Heat Pumps - post here.

adrianm1234

interested in info also . please pm info

sheff the ref

Lets say in mid summer (yes Irish weather.....) you get a few individual nights that are well below 18 degrees, but the temperature picks back up again.

The heatpump will kick in and therefore you will have underfloor heating up. However the floor will not heat quickly enough to have heat when you need it and the floor will retain heat which is a nuisance as the temperature has risen again

MENACE2010 wrote: »

Hey
We have a stove.5kw version. Heats up the living area. I tried hardwood logs but since converted to compressed saw dust logs. Better performance once the stove is hot we can burn one of these logs every two hours. .if we do more the house gets too hot ..
I leave the heat pump on and set cut off temperature to 18 degrees once it hits that outside the pump will not kick in

Denisoftus

Nibe 320 Water LUX mode question. I have enabled 3 hours temporary lux mode and APP on the phone displayed Immersion in use (Additional heating BT63), same time pump was showing Additional: blocked. So now I'm not sure is its being used or not, I don't have smart ESB meter, so I could not confirm power consumption at the time, the Immersion is 7Kwt.

Can temp LUX use Immersion even its block in other settings?

ct98

I have a Daikin air to water split heat pump installed for <5 yrs. I now have a fault with PC board. With the benefit of hindsight, I would not purchase a heat pump. They are too many parts which can and will fail. These parts are very expensive, repairs are controlled by 1 agent (no competition). Also, we are now without heating for 3 weeks which is ok as it's Summer but could as easily been winter.

I have raised my concerns directly with Daikin and they have not bother responding. Please keep in mind there is multiple potential parts that can/ will go wrong and therefore making the unit very expensive. I hope this helps inform those considering heating options.

ct98

I have a Daikin air to water split heat pump installed for <5 yrs. I now have a fault with PC board. With the benefit of hindsight, I would not purchase a heat pump. They are too many parts which can and will fail. These parts are very expensive, repairs are controlled by 1 agent (no competition). Also, we are now without heating for 3 weeks which is ok as it's Summer but could as easily been winter.

I have raised my concerns directly with Daikin and they have not bother responding. Please keep in mind there is multiple potential parts that can/ will go wrong and therefore making the unit very expensive. I hope this helps inform those considering heating options.

ct98

I have a Daikin air to water split heat pump installed for <5 yrs. I now have a fault with PC board. With the benefit of hindsight, I would not purchase a heat pump. They are too many parts which can and will fail. These parts are very expensive, repairs are controlled by 1 agent (no competition). Also, we are now without heating for 3 weeks which is ok as it's Summer but could as easily been winter.

I have raised my concerns directly with Daikin and they have not bother responding. Please keep in mind there is multiple potential parts that can/ will go wrong and therefore making the unit very expensive. I hope this helps inform those considering heating options.

Wegian

ct98 wrote: »

I have a Daikin air to water split heat pump installed for <5 yrs. I now have a fault with PC board. With the benefit of hindsight, I would not purchase a heat pump. They are too many parts which can and will fail. These parts are very expensive, repairs are controlled by 1 agent (no competition). Also, we are now without heating for 3 weeks which is ok as it's Summer but could as easily been winter.

I have raised my concerns directly with Daikin and they have not bother responding. Please keep in mind there is multiple potential parts that can/ will go wrong and therefore making the unit very expensive. I hope this helps inform those considering heating options.

Thanks for the feedback. What is your backup for hot water?

ct98

Hi, we dont have any backup for hot water. The immersion part of the heat pump is functioning, so we have hot water but no floor heating.

Shanaknocker

Thanks to all who have posted here, great source of information.

I am currently researching for a new build (220msq)and hopefully starting soon. I just received my parliamentary DEAP report and it states that i have a heating requirement of 4932 kwhr/yr and hot water requirement of 3560 kwhr/yr and a heat loss of 230kwper msq. I take it that if i divide 2932 by 220, il get kw per meter sq (22.418).
I just spoke with a rep and he suggest i use a 6kw Daikin Altherma integrated clinder (260 liter tank) with low temp rads (no more than 136 sections) estimating 10 k for installation including rads and pipework, with a cost of 3 to €400 a year.

does this sound right??????????

ct98 wrote: »

I have a Daikin air to water split heat pump installed for <5 yrs. I now have a fault with PC board. With the benefit of hindsight, I would not purchase a heat pump. They are too many parts which can and will fail. These parts are very expensive, repairs are controlled by 1 agent (no competition). Also, we are now without heating for 3 weeks which is ok as it's Summer but could as easily been winter.

I have raised my concerns directly with Daikin and they have not bother responding. Please keep in mind there is multiple potential parts that can/ will go wrong and therefore making the unit very expensive. I hope this helps inform those considering heating options.

Sorry for picking you out CT98,
my rep seems quite approachable and has directed me in different directions in relation to other aspects. Have you approached where you purchased the product or gone directly to Daikin. What other issues have you encountered????
what system would you go for if not HP?

Water John

Have not heard any major problems with HP's. There are few parts to go wrong. Same as a fridge really.

ct98

There are problems with Heatpumps, believe me I was without heating/hot water for almost 4 weeks due to brakdown of outdoor unit of a Daikin split system. Initially I was told it was the PCB board, but later told it was PCB Board, Compressor and Fan motor. These parts are not repairable and are very expensive to replace.

My unit was less than 5 years in running (only 3 yr warranty on my unit) and I contacted Daikin directly and I found them extremely unhelpful and even rude questioning the truth of what I was saying.

The unit is now running and I have since spoke with heat pump engineers (not Daikin) and they cannot understand how all 3 could fail at same time and since I should have looked for proof of failure. However the Daikin agent said, there is no protection to prevent series failure (i.e. fuse if compressor failed).

froshtyv

ct98 wrote: »

There are problems with Heatpumps, believe me I was without heating/hot water for almost 4 weeks due to brakdown of outdoor unit of a Daikin split system. Initially I was told it was the PCB board, but later told it was PCB Board, Compressor and Fan motor. These parts are not repairable and are very expensive to replace.

My unit was less than 5 years in running (only 3 yr warranty on my unit) and I contacted Daikin directly and I found them extremely unhelpful and even rude questioning the truth of what I was saying.

The unit is now running and I have since spoke with heat pump engineers (not Daikin) and they cannot understand how all 3 could fail at same time and since I should have looked for proof of failure. However the Daikin agent said, there is no protection to prevent series failure (i.e. fuse if compressor failed).

Did you ever get your heat pump serviced as a matter of interest?

0lddog

Have any of you with heat pumps not found

http://www.refrigeration-engineer.com/forums/forumdisplay.php?78-Heat-Pumps

?

sheff the ref

ct98 wrote: »

With the benefit of hindsight, I would not purchase a heat pump. They are too many parts which can and will fail. These parts are very expensive, repairs are controlled by 1 agent (no competition). Also, we are now without heating for 3 weeks which is ok as it's Summer but could as easily been winter.

That is an interesting observation but the problem with oil and rads is that you need some form of green energy to satisfy the regulations and solar alone wont do that.

sheff the ref

Would you run a heatpump with rads for an annual cost as low as that?

Shanaknocker wrote: »

Thanks to all who have posted here, great source of information.

I am currently researching for a new build (220msq)and hopefully starting soon. I just received my parliamentary DEAP report and it states that i have a heating requirement of 4932 kwhr/yr and hot water requirement of 3560 kwhr/yr and a heat loss of 230kwper msq. I take it that if i divide 2932 by 220, il get kw per meter sq (22.418).
I just spoke with a rep and he suggest i use a 6kw Daikin Altherma integrated clinder (260 liter tank) with low temp rads (no more than 136 sections) estimating 10 k for installation including rads and pipework, with a cost of 3 to €400 a year.

does this sound right??????????



Sorry for picking you out CT98,
my rep seems quite approachable and has directed me in different directions in relation to other aspects. Have you approached where you purchased the product or gone directly to Daikin. What other issues have you encountered????
what system would you go for if not HP?

Water John

Its down to the thermal envelope sealing and insulation of the house.
Yes about €400 tends to be the cost for HP plus UFH on a very good BER. Using Aluminium rads instead should make little difference.

Condenser

Water John wrote: »

Its down to the thermal envelope sealing and insulation of the house.
Yes about €400 tends to be the cost for HP plus UFH on a very good BER. Using Aluminium rads instead should make little difference.

It'll make a lot of difference. Alu rads will need 45C to be any good. You lose 2-3% efficiency for every degree increase so you'll be down at least 20% but more likely 30% in efficiency not to mention the extra strain on the compressor which means premature failure but I doubt the rep will mention that.

Water John

30% of 400 is a diff of €150 in the year. To me that counts as a little diff.
I would not be expert on 'strain' on a HP. I thought they were pretty robust with little breakdown.
So would you very circumspect about the twin scrollers that also heat hot water to 55/60 C?

Personally, I would prefer UFH to Alu Rads.

Condenser

Water John wrote: »

30% of 400 is a diff of €150 in the year. To me that counts as a little diff.
I would not be expert on 'strain' on a HP. I thought they were pretty robust with little breakdown.
So would you very circumspect about the twin scrollers that also heat hot water to 55/60 C?

Personally, I would prefer UFH to Alu Rads.

Firstly, I would find it unlikely that you would heat that house with the mentioned unit for that money. Then you need to consider that the running cost will increase approx. 5% year on year so you start off at €400 or €550 depending on ufh or alu. Then the following year its €420 vs €577.5 and the year after that €441 vs 606.37 and so forth for the life of the unit with the spread getting wider by the year.


Regarding longevity. In order to increase temp you need to increase gas pressure which strains the components. In lay mans terms its like a guy going to the gym and putting 50kg on the bar and knocking out twenty repetitions but stick 70kg on the bar and he'll be done at 10 reps.A heat pump can handle low temp production all day but high temperature degrades the equipment quickly regardless of the compressor used. Heating water to 60C with any refrigerant other than ammonia or CO2 is madness and will destroy your heat pump in short order.

Water John

Condenser, The second part of your post, I am not in a position to contest as it is not my area. But if what you say is true, then many manufacturers, including some very credible makers are being irresponsible.

In part one you are assuming an energy inflation of 5% per year. Doesn't matter what you heat the house with, that will apply.

Yes, I have been involved in supplying many clients with UFH and around €400 tends to be the cost of heating per year. Needs a good sealed envelope and high level of insulation but no insurmountable.

Condenser

Water John wrote: »

Condenser, The second part of your post, I am not in a position to contest as it is not my area. But if what you say is true, then many manufacturers, including some very credible makers are being irresponsible.

In part one you are assuming an energy inflation of 5% per year. Doesn't matter what you heat the house with, that will apply.

Yes, I have been involved in supplying many clients with UFH and around €400 tends to be the cost of heating per year. Needs a good sealed envelope and high level of insulation but no insurmountable.

Yes they are but are you surprised. In the world of business anything can and will go in order to get a competitive edge. Theres very few moral companies out there.
My point about energy inflation is not that it increases, it is the fact that when your running costs are higher than they could be the increase is proportional to this higher cost and therefore becomes significant over the lifetime of the system. Same applies to comparing a GSHP to ASHP. Installation cost might be 3-4k more but half the running costs. When you work it out over the lifetime the savings are multiple times the initial investment.

sheff the ref

10 years ago, a heatpump was only suited to Underfloor. Based on the sequence of posts above, it seems as though nothing has changed. Running radiators off a heatpump is not really viable it would appear.

Water John

Sheff, you just need to ask around to see if HP's are failing as being said by some posters.
Some installations would use UFH downstaires and alu rads upstairs.

Basically, talk to some plumbers.
I would like to hear further opinions on HP's too. I have an open mind on it.

Condenser

Water John wrote: »

Sheff, you just need to ask around to see if HP's are failing as being said by some posters.
Some installations would use UFH downstaires and alu rads upstairs.

Basically, talk to some plumbers.
I would like to hear further opinions on HP's too. I have an open mind on it.

What's the point in talking to plumbers. Plumbers don't have the first clue about how a heat pump works. Most will tell you that themselves. You need to talk to a refrigeration engineer.


Physics hasn't changed in the last 10yrs so heat pumps suitability to heating rads hasn't changed either.

sheff the ref

Water John wrote: »

Sheff, you just need to ask around to see if HP's are failing as being said by some posters.
Some installations would use UFH downstaires and alu rads upstairs.

Basically, talk to some plumbers.
I would like to hear further opinions on HP's too. I have an open mind on it.

I worked in the area of Geothermal back 10 or 11 years ago, so I would have strong knowledge of the systems. However the following variables have changed

1.Insulation is now of a higher spec, meaning that the same heat requirement may not be there. Triple glazed windows were very rare back then.

2.Air to Water systems are a lot more common meaning that there is an alternative without needing a borehole or ground collector

3.Controls have advanced significantly

4.Aluminium radiators are very common now.

I accept that rads are used upstairs, but the heat requirement for bedrooms is not as demanding as for downstairs living areas.

Basically as pointed out by Condenser, the temperature requirement for underfloor heating is far less than for radiators. This means that the heatpump can run continuously without being stressed.

On the other hand, higher insulation specs these days mean that the same heat requirement is not there, so perhaps heating using radiators may not necessarily overwork a heatpump at all, even at a higher temperature. Lets say that underfloor requires 30 degrees heat and aluminum rads require 45 degrees heat. The reality is that the heatpump will have to work a lot harder to produce 15 degrees more heat and will cost more money to produce that heat

The big question then is on a winters day of say 4 degrees outside temperature, how long will the (possibly overworked) heatpump need to run for to heat the house using rads, and how long will it need to run (casually) to top up the heat in the ground?

ferryman35

A heat pump can work fine with steel rads....if they are suitably sized - a larger rad running at a low temperature will deliver the same amount of heat to a room as a smaller rad operating at a higher temperature.

Efficiency falls as the temperature increases....for a gas or oil boiler as well as a heatpump - flow temperatures in the mid 30's to mid 40's should be easily deliverable with a heatpump - but you won't run a heatpump like you would a boiler on a start stop basis - whether it's heating through underfloor or radiators - cycling has a big impact on heatpump life and in this case a buffer can make a huge difference. With underfloor the screed is much like a buffer whereas with rads you don't have the screed to fall back on.

sheff the ref

Wouldnt mind seeing a setup where there are oversized rads throughout the house and a buffer tank in operation.

Ultimately even oversized rads would still need a higher temperature feed than underfloor

ferryman35 wrote: »

A heat pump can work fine with steel rads....if they are suitably sized - a larger rad running at a low temperature will deliver the same amount of heat to a room as a smaller rad operating at a higher temperature.

Efficiency falls as the temperature increases....for a gas or oil boiler as well as a heatpump - flow temperatures in the mid 30's to mid 40's should be easily deliverable with a heatpump - but you won't run a heatpump like you would a boiler on a start stop basis - whether it's heating through underfloor or radiators - cycling has a big impact on heatpump life and in this case a buffer can make a huge difference. With underfloor the screed is much like a buffer whereas with rads you don't have the screed to fall back on.

Water John

I would def agree with the buffer tank with HP where any rads are taken off.

I still see the alu rads as the best rad option for HP. Dissipate the heat much quicker so can run a fairly low temp. Buffer tank reduces cycling.

Summer is Coming

I've received quotes back from a few suppliers for ground source heat pumps and although I have given all the necessary information (including the DEAP xml file showing heat loss etc) they have all come back with quite different proposals.

The 1st has quoted for an 8.7kw Stiebel Eltron heat pump with a 400L hot water cylinder
The 2nd has quoted for an 8.3kw Waterfurnace heat pump and recommends getting a separate 300L hot water cylinder.
While the 3rd has quoted for an 6kw Thermia heat pump with a 180L integrated hot water cylinder.
Naturally the first has given me the highest quote and 3rd the lowest.

I intend using underfloor heating and as my heat loss should be close to passive levels (fingers crossed) I reckon the 6kw may be best to prevent the pump cycling on and off however the total water volume of 180ltrs has me concerned.

The house will be a 4bed with 1 main bathroom, 2 en-suites and a WC along with the kitchen and utility so while the 180L may be okay at present with only 2 occupants I think the 300L seems safer once kids come along and more washing etc is to be done.

The issue I have is that the 6kw has a lower SPF% compared to the others (396% vs 407% & 435%) so increasing the water volume with that pump affects my EPC in the DEAP file and causes me to fail.
I'm already assuming an air permeability of 1 m3/(hr.m2) @ q50 so I don't want to cut that any further incase I can't meet it.

Any suggestions on which I should go with?

I'm leaning towards going with the 6kw with the 180L tank and adding an additional buffer tank in a few years then if required.

ferryman35

Summer is Coming wrote: »

I've received quotes back from a few suppliers for ground source heat pumps and although I have given all the necessary information (including the DEAP xml file showing heat loss etc) they have all come back with quite different proposals.

The 1st has quoted for an 8.7kw Stiebel Eltron heat pump with a 400L hot water cylinder
The 2nd has quoted for an 8.3kw Waterfurnace heat pump and recommends getting a separate 300L hot water cylinder.
While the 3rd has quoted for an 6kw Thermia heat pump with a 180L integrated hot water cylinder.
Naturally the first has given me the highest quote and 3rd the lowest.

I intend using underfloor heating and as my heat loss should be close to passive levels (fingers crossed) I reckon the 6kw may be best to prevent the pump cycling on and off however the total water volume of 180ltrs has me concerned.

The house will be a 4bed with 1 main bathroom, 2 en-suites and a WC along with the kitchen and utility so while the 180L may be okay at present with only 2 occupants I think the 300L seems safer once kids come along and more washing etc is to be done.

The issue I have is that the 6kw has a lower SPF% compared to the others (396% vs 407% & 435%) so increasing the water volume with that pump affects my EPC in the DEAP file and causes me to fail.
I'm already assuming an air permeability of 1 m3/(hr.m2) @ q50 so I don't want to cut that any further incase I can't meet it.

Any suggestions on which I should go with?

I'm leaning towards going with the 6kw with the 180L tank and adding an additional buffer tank in a few years then if required.

There's another make & model out there that could be worth your while consider. The one I have in mind is an inverter model so it will modulate to your heat loss load anywhere between 2.5 & 12kw - but it takes the ground loop capacity into account so it won't be trying to soak 12 kw out or your ground loop if the loop can only supply 8kw. It's SCOP is 5.43 - and it has industry leading hot water capacity of 300L from a 229l buffer. Feel free to send me a pm if you'd like more information.