Why not A2AHP?

Spies

Why is it that air source heat pumps are being pushed more than the more efficient air-to-air? Granted its not necessarily a whole house solution, but it might work for me where we spend most of our time either in the front room or bedroom, the kitchen and bathroom don't really need a seperate source of heating and cooling.

JKenH

I can thoroughly recommend them (A2A wall mounted heat pump). For 8-9 months of the year we only need to heat the rooms we are using during the day. In winter an hour of CH in the morning and one in the evening usually sees us through all but the coldest days. We have one unit in our lounge and one in the kitchen. It has brought much marital harmony as my wife can be warm without a squabble over whether we need the CH on. They complement solar PV very well especially if on deemed export.  The majority of the daylight hours we have enough solar to run them (except perhaps December) so the cost is minimal and I estimate our spend on oil has halved. 

Edit: I should add that we have an open fire in our sitting room and unlimited supply of free wood to get us through winter evenings. 

Martyn1981

My guess is that someone in the Gov thought it a good idea to look at whole solutions (heating and DHW), rather than part solutions.

Based on my experience and the comments from so many on here with A2A (A/C units typically), the hybrid approach, when matched with PV, is a great way to reduce gas consumption, and a learning curve.

Last winter I also ran one of the units through the E7 period at night to help reduce GCH burn in the morning, I'd turn it down to 18C and leave the door of the room wide open. It seemed to work well.

I've also been surprised at the amount of cooling we've used in the last 4yrs. Certainly seems to be more long periods of 30(ish)C temps that steadily heat the house up over a few days, than 5-10yrs ago.

michaels

My suspicion is that A2A can also be used as AC which sounds like 'luxury for rich people' and also 'hardly good for the environment' hence A2A beign rejected (plus probably there is much less scope for a whole MCS industry so no suppliers would be pushing for it)

ed110220

It's probably partly a matter of culture/tradition. Different countries or regions tend to have different ways of doing things like heating. Britain's is central heating via radiators or less commonly underfloor. People largely stick to these not necessarily because they are the best solutions, or even the best solution for their particular case, but because that is "how it is done".

Air to water heat pumps are seen as familiar as they are similar to wet central heating. Air to air is not, so some people will be a little suspicious of it.

JKenH

I did consider a split A2A system with units in several bedrooms fed by one compressor. The only thing that put me off was the planning rules (I am already pushing my luck with 2 units) but I would imagine if starting from scratch with a smaller property it could  be a cost effective solution.

Ectophile

michaels said:

My suspicion is that A2A can also be used as AC which sounds like 'luxury for rich people' and also 'hardly good for the environment' hence A2A beign rejected (plus probably there is much less scope for a whole MCS industry so no suppliers would be pushing for it)

It only takes one extra valve to make a heat pump that can switch to being air conditioning.  Once people realise that, they will ask for the reversible ones, and start using air conditioning all summer.

At that point the "green" energy saving idea of heat pumps goes out of the window.

Spies

Do split systems require any planning permission? Is the compressor fairly quiet?

Lastly any national installers? 

2nd_time_buyer

Here is the official government response I got to the same question

JKenH

Spies said:

Do split systems require any planning permission? Is the compressor fairly quiet?

Lastly any national installers? 

Split systems don’t require pp but I believe you are only allowed one unit per dwelling. I wasn’t aware of that at the time. A split system simply refers to the the externally mounted compressor and internally mounted fan outlet. 

The compressor is quite quiet although my neighbour says she can hear it when outside her back door. That’s not as bad as it sounds as it is just a door from her utility room to a path down the side of her house. Internally you don’t notice the compressor and the fan is very quiet. 

I am not aware of any national installers. I used a local commercial aircon company from Scunthorpe. 

Spies

I'll email a couple of local companies, not sure what price point is considered 'good' but I'm hoping under £2k nearer £1.5k would be nice.