Heat Pumps - post here.

JD6910

Tommyboy08 wrote: »

Ochsner DX unit has a cop of 5.1(unsure if their installers will even fit this model in Ireland you would have to check with them)
ochsner brine unit has a cop of 4.7,
Heliotherm brine unit has cop of 4.9
Heliotherm DX unit has a cop of 5.8
Nibe brine unit has a cop of 4.3

so yes ochsner and heliotherm are the rolls royce and closely followed by nibe?

any drawbacks with ochnser and heliotherm in terms of support, maintanence, spare part availibility etc....?????

who is the best agent to purchase one from???

Tommyboy08

JD6910 wrote: »

so yes ochsner and heliotherm are the rolls royce and closely followed by nibe?

any drawbacks with ochnser and heliotherm in terms of support, maintanence, spare part availibility etc....?????

who is the best agent to purchase one from???

Well 35% is hardly close :-)
I doubt theirs any drawback with either installer, just look here on boards for feedback and its all good
As far as I know both companies have a select few installers so as to keep standards high, personally I've never been called out to look at any of their systems and that's a good thing as far as I'm concerned,
Just google both units and you'll find agents very easily

Curious Geroge

Currently reviewing the Daikin heat pump, its a 16Kw for a 3000sq ft house. At about 6k commissioned I'm asking why the same 16Kw Heliotherm is about 15k. Is there really that much of a quality difference. I didn't see Daikin mentioned on the one to aviod list.

Would be great if anyone could recommend other manufacturers that I should talk too before I commit.

Thanks

0lddog

Daikin are a BIG NAME in aircon / heat pumps

Dont know specifics on Altherma ( I presume ) vs Heliotherm

I'd be looking at

Nominal COP ( & how COP derates with outside temp )

Min outside temp for system to do meaningful work

Warranty

Stability of supplier

I'd also have a good browse around the likes of

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

( Daikin should get a lot of mention as its a very big seller )

HTH

Olddog

P.S. Jap Yen going down the pan in the last few months

L driver

anyone ever use IDM heatpumps?

engineermike

L driver wrote: »

anyone ever use IDM heatpumps?

Hi,
I have taken one out of a property & replaced it with a Nibe a while back. However I don't think it was so much the pump unit that was the let down, rather the installer poorly matched it for the requirement & did an awful job of installation.
Original sales & install company are gone bust now. Not hard to see why! :P
mike f

afinador

Hi

We've started on a retro fit to a 70's semi-d. Aiming to get to Passiv standard, so lots of insulation and an ACH of .6. Small enough house, 150msq. Sorted on the HRV, but a bit baffled by the range of air to water heat pumps available. Looking hard at the Panasonic Aquarea range, specifically the 6kw mono-bloc.
Anyone have any experience with this unit?

Tiler Durden

Anyone have anything to say about a Weider ground source heat pump, 9KW?

maysville

We're starting a new build next week
Originally we had planned on solar panels, condenser boiler, a back boiler stove, and rads throughout the house.
But are now looking into air to water heat pump with underfloor heating on the ground and first floor and rads in the converted attic space (2 bedrooms, a landing and a shower room)
The specs are, 405m2 (excluding converted attic).
The floors are insualted to 140mm.
The attic is insulated to 300mm
The external wall construction is as follows block 100mm with 150mm pumped bead cavity and block on flat on inside which is 225mm. There is no insulated board on the inside as we don't want to have plaster board walls.
There is thermal bridging around the windows and doors with insulated galvanised lentils.
The house will be air tight. Our windows are timber sliding sash, double glazed and argon filled with a U value of 1.0 W/m2K.

Our Engineer has given us a proposed BER of B1 based on the above specs.

In recent weeks we have been looking into air to water heat pumps and also GSHP. I would love any advice that anyone has on these. If we were to go down the heat pump route we would be doing UFH, no solar panels and no back boiler on the stove.

The main reason we want to go down the heat pump route is to reduce the cost of heating the house.

The more I read about them the more confused I get. It looks at the moment like the GSHP is too cost prohibitive for us the the only real option is the air to water heat pump.

The concerns I have are as follows
* The humidity in Ireland causing the pump to ice up and the energy cost of deicing the pump.
* High electricity costs
* Will the initial increased installation cost of the heat pump and UFH combined with the electricity bill actually make a real saving versus a condenser oil burner and oil.
* life span of the unit.
* Due to the size of the heat pump we need we have read that we would require 3 phase electricity. We are building in a very rural area, miles away from any town and are unsure if 3 phase electricity is even available to us. If it were available to us, the instillation cost to ESB is more at the time but how much would you save in running costs with 3 phase electricity?

Any advice is much appreciated

sheff the ref

As a matter of interest, why did you opt for block on the flat inside?

You may need to consider an alternative source of heating for occasions where the Heatpump breaks down, and you have to wait a few days for someone to check it out, electricity is off etc.

maysville

Sheff the ref, we opted for the block on the flat on the inside because of the style of the house. We're building a traditional country style house and we want to panel the inside of the windows to give a shutter effect and have the deep wall look. A bonus is that blocks also retain heat so should help with insulation.

We've now done a good bit of research and are going off the idea of air to water heat pump and now considering a ground source heat pump. We're meeting with the Engineer tomorrow and a few plumbers who specialise in heat pumps over the next few days. The main questions that we have at present with the ground source heat pump are as follows:

* Ground source heat pumps work best with underfloor heating and they are heating to a lower constant temperature that oil etc. We will have underfloor heating on the ground and first floor (405 sq/m). The converted attic area is approx 65 sq/m and this will be rads as we've no concrete floor between ground and first floor.
* Are we better to have an alternative source to heat hot water such as solar panels as the cost of using the heat pump to heat hot water might mean very high running costs.
* Can we use solar panels just to heat hot water and not for heating the house?
*Will solar panels be sufficient alone to heat water or will the GSHP have to do some of the work?
* Will we need the same volume of solar panels just to heat hot water as we had speced originally with oil. We had speced 6 sq/m of evacuated tube with a 300ltr solar cylinder.

BryanF

maysville wrote: »

Sheff the ref, we opted for the block on the flat on the inside because of the style of the house. We're building a traditional country style house and we want to panel the inside of the windows to give a shutter effect and have the deep wall look. A bonus is that blocks also retain heat so should help with insulation.

400MSQ! forget the 215 block internally if its only for your 'country style' windows and the thermal mass will be fine with 100mm block. (feel free to find me evidence to counter this statement)

what i would do with your walls in your 'oldie worldly, mock country, McManson' is try to keep the heat in by widening the cavity to 250mm instead of 150mm

may i politely ask, who is designing this monstrosity for you, perhaps do you have 10 kids and grandparents living with you? regardless of your footprint at this size you may well be looking at a pretty big heat pump! think of it like this - knock 10msq of your footprint and you've more than paid for your heat pump

you'll note that the BER B1 is easier to achieve the larger the house - for your own interest ask your assessor to reduce the footprint to 200msq and see what the rating is

i wish you all the best for your build and hope your designers are more meticulous about the air-tightness & thermal bridge detailing than they were about about the footprint

maysville

Thanks for that Brian but with all due respect I didn't ask advice re 'oldie wordly, mock country, McManson'. As you so politely asked 'this monstrosity' was designed by an architect, a building contractor is building it and an engineer to overseeing the build. I'm not willing to get into a debate about our choice of house, simply it's right for us and our family. I was asking about heat pump advice....

BryanF

maysville wrote: »

I'm not willing to get into a debate about our choice of house, simply it's right for us and our family. I was asking about heat pump advice....

fare point
its just you stated that

maysville wrote: »

The main reason we want to go down the heat pump route is to reduce the cost of heating the house.

dont you think that your fabric type and footprint impact the cost of your heating?

It looks at the moment like the GSHP is too cost prohibitive for us the the only real option is the air to water heat pump.

dont you think that by reducing by the footprint by say 10msq, you could afford the GSHP?

The concerns I have are as follows
* The humidity in Ireland causing the pump to ice up and the energy cost of deicing the pump.

a problem with cheaper products

* High electricity costs

dependent on the product, its install and your homes heat demand, but you haven't mentioned the figure for your demand

* Will the initial increased installation cost of the heat pump and UFH combined with the electricity bill actually make a real saving versus a condenser oil burner and oil.

over what time frame, what borrowing cost, what increase in oil/ elec costs ,what heating demand, what initial investment

* life span of the unit.

product / COP? & what are the maintenance costs

* Due to the size of the heat pump we need we have read that we would require 3 phase electricity. We are building in a very rural area, miles away from any town and are unsure if 3 phase electricity is even available to us. If it were available to us, the instillation cost to ESB is more at the time but how much would you save in running costs with 3 phase electricity?

and we're back to the bigger system required due to the footprint, do you see where I'm coming from? can you reduce the heating demand by improving the fabric insulation thus reduce the size of the heat pump to a standard phase supply?

maybe just give the viewers the demand loads & heat pump suggested by your advisers?

maysville

BryanF please see my post above about the GSHP

BryanF

maysville wrote: »

1. Are we better to have an alternative source to heat hot water such as solar panels as the cost of using the heat pump to heat hot water might mean very high running costs.
2. Can we use solar panels just to heat hot water and not for heating the house?
3. Will solar panels be sufficient alone to heat water or will the GSHP have to do some of the work?
4. Will we need the same volume of solar panels just to heat hot water as we had speced originally with oil.

1. no, its better to have one system well designed - you know my views on heat pump costs: its down to your footprint and fabric to keep demand low - have you considered gasification boiler and thermal store?
2. yes for summer and maybe spring autumn but not for winter
3. GSHP will do some work
4. ?

maysville

Our main aim with the house is to make it as energy efficient as possible. Yes it it a large house and this alone poses problems with choosing a heating system and the running costs of it.
We are trying to minimise as much heat loss as possible with good insulation, thermal bridging and air tightness.
We are just trying to make the correct decision with regards to the heating system to ensure the house is comfortably heated and our running costs are reasonable. I do understand that as the house is large our running costs are going to be larger than a smaller house.
We are willing to go down the route of GSHP as long as it's not too cost prohibitive and we're not going to have massive ESB bills afterwards.
We did look into wood gasification boilers and well as oat fed boilers and wood pellets. We would prefer not to go with these options as they are pretty labour intensive, we have no access to woodland so we'd have to source the wood, chop in, dry it. Have a large storage area to ensure the wood stays dry. The heat depends on the quality and dryness of the wood. You also can't heat the house if you're away for a few weeks as you need someone to reload the boiler.

sheff the ref

maysville wrote: »

Sheff the ref, we opted for the block on the flat on the inside because of the style of the house. We're building a traditional country style house and we want to panel the inside of the windows to give a shutter effect and have the deep wall look. A bonus is that blocks also retain heat so should help with insulation.

We've now done a good bit of research and are going off the idea of air to water heat pump and now considering a ground source heat pump. We're meeting with the Engineer tomorrow and a few plumbers who specialise in heat pumps over the next few days. The main questions that we have at present with the ground source heat pump are as follows:

* Ground source heat pumps work best with underfloor heating and they are heating to a lower constant temperature that oil etc. We will have underfloor heating on the ground and first floor (405 sq/m). The converted attic area is approx 65 sq/m and this will be rads as we've no concrete floor between ground and first floor.
* Are we better to have an alternative source to heat hot water such as solar panels as the cost of using the heat pump to heat hot water might mean very high running costs.
* Can we use solar panels just to heat hot water and not for heating the house?
*Will solar panels be sufficient alone to heat water or will the GSHP have to do some of the work?
* Will we need the same volume of solar panels just to heat hot water as we had speced originally with oil. We had speced 6 sq/m of evacuated tube with a 300ltr solar cylinder.

I wont get involved in pro's and con's of your house choice!! Your house, your choice

1.Most companies will spec the heatpump to also include heating the hot water and it makes sense because the heatpump will be running anyway. If the hot water tank has no heat requirement, the stat on the tank will relay that back anyway so there is no wasted electricity. I would suggest that heating hot water using the heatpump is the most efficient way of doing it. For a house of your size, particularly if the number of people in the house is small, then the hot water requirement will not amount to a huge proportion of the overall heating costs for the house. I have figures somewhere on the hot water percentage vs the overall heating requirement but cannot find them now.

2.You can use solar for Hot Water only. A dual coil cylinder will take care of that.

3.You will need the GSHP in winter time if there is not much sun. However on freezing cold but sunny days, the response from Solar is quite good I am told.

4.That is something to discuss with your engineer. Depends on how much hot water you want to generate really.

sheff the ref

maysville wrote: »

Our main aim with the house is to make it as energy efficient as possible. Yes it it a large house and this alone poses problems with choosing a heating system and the running costs of it.
We are trying to minimise as much heat loss as possible with good insulation, thermal bridging and air tightness.
We are just trying to make the correct decision with regards to the heating system to ensure the house is comfortably heated and our running costs are reasonable. I do understand that as the house is large our running costs are going to be larger than a smaller house.
We are willing to go down the route of GSHP as long as it's not too cost prohibitive and we're not going to have massive ESB bills afterwards.
We did look into wood gasification boilers and well as oat fed boilers and wood pellets. We would prefer not to go with these options as they are pretty labour intensive, we have no access to woodland so we'd have to source the wood, chop in, dry it. Have a large storage area to ensure the wood stays dry. The heat depends on the quality and dryness of the wood. You also can't heat the house if you're away for a few weeks as you need someone to reload the boiler.

Life is a rule of thumb.

The reality is that the cost of heating a house equates fully with the ability to retain heat in the house. Insulation, Air Tightness, Not leaving windows and doors open on frosty days.

With an underfloor heating system, you are not heating a house, you are retaining a level of heat in the house. The stats will call for heat, but if heat is not needed, then the heatpump will not be in use. Therefore insulation is more important than any heating system. If there is constant demand for heat, then the heatpump will run continuously.

Air to Water Heatpumps are under most pressure when the demand for heat is at its greatest in frosty weather. There are ways around this, such as a larger heatpump to compensate, or a supplementary heating system such as a back boiler stove. You have to factor in the weather in Ireland when making decisions. Will we get an extreme winter like late 2010 again? If we do, is it easier to have a stove rigged up which will provide some of the demand and take the pressure off the heatpump? Does the extra expense for a ground source heatpump make financial sense. If every winter was a 2010 winter, then yes, but if winters are predominantly mild, then it may not be worth the extra expense.

Everyone has to make their own choice. I would personally opt for boreholes rather than a standard ground source collector which can be more expensive again but that is for practical reasons rather than any fault with the system

afinador

Hi Maysville

no mention here about MHRV unit? Have you a target ACH figure for your build? I'd reiterate the importance of airtightness and insulation- as well as all the obvious design elements like point it South and keep Northern windows to a minimum...

I think if you get all that right your space heating requirement will be minimal, and the big question is hot water. As stated earlier, solar won't do this all year, so the heat pump is the best option- we're going air to water because the site's too tight for a bore, but all the figures point to it being an efficent, low cost way of giving a little space heat via low temp, large surface rads (2 for the entire 4 bed semi-d) and all the hot water needed

sheff the ref

The rule of thumb that was used when I was working in Geothermal a few years ago was a hot water requirement of 0.75Kw per person. That meant for a a 4 person house the overall requirement was 3Kw.

In terms of very approximate figures
A 2000 square foot house might have a space heating requirement of say 9Kw. Therefore the Hot Water requirement in theory would be 25% of the overall heat requirement of the house. So if say the 4000 square foot house had a space heating requirement of 18Kw, the Hot Water requirement would be somewhere around 15% of the overall heat requirement. However, the 0.75Kw was very generous. Let's say an electric shower is used in the house rather than a power shower, let's say that nobody ever takes a bath. The hot water requirement could be very minimal.

maysville

Thanks for all the replies, given me lots of food for thought. We got the provisional BER back from Engineer today and it's coming out at 53.16kWh/m2/yr which is an A3, not too far off an A2 and that is based on an 86% efficient condenser boiler. The one we have speced is a condenser boiler 35kw 96% efficient. It's also based on windows with a U value of 2, our windows have a U value of 1. So in fact the BER value if these were included would have come out better.
All our living space is facing east, south east, directly south and west. We have a lot of glass in this area, one room that faces South and West has two walls nearly made entirely of glass.

I have a few questions with regards to insulation, does the following appear sufficient especially the attic insulation? Do we need to improve on this or does it appear ok?

Floor 150mm insulation, this gives a U value of 0.21 W/m2K.
Walls: 150mm pumped bonded bead. Contacted the builder with regards to increasing the cavity to 250mm and removing the block on the flat on the inside as BryanF suggested. The block on the flat is necessary to support the weight of the hollow core breton floor slab. We also have internal walls that are block on the flat. Without these we would be looking at a lot of steel to replace the block on the flat. U value of walls is 0.25W/m2K.
Attic: 300mm acoustic insulation.

We have discussed the air to water heat pump briefly with a plumber today and the cost of the good quality ones he supplies (don't have name or COP value as I was only speaking to him briefly, we're meeting him tomorrow), these are the ones that don't have ice hanging off them all the time would be working out around the same as the GSHP.

It's looking at the moment like we might opt for GSHP and a stove with a back boiler, UFH on two floors and rads in attic and no solar panels.

The main concern about the GSHP is the fear of the unknown, you're really trusting the competency of the person installing it. I've read horror stories about people getting ESB bills of 2K for two months, only after they received the bill did they realise there was something wrong with the GSHP.

UFH. Again the fear of the unknown. I know people who have it installed with oil and the cost of running it constantly is very high and they're really unhappy with it. I know this isn't a problem with GSHP but again we're unfamiliar with it.

Condenser

maysville wrote: »

Thanks for all the replies, given me lots of food for thought. We got the provisional BER back from Engineer today and it's coming out at 53.16kWh/m2/yr which is an A3, not too far off an A2 and that is based on an 86% efficient condenser boiler. The one we have speced is a condenser boiler 35kw 96% efficient. It's also based on windows with a U value of 2, our windows have a U value of 1. So in fact the BER value if these were included would have come out better.
All our living space is facing east, south east, directly south and west. We have a lot of glass in this area, one room that faces South and West has two walls nearly made entirely of glass.

I have a few questions with regards to insulation, does the following appear sufficient especially the attic insulation? Do we need to improve on this or does it appear ok?

Floor 150mm insulation, this gives a U value of 0.21 W/m2K.
Walls: 150mm pumped bonded bead. Contacted the builder with regards to increasing the cavity to 250mm and removing the block on the flat on the inside as BryanF suggested. The block on the flat is necessary to support the weight of the hollow core breton floor slab. We also have internal walls that are block on the flat. Without these we would be looking at a lot of steel to replace the block on the flat. U value of walls is 0.25W/m2K.
Attic: 300mm acoustic insulation.

We have discussed the air to water heat pump briefly with a plumber today and the cost of the good quality ones he supplies (don't have name or COP value as I was only speaking to him briefly, we're meeting him tomorrow), these are the ones that don't have ice hanging off them all the time would be working out around the same as the GSHP.

It's looking at the moment like we might opt for GSHP and a stove with a back boiler, UFH on two floors and rads in attic and no solar panels.

The main concern about the GSHP is the fear of the unknown, you're really trusting the competency of the person installing it. I've read horror stories about people getting ESB bills of 2K for two months, only after they received the bill did they realise there was something wrong with the GSHP.

UFH. Again the fear of the unknown. I know people who have it installed with oil and the cost of running it constantly is very high and they're really unhappy with it. I know this isn't a problem with GSHP but again we're unfamiliar with it.

If your house is 400sqm and getting an a3 rating before a heatpump is taken into consideration then you don't need 3 phase. You don't even need that large a heatpump.

My advice would be not to use an air to water unit especially on a reasonably substantial house. A properly installed gshp will give far superior results and more consistent bills year in year out.

Get an experienced installer with a good track record to install. Heat pumps are the furthest end of the scale from oil and gas boilers when it comes to installation practices and control and need specialist knowledge in order to get the most out of them. They are generally not in the remit of your average plumber and in my opinion unless you can repair every facet of the system you shouldn't be installing them. Find out if your installer can change a compressor, fault find the electrics, troubleshoot the hydraulic side. If they can't you'll be left high and dry at some stage in the future.

froshtyv

maysville wrote: »

Thanks for all the replies, given me lots of food for thought. We got the provisional BER back from Engineer today and it's coming out at 53.16kWh/m2/yr which is an A3, not too far off an A2 and that is based on an 86% efficient condenser boiler. The one we have speced is a condenser boiler 35kw 96% efficient. It's also based on windows with a U value of 2, our windows have a U value of 1. So in fact the BER value if these were included would have come out better.
All our living space is facing east, south east, directly south and west. We have a lot of glass in this area, one room that faces South and West has two walls nearly made entirely of glass.

I have a few questions with regards to insulation, does the following appear sufficient especially the attic insulation? Do we need to improve on this or does it appear ok?

Floor 150mm insulation, this gives a U value of 0.21 W/m2K.
Walls: 150mm pumped bonded bead. Contacted the builder with regards to increasing the cavity to 250mm and removing the block on the flat on the inside as BryanF suggested. The block on the flat is necessary to support the weight of the hollow core breton floor slab. We also have internal walls that are block on the flat. Without these we would be looking at a lot of steel to replace the block on the flat. U value of walls is 0.25W/m2K.
Attic: 300mm acoustic insulation.

We have discussed the air to water heat pump briefly with a plumber today and the cost of the good quality ones he supplies (don't have name or COP value as I was only speaking to him briefly, we're meeting him tomorrow), these are the ones that don't have ice hanging off them all the time would be working out around the same as the GSHP.

It's looking at the moment like we might opt for GSHP and a stove with a back boiler, UFH on two floors and rads in attic and no solar panels.

The main concern about the GSHP is the fear of the unknown, you're really trusting the competency of the person installing it. I've read horror stories about people getting ESB bills of 2K for two months, only after they received the bill did they realise there was something wrong with the GSHP.

UFH. Again the fear of the unknown. I know people who have it installed with oil and the cost of running it constantly is very high and they're really unhappy with it. I know this isn't a problem with GSHP but again we're unfamiliar with it.

Have you discussed with your plumber how you would do that? One is a sealed system the other is an open vented?

Curious Geroge

Has anyone any experience with a mastertherm heat pump ? Recommended by my plumber but I've never heard of it.

Tommyboy08

Curious Geroge wrote: »

Has anyone any experience with a mastertherm heat pump ? Recommended by my plumber but I've never heard of it.

Worked on a few of them, both badly installed which wasn't the machines fault,
Controls were the poor point and on the heavy side when it came to electrical input, overall wery middle of the road heat pump and should be cheap to buy, but as with any heat pump its performance will only be as good as the installation and overall design of the system.

jamesf25

Building a new build in new year, 3000sqft block built dormer with hollow core. Going to have UHF with vertical bores. From talking to allot of different people horizontal pipes are supposed to be better for boggy wetter ground. If u have well drained land near Coast were about 10min from enniscrone beach so I was told vertical boar will be more effective! Interesting to see wat your opinions are?
We will also have a small stove with boiler backing up hot aster store only. 250mm of beads in wall and 250mm of spray foam in dormer attic

Also air to water units besides Coast line does salty air have any negative effect on units!?

My justification for geothermal and UHF was on price!
UHF with ego thermal = €17000
Oil boiler + rads + solar (10% green) = €13000 plus!!
Also oil increases every year!!

sheff the ref

Unfortunately salt will damage an air to water unit if you are that close to the coast. However you can install a ground source heat pump internally in a shed, sealed from the elements, so that eliminates any problem there.

I believe this boggy wetter ground theory is relevant but overstated. The pipes are sitting 1m below the ground where the temperature is relatively constant regardless of weather conditions most of the time (Winter 2010 may be an exception). Obviously this chilled antifreeze/water is sent out into the pipes to absorb the ambient ground temperatue. However, in situations of water movement in the ground in direct contact with the pipes, it creates better conductivity of temperature for want of a better word meaning the temperature change happens faster. However, that does not mean that on dry ground the pipes are that much less efficient. Picture a glass of iced water. It will melt on its own at room temperature, however if placed in a bowl of water at ambient temperature, it will happen quicker.

As regards borehole vs horizontal pipes, I think borehole is tidier as it requires less rooting and digging and obviously less space. A horizontal collector requires a lot of square metres

jamesf25 wrote: »

Building a new build in new year, 3000sqft block built dormer with hollow core. Going to have UHF with vertical bores. From talking to allot of different people horizontal pipes are supposed to be better for boggy wetter ground. If u have well drained land near Coast were about 10min from enniscrone beach so I was told vertical boar will be more effective! Interesting to see wat your opinions are?
We will also have a small stove with boiler backing up hot aster store only. 250mm of beads in wall and 250mm of spray foam in dormer attic

Also air to water units besides Coast line does salty air have any negative effect on units!?

My justification for geothermal and UHF was on price!
UHF with ego thermal = €17000
Oil boiler + rads + solar (10% green) = €13000 plus!!
Also oil increases every year!!

engineermike

Hi OP,
r/e ASHP - yes salinity does have effect & also causes plenty of headaches with service intervals on the compressor unit. Someone mentioned mounting it in an outbuilding but that depends on where that is located - and then you might be getting into further expense on 0 loss pipework (costly).

On the choice of vert / horizontal collector, site suitability really is the key there.
Personally I'd drag my engineer back to the drawing board on the choice of insulation type / material. There are better U values that can be achieved for what is a fixed cost - item, investment.
Furthermore air tightness again fixed cost. As other posters have mentioned aspect of windows (and choice of same) even finishing materials choice all going to have a bearing on how much electrical work you HP will be required to do.
If you don't get the fabric of the building to the highest spec within your budget- the pump can and will run away with your wallet.
Solar contribution for Hot water provision / contribution should still be a consideration in my mind as easy to tie it and the pump together - driving down that electrical work of the HP (somewhere around the degree of 30 - 40% over the year). Solar has come down in price also of late.

As for the stove with the back boiler- usually a no / no with a heat pump. Uncontrollable heat sources don't work well with HP's - except if system is designed with a heat exchange, and again extra expense.

Hope the above is useful, but seems like a lot of good advice on this thread as it stands
mike f

Tommyboy08

engineermike wrote: »

Solar contribution for Hot water provision / contribution should still be a consideration in my mind as easy to tie it and the pump together - driving down that electrical work of the HP (somewhere around the degree of 30 - 40% over the year). Solar has come down in price also of late.
f

Solar and heat pumps together does not make any financial sense,
The hot water demand of a house is on average 20% of the total running time of the heat pump per year, so about 25 to 30% of the total electric usage, so if we say that the solar panels satisfy all my hot water demands for six months of the year then I would have saved myself 15% of my running costs,
When you consider that a well designed properly installed heat pump system would heat a reasonable well insulated 3000sq/ft house for €500 then your only going to save €75 per year, it'll take a long time to payback the solar panels