camelot-forum.co.uk

Hi all,

I was wondering whether any members have installed air to air heat pumps, i.e aircon units and operate these in heating mode during the winter?

I’m thinking about it. At the moment these don’t qualify for the uptp £7500 grant, BUT, the installs are VAT free.

Our house is quite large old & “rambly” and there is no way that a normal heat pump install could be made to work. So, that got me thinking that if I had a couple of air to air units installed working effectively 24 x 7 to provide constant background heat then I can use the existing/conventional gas system to top up.

I’ve got quite a large battery installation and would see/hope that providing a constant 1kW of input power, for example, could act as base heating by running in the background which with a CoP of say 4+ would go a long way?

Any thoughts or comments?

Cheers - Rob

Yes, they are fantastic and cheap, I have two, one downstairs and one upstairs.

Thread about me installing my own here,
https://camelot-forum.co.uk/phpBB3/view ... =17&t=1043

Several others on here have done the same.

Yep, almost at the end of our first winter using the 2 A2A units. Haven't used the GCH at all.

Last year (2023/24) we used them overnight on cheap rate to reduce GCH use by pre-heating the house. But with batteries added in 2024, they covered all day heating this winter too.

Previous years, going back to 2017 (I think), we used them to reduce GCH in the spring and autumn, by using excess PV.

I note you say VAT free, has that come in then? I was hoping something like that might get support, but hadn't heard.

I’m in the A2A club.

Installed an AC unit on my upstairs landing because at the time I wasn’t getting paid anything for export, was generating more electric than I could consume/store on the sunniest days, and I wanted some cooling what with the increasing probability of heatwaves.

It has worked better than I could possibly have imagined. Costs pennies to run and, despite its suboptimal location, it warms my whole 5-bed house.

I haven’t used the GCH at all in the last few years.

I’ll try to find the thread…

Edit here’s the thread: https://camelot-forum.co.uk/phpBB3/viewtopic.php?t=1094

Thanks all, 30 pages of reading coming up ……

Hi again,

I’m a good chunk of the way through the 30 or so pages! So much experience distilled in here. It’s almost like the battery build all over again.

From what I’ve digested so far I have the following comments & questions …..

I assume that having aircon/heating AND a conventional gas boiler is referred to as a hybrid system?

If so then I then assume that the aircon/heater can be dialled down to produce a lower level of heat than the maximum. I’m guessing that there are controls for automatic & manual settings on the remote or app?

Installation. How realistic is it to get Fgas qualified? A quick look for courses shows that they are about £1k plus VAT for a 5 day course. With travel & accommodation that would take the cost upto about £2k total.

Many of the systems I’ve seen come with a length of pipe, say 4m. Can this be extended or replaced? I’m looking at a couple or few units and one of the runs needs to be about 6m.

I have to say that so far I’m not put off.

Back to reading …..

Cheers

Some of them use propane as the refrigerant? Doesn’t that mean it can be installed by non-gas fitters?

Also have two A2A units self fitted. Fantastic things.
One has a 6m pipe run with extension piece, the other a standard 4m pipe run.
Cooleasy supplied mine, the one with the pipe extension all told was less than £600.
They will want an Fgas certificate or installer name - unless you are installing the unit in 'your french holiday home' then they will deliver to uk addy quite happily. Other suggested countries may be availible

You will need a vaccum pump to suck the pipe runs out, mine cost me just under £100 via evilbuy.

I posted a thread showing my install, no idea how tomlink back to it im afraid though (techy useless me)

We have two at Turkish house. Really great when I Winter visit and I miss having one in Scotland in Summer. Our older unit has run for around 7 years with no issue and no discernable degradation. A true Swiss army knife bit of kit.

Heat pump
Cooling unit
Dehumidifier
Air purifier

Yes you can have longer pipes and I'm not aware of modulation on the heat exchanger but could easily be wrong. My units are labelled at 400/500W for HP side. You can modulate down the internal unit fan speed so you wouldn't hardly be aware it was running and the rooms gently come up to and maintain the desired temperature.

Oliver90owner wrote: ↑Wed Mar 26, 2025 10:04 pm Some of them use propane as the refrigerant? Doesn’t that mean it can be installed by non-gas fitters?

Yes. Newer units use R290 which isn’t an F-gas so is legal to DIY (not that people haven’t been DIY-ing R32 and R410a).