: »

A lot going on alright but have access my own solid fuel supply. Am told air to water on its own will not pass regs for house my size. 3400 Sq feet. Hope to run on solid fuel for most of less severe months with solar for hot water. Am told I can turn pump off during get these warmer months. Will have mrhv also. . Am I mad!!

The size of your house will not determine if you will pass or fail on the building regs, there are multiple factors which make up the overall figures.

bartbu

froshtyv wrote: »

Its considerably more expensive to integrate all these heat systems together correctly mechanically and electrically.
It would be better to have the stoves separate from the heating system.
You would need to get in contact with a heating specialist to see how it should be done correctly.





The size of your house will not determine if you will pass or fail on the building regs, there are multiple factors which make up the overall figures.

Was talking to ber assessor. Says air to water. Solar panels. Mrhv. And all the air tightness and high spec insulation. Plus dry solid fuel stove. . Will not meet part l compliance unless I put underfloor upstairs and down . Want carpets upstairs so this not an option. . Does this make sense. He might also have vested interest in providing systems. . Any ideas anyone?

dc14

Wow! He says it won't pass unless you have all that? I better talk to my builder again.

BarneyMc

I find that hard to believe also but again don't know enough to know. Are you really sure you want carpets upstairs by the way?

froshtyv

bartbu wrote: »

Was talking to ber assessor. Says air to water. Solar panels. Mrhv. And all the air tightness and high spec insulation. Plus dry solid fuel stove. . Will not meet part l compliance unless I put underfloor upstairs and down . Want carpets upstairs so this not an option. . Does this make sense. He might also have vested interest in providing systems. . Any ideas anyone?

Im assuming you are going with Alu rads for the first floor so?

By doing this you will reduce the EAF of the heat pump for space heating in the BER file.

Every house will differ from an energy rating even if the houses were the same size.

This comes down to budget, the lower the U value of a product generally the more expensive.


What I find a lot is that a BER assessor will do plenty of work with regards to the building envelope and get all the U-values to meet compliance.

But then they have to enter a non practicable heat pump with a high SPF from the harp database to get it over the line for rest of the compliance.

The heat pump is usually the wrong size for the house, and sometimes i see a water-to-water heat pump entered.

Where as from the start the heat pump should be decided upon and the rest of the house based around this.

This leads to money being better spent on insulation rather than lower grade insulation and a more expensive heat pump.

bartbu

froshtyv wrote: »

Im assuming you are going with Alu rads for the first floor so?

By doing this you will reduce the EAF of the heat pump for space heating in the BER file.

Every house will differ from an energy rating even if the houses were the same size.

This comes down to budget, the lower the U value of a product generally the more expensive.


What I find a lot is that a BER assessor will do plenty of work with regards to the building envelope and get all the U-values to meet compliance.

But then they have to enter a non practicable heat pump with a high SPF from the harp database to get it over the line for rest of the compliance.

The heat pump is usually the wrong size for the house, and sometimes i see a water-to-water heat pump entered.

Where as from the start the heat pump should be decided upon and the rest of the house based around this.

This leads to money being better spent on insulation rather than lower grade insulation and a more expensive heat pump.

Cheers froshtyv. .
Makes sense. My wife wants carpet in bedroom but might put underfloor everywhere else both up and downstairs.
Anyone have recommendations on best brands of heat pumps available or any reputable companies in Galway to provide pump and underfloor.
Thanks for help.

howman

having made my mind up on A2W unit

I am now firmly back on the fence

the advice I received earlier in this thread is really starting to make sense

with stoves in my living areas, ufh upstairs and down, very high spec insulation levels, high spec windows (double glazed, site is south facing), just looking at goin the lpg tank route and a decent boiler, which supplying low temp to my ufh, should be very efficient...

just wondering if I will need to add solar to get me passed the regs..

MHRV - have no faith in this, fail to see how this has any level of efficiency therefore staying clear

anyone have any advice for me

hexosan

howman wrote: »

.

MHRV - have no faith in this, fail to see how this has any level of efficiency therefore staying clear

anyone have any advice for me

Simple question how else do you plan on ventilating the house ??

howman

hexosan wrote: »

Simple question how else do you plan on ventilating the house ??

window vents

hexosan

So your willing to pay to keep your heating on while all that heat pisses out the windows with none of it recovered. ??

I think you need to research exactly what MVHR actually is.

howman

hexosan wrote: »

So your willing to pay to keep your heating on while all that heat pisses out the windows with none of it recovered. ??

well IMHO, you will probably suffer more losses via an over active vent system than trickle vents

what average efficiency are we looking at based on average room temp and normal Irish weather?

hexosan

What Airtightness target and you aiming for

howman

hexosan wrote: »

What Airtightness target and you aiming for

2.5 to 3 ac/hr

MicktheMan

howman wrote: »

MHRV - have no faith in this, fail to see how this has any level of efficiency therefore staying clear

anyone have any advice for me

And this lack of faith comes from what / where exactly?

howman wrote: »

window vents

Don't work in low permeability houses

howman wrote: »

well IMHO, you will probably suffer more losses via an over active vent system than trickle vents

what average efficiency are we looking at based on average room temp and normal Irish weather?

In this day and age of highly insulated and airtight buildings, fresh air costs. How much depends on the type and how well the ventilation system is designed / installed / commissioned / maintained.

howman wrote: »

2.5 to 3 ac/hr

If you achieve 2.5 to 3 ach and you rely on trickle vents for your ventilation then you will have poor indoor air quality and all the associated issues. Period.

howman

would you not have the necessary pressure difference to create the flow through the vents?


Do you have the required temp difference to create an efficient h/e?

Would any heat recovered be lost to your attic?


then account for the running costs of the fan

MicktheMan

howman wrote: »

1. would you not have the necessary pressure difference to create the flow through the vents?


2.Do you have the required temp difference to create an efficient h/e?

3.Would any heat recovered be lost to your attic?


4.then account for the running costs of the fan

1. In an air tight house, no.
2. Please explain what you mean by "an efficient h/e"
3. Down to the location & design of the system / ductwork.
4. Very little. Funny, isn't it, I don't very often hear of people complaining about the cost of running their fridge. Yet, when you compare the function of a ventilation system to a fridge, they are very similar. Both do important but effectively non-essential work (in that, there are other means to do what they do without purchasing equipment). If you had neither you would have inefficiencies in wasted heat and spoiled food. Imo, not installing a properly designed ventilation system in an airtight house is akin to storing food in the pantry (which was done in our grandparents time).

Finally, there are more choices to adequately ventilate a house than trickle vents or MVHR. Have you considered other options such as MEV or DCV?

howman

MicktheMan wrote: »

1. In an air tight house, no.
2. Please explain what you mean by "an efficient h/e"
3. Down to the location & design of the system / ductwork.
4. Very little. Funny, isn't it, I don't very often hear of people complaining about the cost of running their fridge. Yet, when you compare the function of a ventilation system to a fridge, they are very similar. Both do important but effectively non-essential work (in that, there are other means to do what they do without purchasing equipment). If you had neither you would have inefficiencies in wasted heat and spoiled food. Imo, not installing a properly designed ventilation system in an airtight house is akin to storing food in the pantry (which was done in our grandparents time).

Finally, there are more choices to adequately ventilate a house than trickle vents or MVHR. Have you considered other options such as MEV or DCV?

hard to argue with the above

i had got it into my head that trickle vents / open window would do the trick but perhaps not

being honest..not even aware of DCV or MEV..just looking it up now

howman

MicktheMan wrote: »

1. In an air tight house, no.
2. Please explain what you mean by "an efficient h/e"
3. Down to the location & design of the system / ductwork.
4. Very little. Funny, isn't it, I don't very often hear of people complaining about the cost of running their fridge. Yet, when you compare the function of a ventilation system to a fridge, they are very similar. Both do important but effectively non-essential work (in that, there are other means to do what they do without purchasing equipment). If you had neither you would have inefficiencies in wasted heat and spoiled food. Imo, not installing a properly designed ventilation system in an airtight house is akin to storing food in the pantry (which was done in our grandparents time).

Finally, there are more choices to adequately ventilate a house than trickle vents or MVHR. Have you considered other options such as MEV or DCV?

mick thanks again

think DCV could be my answer..will investigate further

BryanF

howman wrote: »

mick thanks again

think DCV could be my answer..will investigate further

More suited to retrofit projects.

Philburns

afinador wrote: »

We did a seriously deep retrofit and just the atw HP, no underfloor, and 2 large standard rads downstairs...HP copes with all the hot water and space heat requirement

I am looking at doing a retrofit myself. Out of interest what HP did you fit?

howman

BryanF wrote: »

More suited to retrofit projects.

How so?

BryanF

howman wrote: »

How so?

A new build is a 'clean slate' - the question is why wouldn't you attain the best air-tightness level and install MVHR?

DCV extracts from the bathrooms to a centralised location and is then vented. each room then has a RH fan over a 4inch 'hole in the wall vent' supplying fresh 'cold' air to the house as required. in retro-fitting these work well, where achieve air-tightness might be more difficult and running duct-work may not be as easy as in a new build.

sydthebeat

howman wrote: »

2.5 to 3 ac/hr

howman wrote: »

window vents

firstly, 2.5 / 3 ac/hr would not comply with building regulations.
That would be an air tightness result of 50 / 60 m3 :eek:

ill assume you mean 2.5 / 3 m3 permeability.

secondly, did you realise that if you do achieve a permeability of 2.5 / 3 m3, you MUST increase your total window ventilation areas by 40%

dc14

I'm really going in circles here trying to find a solution to my heating requirements. I was sold on the idea of A2W heatpumps and need to pick one now. My builder is s-snip-. He's recommending -snip- as he says it's about €2k cheaper than t-snip-, but I've read bad reviews for both of these.

I was thinking of biting the bullet and going for the more costly-snip- as I want this to last a long time without issues with freezing over in winter or massive electricity costs when the immersion back-up kicks in.

However, I've now seen bad reviews for -snip-forum saying that there was a TV show about these units & lots of customer complaints.

So, what do I do now? I know the bad reviews for-snip- & maybe they've ironed these issues out, but they are way more costly than the others, so is it worth taking the risk?

Am I looking for the impossible in my search for a reliable, efficient heatpump which offers savings in the long term?

My house has a provisional BER A3 rating, so it's well insulated. Maybe I should have just stuck with the tried & tested gas boiler

bartbu

dc14 wrote: »

I'm really going in circles here trying to find a solution to my heating requirements. I was sold on the idea of A2W heatpumps and need to pick one now. My builder is suggesting -snip-. He's recommending t-snip- as he says it's about €2k cheaper than -snip- but I've read bad reviews for both of these.

I was thinking of biting the bullet and going for the more c-snip- as I want this to last a long time without issues with freezing over in winter or massive electricity costs when the immersion back-up kicks in.

However, I've now seen bad reviews for-snip- forum saying that there was a TV show about these units & lots of customer complaints.

So, what do I do now? I know the bad reviews -snip- & maybe they've ironed these issues out, but they are way more costly than the others, so is it worth taking the risk?

Am I looking for the impossible in my search for a reliable, efficient heatpump which offers savings in the long term?

My house has a provisional BER A3 rating, so it's well insulated. Maybe I should have just stuck with the tried & tested gas boiler

Know the feeling bud. Thinking of going -snip- also. Where did you read the bad reviews. Impossible to find one well recommended I find. Anyone any experience of -snip-. There a cork based company? ?

howman

dc14 wrote: »

-snip-maybe they've ironed these issues out, but they are way more costly than the others, so is it worth taking the risk?

Am I looking for the impossible in my search for a reliable, efficient heatpump which offers savings in the long term?

My house has a provisional BER A3 rating, so it's well insulated. Maybe I should have just stuck with the tried & tested gas boiler

know how you feel, I have done full circle of A2W heat pump with MHVR and solar to your normal boiler and back again...
had some good discussions with genuine, knowledgeable people of late and have decided to go with Geo heat hump with MHVR..seems to be the best fit...have more confidence in the geo than A2W heat pumps and the material costs are similar

Mixupat

I spent a lot of time and research recently and have come to the conclusion that Geothermal is the best solution. I received advise from people here on boards as well as people in the trades. I talked to a good few companies who do both air and ground source also and this helped form my opinion. At the beginning there was no way I was going ground source, I was air source all the way...

THE DON FANUCCI

any good air to water heat pump manufacturers? what's the best make anybody know?

MENACE2010

Hi
PM me.. I have a brand and supplier i can recommend .. but I cannot <snip> tell you <snip> in the post

Doorcase

Hi every one. Thining of putting in Mitisbishi Ecodan in 2733 sq foot house. Just wondering how eveyone is getting on over the past few years with their A2W heat pumps.

MENACE2010

Hi
So on what I have posted so far we are happy with what we have with the thermia brand. it works as advertised. I'm not sure though what you are looking for as the size of the house and the pump cannot be compared to another house with the same Square footage etc as there are so many variables per house that its near impossible to give you a like for like experience. I'm happy what the pump does and the bills are not "massive" , bit of common sense and the right settings does help .

adrianm1234

MENACE2010 wrote: »

Hi
PM me.. I have a brand and supplier i can recommend .. but I cannot <snip> tell you <snip> in the post

Can you pm me the info you. Much appreciated