Air 2 Water Heat Pump Costs

Curious Geroge

Pricing at the moment. If you don't mind sharing what it cost you or what quotes you received, it would be great.

Daikin 16Kw was €6500 including a 300ltr cylinder.
Heliotherm 16Kw seems to be in the region of €15k

mullr

Hi, I'm in the same process - I got a quote of €9'850 for a 13kW Thermia Atec Air to Water heat pump and €6,400 for the underfloor heating (ground floor & first floor) supply only plus VAT.

Have no idea if that is good or bad. Are Thermia any good?
All advice welcome.
The insulation in the house is very hight with a high airtightness.
thanks

kcb

Try Reservoir in Little Island

mullr

Kcb,

Will do thanks

fclauson

Curious Geroge wrote: »

Pricing at the moment. If you don't mind sharing what it cost you or what quotes you received, it would be great.

Daikin 16Kw was €6500 including a 300ltr cylinder.
Heliotherm 16Kw seems to be in the region of €15k

What is you heat demand - a 16Kw HM is massive ?

Curious Geroge

fclauson wrote: »

What is you heat demand - a 16Kw HM is massive ?

3000sq ft over 3 floors. Danfoss lads got back with a requirement for a 12kW. Would this be more suitable ?

fclauson

ok - back to physics-

have you done a PHPP calc (and if not why not !!)

this will give you the demand - DEAP just fails to do this correctly

MOTM

fclauson wrote: »

this will give you the demand - DEAP just fails to do this correctly

Just as well its not a design tool so.

fclauson

MOTM wrote: »

Just as well its not a design tool so.

true - and its not much of a ratings tool either as it favours less insulated builds !!!!
So I do wonder as to its value which is what I have said in my DEAP public consultation feedback

Curious Geroge

fclauson wrote: »

ok - back to physics-
I
have you done a PHPP calc (and if not why not !!)

this will give you the demand - DEAP just fails to do this correctly

Thanks fclauson, is DEAP and a BER assessment the same ? We're early in construction and still making structural decisions. Is the PHPP something you fill out online or do I hire someone to complete one ?

fclauson

Yes - DEAP is the s/w used to calculated your BER - its available from the SEAI website

unfortunately for a low energy build it can turn out nonsense so I would get a PHPP done

MOTM

fclauson wrote: »

Yes - DEAP is the s/w used to calculated your BER - its available from the SEAI website

unfortunately for a low energy build it can turn out nonsense so I would get a PHPP done

Is this because of the difficulty in lower energy dwellings meeting the Part L renewables requirement?

MOTM

Curious Geroge wrote: »

Thanks fclauson, is DEAP and a BER assessment the same ? We're early in construction and still making structural decisions. Is the PHPP something you fill out online or do I hire someone to complete one ?

Bear in mind that by law, for a new dwelling you have to carry out the DEAP assessment for 2 reasons:
1) A BER Cert is required by law for all new dwellings
2) To demonstrate compliance with Part L (the energy efficiency and energy conservation part) of the Irish building regulations.

fclauson

MOTM wrote: »

Is this because of the difficulty in lower energy dwellings meeting the Part L renewables requirement?

Partially it also "guides" you that you have a 'better' build with lower spec u-values

MOTM

fclauson wrote: »

Partially it also "guides" you that you have a 'better' build with lower spec u-values

With the renewables requirement, this is for Part L checked in DEAP using guidance in the shape of TGD L, so perhaps you're barking up the wrong tree by trying to change DEAP rather than Part L/TGD L?

If DEAP calculates lower fabric heat loss (better insulation, thermal bridging, air tightness), then there's less space heat demand. If there's less space heat demand, then the renewable space heat source has less work to do.

What's missing is that TGD L went for an absolute renewables figure rather than putting a figure on what would be a reasonable proportion. So the shortfall in renewable space heating is, according to TGD L, to be made up with other renewables.

As DEAP isn't a design tool, and is not there to define how building regulations should be met, all it can do is provide a comparison between different dwellings (BER) and check that the dwelling meets the Part L requirements using TGD L. It sounds like your beef is with how the regs checks work and the guidance in TGD L...

(Mods, sorry for going off topic, but as it came up in this thread, I responded in this thread).

Curious Geroge

PHPP seems to be somewhere between €700 and €1000. I'd need some real justification to go and get this done since I'm not building a passive house, I'm building a house that is well insulated, good quality windows, underfloor heating and the MVHR put in. I understand that the heat pump would be the main priority hear but wouldn't the best input on what kW is required come from those that deal with supplying these and not from a report based on figures.

Old Jim

What do you get for your 700-1000 for your PHPP analysis? Is it a report with your determined heat demand or would whoever prepares it provide options on the best way of meeting this demand?
I am struggling at the moment on a suitable heating system for my new build and wonder what type of professional is in the best position to advise

BryanF

Curious Geroge wrote: »

PHPP seems to be somewhere between €700 and €1000. I'd need some real justification to go and get this done since I'm not building a passive house, I'm building a house that is well insulated, good quality windows, underfloor heating and the MVHR put in. I understand that the heat pump would be the main priority hear but wouldn't the best input on what kW is required come from those that deal with supplying these and not from a report based on figures.

I get that you'd need justification to pay for a phpp assessment and there's plenty written elsewhere in this forum on that topic.

why would you assume that a heat pump salesman would be willing to anything more than a rule of thumb kw demand?

'a report based on figures' as you put it, of your houses particulars, is a better way to compare different heating systems than talking to a salesman about his/her product.

but sure maybe the 12kW will do, or maybe you should go to a 16kw unit, as you dont know what your homes heat loss/gain or KWH demand will be, but sure your still making structural decisions on site? so maybe heating is not a high priority, though its an expensive guess to be leaving to a product salesman..

fclauson

Just to put this in perspective my Hp is 2kw with an immersion backup

fclauson

MOTM wrote: »

With the renewables requirement, this is for Part L checked in DEAP using guidance in the shape of TGD L, so perhaps you're barking up the wrong tree by trying to change DEAP rather than Part L/TGD L?

If DEAP calculates lower fabric heat loss (better insulation, thermal bridging, air tightness), then there's less space heat demand. If there's less space heat demand, then the renewable space heat source has less work to do.

What's missing is that TGD L went for an absolute renewables figure rather than putting a figure on what would be a reasonable proportion. So the shortfall in renewable space heating is, according to TGD L, to be made up with other renewables.

As DEAP isn't a design tool, and is not there to define how building regulations should be met, all it can do is provide a comparison between different dwellings (BER) and check that the dwelling meets the Part L requirements using TGD L. It sounds like your beef is with how the regs checks work and the guidance in TGD L...

(Mods, sorry for going off topic, but as it came up in this thread, I responded in this thread).

MOTM. Your outline is perfect - my beef is DEAP is being used as a guide when it's just plane wrong Eg why does it apply the junction psi value to the surface area and not the junction length !!

BryanF

fclauson wrote: »

Eg why does it apply the junction psi value to the surface area and not the junction length !!

i never understood this!

if you have 0.01w/mk for 95% and there is a steel with .15w/mk what do you put in for the one option your given

fclauson

BryanF wrote: »

i never understood this!

if you have 0.01w/mk for 95% and there is a steel with .15w/mk what do you put in for the one option your given

I know we are off topic - but Bryan - its http://www.seai.ie/Your_Building/BER/BER_FAQ/FAQ_DEAP/Building_Elements/How_should_thermal_bridging_be_accounted_for_in_DEAP_.html tha you need to use

fclauson

Curious Geroge wrote: »

PHPP seems to be somewhere between €700 and €1000. I'd need some real justification to go and get this done since I'm not building a passive house, I'm building a house that is well insulated, good quality windows, underfloor heating and the MVHR put in. I understand that the heat pump would be the main priority hear but wouldn't the best input on what kW is required come from those that deal with supplying these and not from a report based on figures.

Back to the OP - €1000 could be the saving you make on choosing the wrong HP - or incorrectly selecting you insulation spec

a bad choice now means a lifetime of costs

MOTM

fclauson wrote: »

MOTM. Your outline is perfect - my beef is DEAP is being used as a guide when it's just plane wrong Eg why does it apply the junction psi value to the surface area and not the junction length !!

Looking at DEAP appendix K and the Excel version of DEAP on the SEAI site, DEAP needs to determine the fabric heat loss: the sum of the UxA heat loss from the plane elements [W/K] and the heat loss from thermal bridging [W/K]. Call the heat loss from thermal bridging Htb.
While the figure entered in DEAP is the Y factor, there are two equations that can derive Htb:
1) Htb = [Area of exposed elements]*Y
Or
2) Htb = Sum of all [junction lengths * PSI values]

Htb = Htb.......
So if you have the PSI values, junction lengths and exposed element areas you can determine the Y value for entry into DEAP. Once you have the PSI, junction lengths, element areas and resulting Y value, then is the Htb value not correct?

fclauson

MOTM wrote: »

Looking at DEAP appendix K and the Excel version of DEAP on the SEAI site, DEAP needs to determine the fabric heat loss: the sum of the UxA heat loss from the plane elements [W/K] and the heat loss from thermal bridging [W/K]. Call the heat loss from thermal bridging Htb.
While the figure entered in DEAP is the Y factor, there are two equations that can derive Htb:
1) Htb = [Area of exposed elements]*Y
Or
2) Htb = Sum of all [junction lengths * PSI values]

Htb = Htb.......
So if you have the PSI values, junction lengths and exposed element areas you can determine the Y value for entry into DEAP. Once you have the PSI, junction lengths, element areas and resulting Y value, then is the Htb value not correct?

Perfect again MOTM - DEAP is flawed and useless as both a design tool and as a ratings tool

Curious Geroge

BryanF wrote: »

I get that you'd need justification to pay for a phpp assessment and there's plenty written elsewhere in this forum on that topic.

why would you assume that a heat pump salesman would be willing to anything more than a rule of thumb kw demand?

'a report based on figures' as you put it, of your houses particulars, is a better way to compare different heating systems than talking to a salesman about his/her product.

but sure maybe the 12kW will do, or maybe you should go to a 16kw unit, as you dont know what your homes heat loss/gain or KWH demand will be, but sure your still making structural decisions on site? so maybe heating is not a high priority, though its an expensive guess to be leaving to a product salesman..

Fiar point(s) BryanF. Should I wait for the PHPP until we have the strcuture in place and at least decided on windows ? I'd fear that doing it based on what we "plan" todo versus what we actually do might mean I need to get the report done twice ?

fclauson

Curious George - you need to get it done now as it may turn up you need a wider cavity or a deeper layer of insulation under the floor

You then work with your PHPP consultant as the build progresses (that's normally all in the fee)

The PHPP will show you what levels of insulation you need now (prior to build) and then takes into account any changes you do as you go along - its a continuous tuning process -

If done right it will show you what the heat demand is and hence the HP you require

Trust me its the right way to go