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Does anyone have A2W and A2A?
As we are on our 2nd heatwave of the year, I have been considering permanent cooling. Our portable unit is good for cooling a single room although it's very noisy and a little bit of a faff setting the exhaust up each time.
It takes a while for the heat to get through our insulation, but once it does it is difficult to get rid of. I've contemplated shutters, although I read somewhere on here that you need planning permission?
So I wonder about the feasibility of an A2A unit in addition to our A2W unit, primarily to cool the house in summer but also give a heating boost in winter. Our A2W does a good job and achieves a COP of high 3.x and sometimes 4, but despite me taking a lot of time to balance the radiators, the rooms on the far end of the loop would benefit from a boost.
Has anyone done this?
I think that I would need to wait until after my RHI grant finishes, as I'm meant to declare if any additional heating/cooling is installed to the house.
Also, I'm not sure how ducting will fit without a lot of disruption.
Mitsubishi Ecodan 8.5kW
4.4kW Solar PV
5.2 kWh Battery Storage
1983 build, 300mm loft insulation, cavity wall insulation (beads)
I have only A2W. I am experimenting with my single fancoil and a couple of rads on which computer fans have been mounted, will post the results when the heat wave is over.
You will need planning consent unless (a) your house is detached and (b) the unit is not used solely for cooling. It will need to meet the MCS noise standards and there is a new calculation covering two ODUs, so you will need to do that. The other usual planning requirements also apply, see the legislation linked above.
I dont but I saw a couple of interesting A2A units at installer show yesterday - basically looking like a thick fancoil with all the heat pump internal, just a couple of through wall vents needed. Olimpia and Panasonic were the manufacturers. No idea what the sound levels are. These wouldn't need planning consent.
4kW peak of solar PV since 2011; EV and a 1930s house which has been partially renovated to improve its efficiency. 7kW Vaillant heat pump.
@jamespa Thanks, we're detached and I would like to use the heat function in winter, so should be ok.
Interesting, I have in mind a single external unit to minimise noise for us inside the house and some how duct it to the necessary rooms.
Mitsubishi Ecodan 8.5kW
4.4kW Solar PV
5.2 kWh Battery Storage
1983 build, 300mm loft insulation, cavity wall insulation (beads)
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