Air to water heat pump for 35 y/o house

Jaymacc

We have a 35 y/o 3 bed bungalow and are taking out solid fuel range which had back boiler for water and rads. We have cavity walls pumped with insulation beads and a good depth insulation in the attic along with double glazed upvc windows and doors. Looking to install air to water heat pump system. Has anyone else who is in the same boat done this and how are you getting on with it? Your thoughts and experiences would be most appreciated.

Shefwedfan

Jaymacc wrote: »

We have a 35 y/o 3 bed bungalow and are taking out solid fuel range which had back boiler for water and rads. We have cavity walls pumped with insulation beads and a good depth insulation in the attic along with double glazed upvc windows and doors. Looking to install air to water heat pump system. Has anyone else who is in the same boat done this and how are you getting on with it? Your thoughts and experiences would be most appreciated.

Have you got anyone to size the A2W?



What sort of radiators do you have.

Jaymacc

Shefwedfan wrote: »

Have you got anyone to size the A2W?



What sort of radiators do you have.

No nobody in yet. We just have the normal rads which were put in for the solid fuel range pumped system.

Shefwedfan

Jaymacc wrote: »

No nobody in yet. We just have the normal rads which were put in for the solid fuel range pumped system.

First off, don’t mind the grant....you will probably have to pay 5k to “upgrade” the house to get the 3k grant

A few people have done.....I’m currently looking and doing lots of research....I’m a bit bigger, 3000 sq ft bungalow. All the work you have done plus a few more....60% new rads

So phase 1 I am going to install a MagnaClean, clear some of the s**t out of system. I was recommended it and looks great, buying tomor

Phase 2, potentially I might try and remove the electric showers and replace with power showers. This is recommendation from one guy, this is because of the power requirements in house....

Phase 3 A2W, at the moment I am looking at monoblock system as it seems easiest to install. Panasonic look good, they also do a HT version which I think you will need. The HT runs at higher temp for retro fit....

Other option in my house is leave current boiler as a backup, some companies do that, so if the A2W can’t get to temp the boiler will kick in....they also offer an electric add on to also kick up the temp but I would guess hard on electricity

famagusta

Air tightness is one of the most important things with the heat pump, you need that sorted

TomOnBoard

famagusta wrote: »

Air tightness is one of the most important things with the heat pump, you need that sorted

+++1000

I checked this out for my house built in 1980.

My heating guy felt it's only economical when outside air temps are above 4 or 5 C. Below that, and it's costing a lot more to extract heat from the air. At zero and below, it's gonna be a struggle in my gaff without a significant retrofit, incl. all my rads would all need replacing.

Jaymacc

Shefwedfan wrote: »

First off, don’t mind the grant....you will probably have to pay 5k to “upgrade” the house to get the 3k grant

A few people have done.....I’m currently looking and doing lots of research....I’m a bit bigger, 3000 sq ft bungalow. All the work you have done plus a few more....60% new rads

So phase 1 I am going to install a MagnaClean, clear some of the s**t out of system. I was recommended it and looks great, buying tomor

Phase 2, potentially I might try and remove the electric showers and replace with power showers. This is recommendation from one guy, this is because of the power requirements in house....

Phase 3 A2W, at the moment I am looking at monoblock system as it seems easiest to install. Panasonic look good, they also do a HT version which I think you will need. The HT runs at higher temp for retro fit....

Other option in my house is leave current boiler as a backup, some companies do that, so if the A2W can’t get to temp the boiler will kick in....they also offer an electric add on to also kick up the temp but I would guess hard on electricity

Cheers for info. You seem to be very knowledgable on it.

What rads did you get?

Magaclean sounds good. Let me know how you get on with it.

Make sure you get a good pump for power showers. We have one and it is super powerful.

Why did you settle on Panasonic? Have you looked at Mitsubishi?

Great idea to leave the boiler set up. We would too if we had oil but we have solid fuel range!

Jaymacc

famagusta wrote: »

Air tightness is one of the most important things with the heat pump, you need that sorted

What would be best way to achieve this then? Any wish list?!

Shefwedfan

Jaymacc wrote: »

What would be best way to achieve this then? Any wish list?!

Airtighness is hard to achieve on existing property, I replastered huge section of house and put the air tightness tape on then

Potentially I think foam insulation in attic helps. More people on here know

Small things like : stoves instead of open fires, draft lobby, etc will help.

Jaymacc

Shefwedfan wrote: »

Airtighness is hard to achieve on existing property, I replastered huge section of house and put the air tightness tape on then

Potentially I think foam insulation in attic helps. More people on here know

Small things like : stoves instead of open fires, draft lobby, etc will help.

Thanks. Was replastering a lot of work? Costly I bet! What type of windows have you?

Have you gone with the Air to Water now?

gooseygander

Jaymacc wrote: »

We have a 35 y/o 3 bed bungalow and are taking out solid fuel range which had back boiler for water and rads. We have cavity walls pumped with insulation beads and a good depth insulation in the attic along with double glazed upvc windows and doors. Looking to install air to water heat pump system. Has anyone else who is in the same boat done this and how are you getting on with it? Your thoughts and experiences would be most appreciated.

Have you vents in your walls ?, air to water systems work best with a mhrv system and not the best idea when you have 4 to 6 inch holes to the outside in most rooms. In my opinion this is a major factor to consider.

Jaymacc

gooseygander wrote: »

Have you vents in your walls ?, air to water systems work best with a mhrv system and not the best idea when you have 4 to 6 inch holes to the outside in most rooms. In my opinion this is a major factor to consider.

Yes there were two vents but they are blocked up now. What is mhrv? I think the HT pumps sound like a good option. Need to get an energy advisor in. Anyone know someone in Galway who is registered with SEAI? DM me please!

Jaymacc

Jaymacc wrote: »

Yes there were two vents but they are blocked up now. What is mhrv? I think the HT pumps sound like a good option. Need to get an energy advisor in. Anyone know someone in Galway who is registered with SEAI? DM me please!

Googled mhrv. Yes we are looking at that. Is the air that is replaced heated or cold?

gooseygander

Jaymacc wrote: »

Googled mhrv. Yes we are looking at that. Is the air that is replaced heated or cold?

Stale warm air being removed from the house has its heat removed by the cold fresh air coming in. It’s not hot air that reaches the rooms but it’s not as cold as outside, if you get my drift. Also you should never, never block vents if your house is not ventilated by another source. This is a major no no and asking for trouble.

Jaymacc

gooseygander wrote: »

Stale warm air being removed from the house has its heat removed by the cold fresh air coming in. It’s not hot air that reaches the rooms but it’s not as cold as outside, if you get my drift. Also you should never, never block vents if your house is not ventilated by another source. This is a major no no and asking for trouble.

I get you. Windows are opened during the days so it is well ventilated.

Shefwedfan

Jaymacc wrote: »

Thanks. Was replastering a lot of work? Costly I bet! What type of windows have you?

Have you gone with the Air to Water now?

I had water leaks, lots of them which brought dry rot and wet rot. The house had sat for 2 years with water flowing into the concrete. Not a great job

So I dug up the floors and stripped about 60-70% of the house down to the blocks. Then I:

Installed new plumbing with insulation on the pipe,New radiators
New floors with insulation,Insulated slabs on exterior walls and on ceiling(house had high ceiling so it did not affect room height),Air tightness on the windows,Draft lobby in hallwith triple glazing,Large sliding triple glazed door to block off the sun room, topped up the attics with insulation


The house had renovations done in 2006 and had new windows etc so no need to replace. In the 2006 renovation the plumber was f**king useless, loads of leaks. I didn't own at that time.

So now I have oil boiler, which is oversized for house because it was put in when the house was poorly insulated. I also have a solid fuel stove which is connected to the heating but it is on its last legs so needs to be replaced.

I have not gone A2W yet but that is plan. I have done a lot of research and my 3 brothers have installed but on new builds so they done underfloor.

I would like on one section of the house to spray foam the attic and see the performance. The house is broke up into section with seperate roof space so I could in reality do one section and then see if it will outperform the larger section which has attic insulation.

I have talked to 2 companies. Panasonic and Unipipe. Unipipe are selling the NIBE system which will use the boiler as back up. Panasonic can do that as well but run the HT system which I think is a better option for the radiators. Also Panasonic is the Monoblock which is an easier installation. Potentially just hook out stove connections and connect in A2W

Bit of a ramble I know but that is what is going on in the noggin at the moment. The current boiler is working perfect so I don't have gun to my head which is a positive. I would like to move in that direction sooner rather than later......

Shefwedfan

Final post. So the grant. You can't just apply. You need to go to company to do a review, not sure how much they will charge but
They will check insulation levels, windows and doors etc

If they are not up to standard then you have to replace
Radiators will be sized for hot water, especially if older radiators so they will ask you to replace all of them with larger ones or aluminum.

By the time you do all that you will have wasted your time getting the grant. Especially windows and doors. They could be perfect but not the exact u value they require so you have to replace.

You could try running you current system at a lower temp. Can it tick over at 45 degree or so and leave it running all day. See if it actually keeps the house warm. It is probably heating the water to 80 or something, the idea is to turn it down and see what happens?

I would try clean it out before air to water, so empty water out of system. Install MagnaClean with new water and let it run for a few weeks. That will help it alot. I would like to do the following but I doubt many Irish plumbers have this system : https://www.youtube.com/watch?v=xG2aPuN3wg8

Latro

famagusta wrote: »

Air tightness is one of the most important things with the heat pump, you need that sorted

Why would it be more important with one heating system and less with other?


If you lose 100kWh heat energy per day does it really matter how you compensate that?


Does 100kWh worth of heat produced by oil feel different from 100kWh of heat produced by gas, electricity or anything else?

ArrBee

gooseygander wrote: »

Stale warm air being removed from the house has its heat removed by the cold fresh air coming in. It’s not hot air that reaches the rooms but it’s not as cold as outside, if you get my drift. Also you should never, never block vents if your house is not ventilated by another source. This is a major no no and asking for trouble.

surely a 35 yo house as plenty of "other sources" of ventilation.
I know our 10yo house has drafts everywhere....

Dardania

The air tightness matters less with gas or oil compared to heat pump because of the sheer overcapacity of those boilers.

Oil or gas can throw out massive amounts of heat in short periods of time to overcome air tightness issues, and how you operate them is basically like a saw tooth wave, where the internal temperate fluctuates up and down semi-dramatically. Picture a car going up a hill on a motorway, where it is overtaking people - that's what the gas boiler is intended to do. Loads of spare capacity, and it doesn't like to output low amounts of heat. It works well with house that lose heat fast (due to low insulation and high air permeability)

By contrast, a heat pump setup works best when it is on 24/7, trying to maintain the home at a constant temperature. It does not have a load of spare capacity to heat up from a low temperature in 30 minutes. It needs a smooth & level road, and it'll chug along like a train. So less heat loss is a pre-requisite. A heat pump could put out 3kW of heat very effectively and far more cheaply compared to the gas boiler, which wants to throw out between 8kW - 24kW of heat in bursts of energy.

If OP's house was fully insulated (doesn't sound like they're far off) and fully air tight, they'd notice with a gas boiler that it wouldn't stay lit for extended periods of time, as it isn't losing heat fast enough.

Shefwedfan

Dardania wrote: »

The air tightness matters less with gas or oil compared to heat pump because of the sheer overcapacity of those boilers.

Oil or gas can throw out massive amounts of heat in short periods of time to overcome air tightness issues, and how you operate them is basically like a saw tooth wave, where the internal temperate fluctuates up and down semi-dramatically. Picture a car going up a hill on a motorway, where it is overtaking people - that's what the gas boiler is intended to do. Loads of spare capacity, and it doesn't like to output low amounts of heat. It works well with house that lose heat fast (due to low insulation and high air permeability)

By contrast, a heat pump setup works best when it is on 24/7, trying to maintain the home at a constant temperature. It does not have a load of spare capacity to heat up from a low temperature in 30 minutes. It needs a smooth & level road, and it'll chug along like a train. So less heat loss is a pre-requisite. A heat pump could put out 3kW of heat very effectively and far more cheaply compared to the gas boiler, which wants to throw out between 8kW - 24kW of heat in bursts of energy.

If OP's house was fully insulated (doesn't sound like they're far off) and fully air tight, they'd notice with a gas boiler that it wouldn't stay lit for extended periods of time, as it isn't losing heat fast enough.

Correct but some people do go overboard with this. As mentioned above if you have the ability to turn the current boiler down to a lower temp and let run for a long period it can give you a very good insight....


Also less scientific. Heat up the house and see how long it gets to go cold again. If it doesn't take long then heat loss is high. If the house holds the heat then you are looking better

Jaymacc

Shefwedfan wrote: »

Final post. So the grant. You can't just apply. You need to go to company to do a review, not sure how much they will charge but
They will check insulation levels, windows and doors etc

If they are not up to standard then you have to replace
Radiators will be sized for hot water, especially if older radiators so they will ask you to replace all of them with larger ones or aluminum.

By the time you do all that you will have wasted your time getting the grant. Especially windows and doors. They could be perfect but not the exact u value they require so you have to replace.

You could try running you current system at a lower temp. Can it tick over at 45 degree or so and leave it running all day. See if it actually keeps the house warm. It is probably heating the water to 80 or something, the idea is to turn it down and see what happens?

I would try clean it out before air to water, so empty water out of system. Install MagnaClean with new water and let it run for a few weeks. That will help it alot. I would like to do the following but I doubt many Irish plumbers have this system : https://www.youtube.com/watch?v=xG2aPuN3wg8

Got quote for 450 euro to come out and advise on what if anything needs doing before we go with air to water. As you said it might be costly getting all those things done just for the grant but maybe they need doing if the system is to work well.

Solid Fuel system here so no way to regulate the heat or turn it down!

The Magnaclean sounds great and would be a good way to go. Might give it a try!

Jaymacc

Shefwedfan wrote: »

I had water leaks, lots of them which brought dry rot and wet rot. The house had sat for 2 years with water flowing into the concrete. Not a great job

So I dug up the floors and stripped about 60-70% of the house down to the blocks. Then I:

Installed new plumbing with insulation on the pipe,New radiators
New floors with insulation,Insulated slabs on exterior walls and on ceiling(house had high ceiling so it did not affect room height),Air tightness on the windows,Draft lobby in hallwith triple glazing,Large sliding triple glazed door to block off the sun room, topped up the attics with insulation


The house had renovations done in 2006 and had new windows etc so no need to replace. In the 2006 renovation the plumber was f**king useless, loads of leaks. I didn't own at that time.

So now I have oil boiler, which is oversized for house because it was put in when the house was poorly insulated. I also have a solid fuel stove which is connected to the heating but it is on its last legs so needs to be replaced.

I have not gone A2W yet but that is plan. I have done a lot of research and my 3 brothers have installed but on new builds so they done underfloor.

I would like on one section of the house to spray foam the attic and see the performance. The house is broke up into section with seperate roof space so I could in reality do one section and then see if it will outperform the larger section which has attic insulation.

I have talked to 2 companies. Panasonic and Unipipe. Unipipe are selling the NIBE system which will use the boiler as back up. Panasonic can do that as well but run the HT system which I think is a better option for the radiators. Also Panasonic is the Monoblock which is an easier installation. Potentially just hook out stove connections and connect in A2W

Bit of a ramble I know but that is what is going on in the noggin at the moment. The current boiler is working perfect so I don't have gun to my head which is a positive. I would like to move in that direction sooner rather than later......

Fair play. You have a lot of groundwork done.

I am doing other renovations and just wish the heating system would be easier to decide on. I think the HT option might be best for us as we have large double glazed windows which probably let heat out.

I think SEAI need to offer more incentives to us with older homes to upgrade them without having to be paying 'advisory' fees. I have heard of people paying these Advisors and being left in cold homes as the advice was not correct!

Jaymacc

ArrBee wrote: »

surely a 35 yo house as plenty of "other sources" of ventilation.
I know our 10yo house has drafts everywhere....

Yeah but they seem to want zero drafts with air to water systems. Expensive controlled drafts seems to be the way!

Jaymacc

Dardania wrote: »

The air tightness matters less with gas or oil compared to heat pump because of the sheer overcapacity of those boilers.

Oil or gas can throw out massive amounts of heat in short periods of time to overcome air tightness issues, and how you operate them is basically like a saw tooth wave, where the internal temperate fluctuates up and down semi-dramatically. Picture a car going up a hill on a motorway, where it is overtaking people - that's what the gas boiler is intended to do. Loads of spare capacity, and it doesn't like to output low amounts of heat. It works well with house that lose heat fast (due to low insulation and high air permeability)

By contrast, a heat pump setup works best when it is on 24/7, trying to maintain the home at a constant temperature. It does not have a load of spare capacity to heat up from a low temperature in 30 minutes. It needs a smooth & level road, and it'll chug along like a train. So less heat loss is a pre-requisite. A heat pump could put out 3kW of heat very effectively and far more cheaply compared to the gas boiler, which wants to throw out between 8kW - 24kW of heat in bursts of energy.

If OP's house was fully insulated (doesn't sound like they're far off) and fully air tight, they'd notice with a gas boiler that it wouldn't stay lit for extended periods of time, as it isn't losing heat fast enough.

You sound like you know a lot about this stuff.

What about a HT air to water system. Do you think it would suit us or do you think a gas boiler is the way to go?

Shefwedfan

Jaymacc wrote: »

You sound like you know a lot about this stuff.

What about a HT air to water system. Do you think it would suit us or do you think a gas boiler is the way to go?

Have you contacted any of the companies to see what sized A2W you need?


Do you have gas that is connected to your house?



How old is the radiators in the house? is the pipes insulated?



Do you have a place to install the A2W which will easily connect into existing system?

Dardania

Jaymacc wrote: »

You sound like you know a lot about this stuff.

What about a HT air to water system. Do you think it would suit us or do you think a gas boiler is the way to go?

Not a huge knowledge in A2W specifically, but I have experience in specifying heating systems for commercial premises, and a general knowledge of system sizing from industrial projects. I am also considering A2W for my own well insulated home so my story is similar to yours. For What it's worth, I live in a country at the moment temporarily where the heating is by district heating, and each radiator is sized to only have a minor amount of spare capacity to heat up from cold. We find that when we come back from holidays and turn the radiators on that it's a day or so before the apartment is warm enough again, so I have some personal experience there with heating systems that want to be consistently run 24/7.

My opinion is that we should all look at some sort of electric heating - there are reasons why:

- climate change - gas & oil are the way of the dinosaurs and while it's nice to think ecologically, I suspect the carbon tax is gradually going to increase to a high level over the next 10 years. Who wants to pay that tax?!
- Having 1 bill rather than 2 (so elec & gas) is cheaper when you think of standing charge. Or if thinking of oil, the cost of delivery
- heat pumps deliver a consistent heat 24/7 which is very comfortable in a house. As I said, I live somewhere that heat is on all the time - it's a bit weird to visit relatives in Ireland and see them having to stoke the fire at different times of the day.

and in your case the pros of A2W are more solid:
- you have a relatively well insulated house which is one of the prerequisites
- the fact that you need to open windows during the day in the house would seem to suggest that you house is relatively airtight - another prerequisite met
- you don't have to write off the cost of a relatively recent heating system - you're scrapping an ancient solution so why not go for the best in class at the moment?

There are potential issues for you, such as you might end up needing to fit a MHRV system (remember that A2W doesn't have a huge overcapacity to heat spaces back up quickly after closing the windows) but that can be beneficial for internal comfort. Also, you're in a bungalow, so it's relatively simple to fit compared to a 2 storey or more structure.

Check out: https://www.seai.ie/grants/home-energy-grants/heat-pump-systems/

Shefwedfan

I agree with all of the above Dardania. Oil is going to go one way. You can guess which way. Even if the price of oil reduces the government are going to have to start to increase carbon tax.

I have 3 brother who have installed geothermal , none have yet had to invest in MHRV system. Now the house was built for the geothermal and uses under floor heating but they have no major issues. They have 2-3 story house so a larger job

Personally in my own house the plan would be to install long-term to my house is bungalow so a lot easier to install. But that could be in 10 years.

I have an oil boiler which is perfect and works. So the move to A2W is more strategic than reactive.

As posted above the SEAI grant, especially for retrofit, seems to be a bit of a waste of time. After talking to people about this, you pay for someone to do a review, based on above 450, they then give you a list of upgrades you need to do. Which normally cost more than the grant. So you have wasted 450 of your A2W heat pump budget

Unless you are fairly certain you have top of the range windows and doors as a start I would not bother getting anyone in. Also they will size all the radiators and you have to replace each radiator which is too small....

Jaymacc

Shefwedfan wrote: »

Have you contacted any of the companies to see what sized A2W you need?


Do you have gas that is connected to your house?



How old is the radiators in the house? is the pipes insulated?



Do you have a place to install the A2W which will easily connect into existing system?

Hi. The quote I got was for a Mitsubishi Ecodan Heat Pump (9kw 7/35) and they will replace rads so there will be 13 new aluminium ones included.

We dont have gas connected and are in rural Ireland so would have to get that set up if we went with gas. Is it good?

The rads are about 20 years old and I doubt they pipes are insulated. They are under concrete floors so hard to tell.

The a2w system will fit in kitchen where we have the hot press as it would replace the hot tank we have at present.

Jaymacc

Dardania wrote: »

Not a huge knowledge in A2W specifically, but I have experience in specifying heating systems for commercial premises, and a general knowledge of system sizing from industrial projects. I am also considering A2W for my own well insulated home so my story is similar to yours. For What it's worth, I live in a country at the moment temporarily where the heating is by district heating, and each radiator is sized to only have a minor amount of spare capacity to heat up from cold. We find that when we come back from holidays and turn the radiators on that it's a day or so before the apartment is warm enough again, so I have some personal experience there with heating systems that want to be consistently run 24/7.

My opinion is that we should all look at some sort of electric heating - there are reasons why:

- climate change - gas & oil are the way of the dinosaurs and while it's nice to think ecologically, I suspect the carbon tax is gradually going to increase to a high level over the next 10 years. Who wants to pay that tax?!
- Having 1 bill rather than 2 (so elec & gas) is cheaper when you think of standing charge. Or if thinking of oil, the cost of delivery
- heat pumps deliver a consistent heat 24/7 which is very comfortable in a house. As I said, I live somewhere that heat is on all the time - it's a bit weird to visit relatives in Ireland and see them having to stoke the fire at different times of the day.

and in your case the pros of A2W are more solid:
- you have a relatively well insulated house which is one of the prerequisites
- the fact that you need to open windows during the day in the house would seem to suggest that you house is relatively airtight - another prerequisite met
- you don't have to write off the cost of a relatively recent heating system - you're scrapping an ancient solution so why not go for the best in class at the moment?

There are potential issues for you, such as you might end up needing to fit a MHRV system (remember that A2W doesn't have a huge overcapacity to heat spaces back up quickly after closing the windows) but that can be beneficial for internal comfort. Also, you're in a bungalow, so it's relatively simple to fit compared to a 2 storey or more structure.

Check out: https://www.seai.ie/grants/home-energy-grants/heat-pump-systems/

Thanks for all the info. I think we will go with a heat pump but I fear we will get it and it won’t be as warm as we are used to and we will have to go digging up pipes to insulate them, changing windows from double to triple glazing, dry lining exernal walls, spray foaming the attic, putting in front porch like many here are suggesting.

Do you think the HT Heat Pumps would be worth while? What brand is best for them?

Dardania

I have had a look at the SEAI's spec, and to be fair it's quite reasonable. In fact they seem to be pretty easy going on topics like heating controls, compared to what they require for the heating controls upgrade to a gas boiler...

https://www.seai.ie/resources/publications/Code-of-practice-technical-Specification.pdf

See chapter 7.9.

The only real difficult bit there that I can see is that the heat loss must be below 2W/K/m2 of floor area. That is what might drive fabric upgrades (like better insulation or ventilation)
It appears that the DEAP software (which generates BER certificates) has an output for this. So, maybe even as simple as getting a BER cert done would be a way to see if the building fabric is suitable to install A2W using SEAI grant...and indeed feasible in any sense of the word. That would give you a good steer as to whether heat pump will prevent you from feeling cool.
I must email the chap that did my BER after I got my last SEAI grant for insulation, to see if my house complies as it is...

Jaymacc

Shefwedfan wrote: »

I agree with all of the above Dardania. Oil is going to go one way. You can guess which way. Even if the price of oil reduces the government are going to have to start to increase carbon tax.

I have 3 brother who have installed geothermal , none have yet had to invest in MHRV system. Now the house was built for the geothermal and uses under floor heating but they have no major issues. They have 2-3 story house so a larger job

Personally in my own house the plan would be to install long-term to my house is bungalow so a lot easier to install. But that could be in 10 years.

I have an oil boiler which is perfect and works. So the move to A2W is more strategic than reactive.

As posted above the SEAI grant, especially for retrofit, seems to be a bit of a waste of time. After talking to people about this, you pay for someone to do a review, based on above 450, they then give you a list of upgrades you need to do. Which normally cost more than the grant. So you have wasted 450 of your A2W heat pump budget

Unless you are fairly certain you have top of the range windows and doors as a start I would not bother getting anyone in. Also they will size all the radiators and you have to replace each radiator which is too small....

When you talk about windows. Are upvc double glazed windows which are about 7 years old ok for use with a2w system?

Also, are you saying they reduce size of the rads in each room? Why would they do that when the temp pumped around is lower with a2w?

Jaymacc

Dardania wrote: »

I have had a look at the SEAI's spec, and to be fair it's quite reasonable. In fact they seem to be pretty easy going on topics like heating controls, compared to what they require for the heating controls upgrade to a gas boiler...

https://www.seai.ie/resources/publications/Code-of-practice-technical-Specification.pdf

See chapter 7.9.

The only real difficult bit there that I can see is that the heat loss must be below 2W/K/m2 of floor area. That is what might drive fabric upgrades (like better insulation or ventilation)
It appears that the DEAP software (which generates BER certificates) has an output for this. So, maybe even as simple as getting a BER cert done would be a way to see if the building fabric is suitable to install A2W using SEAI grant...and indeed feasible in any sense of the word. That would give you a good steer as to whether heat pump will prevent you from feeling cool.
I must email the chap that did my BER after I got my last SEAI grant for insulation, to see if my house complies as it is...

Great. I will try dig out our cert too and see what it says. What part will I need to look at on it to see if we are good enough for A2W?

Dardania

Jaymacc wrote: »

Great. I will try dig out our cert too and see what it says. What part will I need to look at on it to see if we are good enough for A2W?

It doesn't say it directly. You would need to speak to the assessor who generated it - they need to look at a parameter in the software they used to generate the certificate.
If you have the cert, it should have a BER number on it. If you put the BER number into this website
https://ndber.seai.ie/pass/ber/search.aspx
it should give you the contact details of the BER assessor. They can find the number thus:

The minimum requirement is based on the total heat loss for the dwelling, which includes the fabric and ventilation heat loss. The Heat Loss Indicator, HLI, is calculated by the DEAP software, specified as the “Total Heat Loss per m2”. It is found in DEAP 3 in the Building Elements section, Heat Loss results tab, specified as the Total Heat Loss per m2. In DEAP 4 it will be located in “View Assessment – Building – Heat Loss (Building Fabric)”.

Maybe the assessor will give you this number gratis if you ask nicely / agree to come back to them post the works, as you need an updated BER cert to successfully avail of the grant. And either way, this number should give you a feel for how effective the A2W would be - it doesn't mean you have to go via the grant system if the financials don't stack up (to shefwed's point) however I would recommend it, as it ensures a minimum installation quality will be most likely be achieved.

Shefwedfan

Jaymacc wrote: »

Hi. The quote I got was for a Mitsubishi Ecodan Heat Pump (9kw 7/35) and they will replace rads so there will be 13 new aluminium ones included.

We dont have gas connected and are in rural Ireland so would have to get that set up if we went with gas. Is it good?

The rads are about 20 years old and I doubt they pipes are insulated. They are under concrete floors so hard to tell.

The a2w system will fit in kitchen where we have the hot press as it would replace the hot tank we have at present.

If not on the gas lines then I wouldn't bother trying to put in gas. Your choice really is oil boiler or some sort of A2W system.



The 13 alu rads would not be cheap....I would say you got a fair hop when you got that price.



Other thought just popped into head, if you replacing the older rad's with new type rads would see huge jump in performance. Most of the older rads got oversized due to the poor performance of the heating system and the radiator itself.



So if the pipes are concrete into floor, you won't move pipes. If you put in newer radiators they will probably be sized for half the lenght of the older ones but you put in the longer ones to suit the pipes. Larger area is better for A2W. So you could use normal radiators with A2W heat pump....the unknown is how much heat loss into the ground....


The alu rads could be more than the heat pump?

Jaymacc

Dardania wrote: »

It doesn't say it directly. You would need to speak to the assessor who generated it - they need to look at a parameter in the software they used to generate the certificate.
If you have the cert, it should have a BER number on it. If you put the BER number into this website
https://ndber.seai.ie/pass/ber/search.aspx
it should give you the contact details of the BER assessor. They can find the number thus:



Maybe the assessor will give you this number gratis if you ask nicely / agree to come back to them post the works, as you need an updated BER cert to successfully avail of the grant. And either way, this number should give you a feel for how effective the A2W would be - it doesn't mean you have to go via the grant system if the financials don't stack up (to shefwed's point) however I would recommend it, as it ensures a minimum installation quality will be most likely be achieved.

Good idea. I will get onto him and see what he thinks. Thanks for the advice.

Jaymacc

Shefwedfan wrote: »

If not on the gas lines then I wouldn't bother trying to put in gas. Your choice really is oil boiler or some sort of A2W system.



The 13 alu rads would not be cheap....I would say you got a fair hop when you got that price.



Other thought just popped into head, if you replacing the older rad's with new type rads would see huge jump in performance. Most of the older rads got oversized due to the poor performance of the heating system and the radiator itself.



So if the pipes are concrete into floor, you won't move pipes. If you put in newer radiators they will probably be sized for half the lenght of the older ones but you put in the longer ones to suit the pipes. Larger area is better for A2W. So you could use normal radiators with A2W heat pump....the unknown is how much heat loss into the ground....


The alu rads could be more than the heat pump?

Well the quote was €13k for the heat pump and 13 rads.

I wonder would it be pointless going a2w if they pipes arent insulated in the concrete?

Shefwedfan

Jaymacc wrote: »

Great. I will try dig out our cert too and see what it says. What part will I need to look at on it to see if we are good enough for A2W?

They don't list on the BER cert. Not the ones I have anyway. You will see the person who carried out study so it might be worth checking

Shefwedfan

Jaymacc wrote: »

When you talk about windows. Are upvc double glazed windows which are about 7 years old ok for use with a2w system?

Also, are you saying they reduce size of the rads in each room? Why would they do that when the temp pumped around is lower with a2w?

No idea, I am not going that root. I know when I talked to 2-3 installers they all said the same. People had double glazed and had to replace to hit the grant. After that I switched off.



In regards to rads, I think I covered already, and you have as well, I wasn't aware they quoted to swap the rads as well......