Heat Pumps - post here.

I wont mind at all, I'll likely be fiddling away with batteries and off grid systems anyway so another wont hurt!

So i should be getting a ,'new geothermal pump unit fitted, it's a 12kw nibe unit with inbuilt cylinder. €16k ish installed, don't strictly need to replace the unit but given other works needed (and grant availability, increased efficiency) it kinda makes sense)

If considering ac what about mhrv with ac. It’s especially good if you’ve really sealed your house. It’ll supply warm fresh air in winter and the ac can then provide the cool fresh air in summer.

your heatpump will really only work to cool with ufh pipes not rads. Might we well worth looking at the advisory that came with your ber to see what was recommended in term of airtighness of the house itself before looking at heat pumps. The heatpump works great when specced properly and in the right building ( insulation and airtight) otherwise they can be ineffective and very expensive, however integrated with solar Pv as I am I think they’re great.

Hi All, did anyone DIY their own heat pump? I’ve an apartment in Portmarnock (close to the sea) is this an issue? I have a contact in Daikin who can prob get me trade rate and bit of discount.

I can do the heat loss calcs myself and figure out what heat output I need. Or reverse engineer it as I know my flow temp on the old boiler and the sizes of the existing rads.

I believe I’m a B3 BER. I’m on the top floor; so two units under me which basically gives a lot of free heat apart from on the coldest days.

I have a full TADO setup in this property with smart valves and temp sensors in each room. I would like to keep this.

The existing hot water tank is in fine condition would not want to touch that.

im a regular on the solar PV side of things on this forum and DIYd my own solar install (and as such didn’t get a grant). Is it the same story with the grants here? Can do it Cheeper yourself without the grant?

Doing a bit of work myself at the moment which means replacing floor in about 1/3 of existing build. Was talking to different people about UFH mats that sit on the (well insulated) concrete. The majority of the companies say however that it's pretty much all or nothing i.e. you've to do all rooms downstairs rather than one at a time. Now looking at milling into the concrete. Got a quote of 9k all in. Would mean I'd be lifting and replacing 3 rooms of engineered timber flooring but I think ir would be good long term when I need to put in the A2W

Is that price after grant, I assume so? I have been trying to get prices for a retrofit ourselves without much luck so would be interested if you could pm me the details, thanks.

I have got a couple of quotes for supply only of a 11kW heat pump and 220l tank of between €5600 and €8500 if that gives you some idea on pricing.

EDIT: Those are ex. vat

im really thinking longer term i want to go air to air heating / cooling. The cooling is nearly as nice to have as the heating in the house! i had a chat with an installer who put in some lg mini split units for someone but to be honest they while they do a good job didnt fill me with confidence. I don't want to put in 2 mini split units for cooling that can heat but not have an plan for the overall house.. there is a daikin multi plus system that will actually heat a hot water cylinder as well. From what ive heard mitsubishi are the best units / hardware in general to go for. Id love to be able to build up the system.. start with a heatpump and maybe a couple of indoor units and add more to the rooms as we go and live with it for a year or two and see if we could remove rads at some point.. the other challenge we have is we have gun barrel pipes under concrete downstairs and wooden floors upstairs.. i dont want to spend 5k upgrading piping... when that would nearly pay for half an air to air system!

HLI of 1.78, air tightness of 1.37 with a BER of A2

No idea, I'm sure there's a junk figure written when I had to get a BER for the PV grant but as they dont test anything it's meaningless.

I have solar at a different property. Unlikely we can get solar at the apartment due to the management company owning the roof (I’m actually one of the directors so I’m going to see about this - not just for me but for other residents that might want PV)

I already have a quote from my Daikin contact for that multi plus air to air with the water tank. It’s coming in at about 5800 for the outdoor unit, 3 indoor units and the 150L water tank. That price is subject to a bit of discount if I twist his arm; but it totally excludes all other materials like copper piping / conduit and also the RGas certified person that I would need to charge the system with refrigerant. But this system is for the house with the PV not the apartment.

there is a significant grant to be had if you can do you whole house with air2air and also a bonus if you achieve a B2 using heatpump but it needs to be done via the “one stop shop” option.

the heat pump for the apartment would likely not need any upgrades to pipes / rads. And if it did I’d just get a high temp unit rather than a low temp one. But I already run the gas boiler at the lowest setting and it’s grand.

our heatloss is 2.1 and a2 (ber is no indicator of heatloss i guess), which i believe is too high to qualify for the grant, you need to be 2 or lower on heatloss. You are only grant eligible if you remove your gas/oil heating at the same time which we wouldn't do - we'd want to live with air to air for maybe a year or two before switching completely.. ideally id love to be able to do it bit by bit.. add the heat pump and maybe 2 multi split units for cooling in the summer and a bit of heating, and add on multi splits then as we go to each room as required for heating

I'm having similar thoughts particularly given the summer heat waves are going to be getting worse before they get better

I'm in France at the moment near Paris and the heat is pretty unbearable in the middle of the day, particularly in a cottage without air conditioning

The important thing to remember is there's no one universal solution for every house, so make sure whatever you get suits you

For me, I'll probably stick with Air to Water for a few reasons

First off, we don't get hot summers in Ireland, we get heat waves for several days. And the thinking seems to be that they'll get worse rather than a constantly hot summer.

So it'll be a case of using the cooling for maybe 2-3 months while the heating will be used for 6 or more months.

To me, this means whatever I use should be a heating system primarily with the ability to cool, which generally suits A2W better

This does mean I'd need fan assisted radiators or an equivalent but they seem like a good investment anyway to help heat the room quickly

The other side of the job is a bit simpler, I already have an A2W heat pump so it's likely that most of the pipework will be useable already

I don't really buy the idea that A2A is less intrusive. If using mini splits then fair enough but they only work on one room. If going for a whole house then you'll need to run refrigerant lines everywhere, which doesn't seem any better than changing heating pipes tbh

I'm also a bit unsure about what happens if the refrigerant lines leak. There's probably enough gas in the lines to cause much harm but I'm not sure I'd want my kids to be breathing in a roomful of the stuff. Then you need to get someone out to repressurise the system for it to work again.

With a water based system, if you get a leak then you'll hopefully catch it before it causes any damp mould and once the leak is fixed (could be an easy DIY job) then you just top the system up with water

The last thing which pushes me towards A2W is the DHW. Daikin have a system for that but it looks like a fairly small water tank, and most A2A systems don't do any hot water it seems

So you end up needing another heating system for water. You can either go cheap and get an immersion heater, use a fossil fuel boiler, or get a small heat pump that only does hot water. Seems like a lot of extra expense with not much benefit

There's the argument that solar PV+immersion is the best bang for buck since the hot water is free most of the year, but I've a little counter argument to that

Let's say it takes 4kWh to heat the water with an immersion, or 1kWh to heat it when a heat pump. The hot water is "free" for more of the year with the heat pump because even in mouldy winter sunlight you can probably squeeze enough juice out to heat the tank

In summer, with the immersion you'll be heating the water for free, but with a heat pump you'll heat the water for free and either throw another 3kWh into a house battery, or an EV, or chuck it to the grid and get 72c for the trouble (remember, we'll all be on smart meters at some point, so it'll be metered export eventually)

My biggest issue with A2W is the prices that installers are charging, plus the issues with installation that a lot of people are seeing. Personally I think the only route that's financially feasible is to do as much of the work yourself DIY and probably get the heat pump itself installed for the grant, or self install and skip the grant

Our heatloss is 1.68 and B1 rating, went big on insulation on purpose. Will see how much gas we use this winter. Hopefully next to nothing.

You might be able get grant if between 2 and 2.3 HLI and meet other criteria but not sure if that scenario is still available.

You'll know yourself if the house is warm enough anyway. No test was done for ours it's based on insulation levels afaik. All recently done so we had records etc.

With heat pumps and air tight houses that most are achieving or trying to achieve perhaps it’s worth considering mhrv. This can be combined with AC to provide cooling when required all through the same ducting.

Once you have a good level of air tightness the hrv is going to become almost essential.