Air Source Heat Pumps: Grant and Costs

I think the unit has to be incapable of cooling in summer to qualify, but some are only lightly nobbled e.g. with a jumper wire?

They've got to soak up the subsidy somehow ...

I'll ask about that - be nice to have the option.

Mmmm :-)

I'd forgotten about the water tank - that'd be a couple of grand I suppose.

Some have a buffer tank as well as hot water tank (or both combined)

Yes, to quality for the grant the fitted unit cannot be reversed to cool in the summer. This also excludes some air to air heat pumps that may the best solution fo small flats etc. It also excludes hybrid systems which may be better for larger properties.

From what I've read and watched I'd recommend on doing your own research on what's needed for your property and which type of ASHP is likely to be fitted to a property if things like existing radiators are not capable of push out enough heat with lower flow temperatures.

The other thing I'd be wary of is any guarantee. Establish if it's an insurance based guarantee rather than one from the installer, who may be out of business in the next couple of years.

Worth a look.

Some properties will need larger radiators installed, because the output from the pump is lower than from a boiler, but they can only assess that with a site visit.

Mine cost ~10k including installation 3years ago ... 4.5kW external air heat pump, boiler with 200L DHW, 5 radiators ground floor, 4 radiators 1st floor, Includes large vertical radiator in bathroom and large horizontal radiator in kitchen. Costs ~£5 per day to run during cold spell. Water temperature limited to 55C.

Why do we keep doing this as a country. Develop half a solution. If global temps continue to rise as at present we will need cooling.

It looks to me that for many folks air-2-air heat pumps are a far better solution, except they don't heat the water.

I feel that is the case. Whenever a subsidy is announced prices seem to increase by the amount of the subsidy. Same seems to go for loft, cavity wall or external insulation.

I think that there is some inflation from grants. Much less presure to be efficient....

Dave

Subsidies are pretty much always a bad idea.

Good luck using an air/water heat pump to cool your house. Do you really want water dripping off your radiators?

It’s only really practical to use air/air units for cooling but these are excluded from the grants.

Tim

A fan coil unit will do the trick, it will want a condensate drain, but the internal bit if an air/air unit does too.

I believe the logic is that the grants are designed not to increase electricity usage in the summer where people may use them to cool the house.

odd that, because presumably in the summer, for much of the time when we need the cooling, the sun is shining and there is plenty of solar.

Demand is generally also lower, so probably enough to run a few coolers.

Dave

I've just put a deposit on my own DIY fitted ASHP. The unit, the tank, and the relevant direct ancillaries are around £6k. Pipework will add at least £500 onto that, making a base to mount it is £150, insulation for the piping is £150, then you have the 2 or 3 new electrical circuits, and associated RCDs/RCBOs and switchgear, so another £150+, we are now over £7k without any Labour, or adjustments to the existing systems. Of course, the larger Installers get a bigger discount than I can, so possibly 20% or 30% less (I was at Daikin yesterday, they say they do not give large discounts to Octopus/BG etc, it's less than what I paid, but only as they are supplied direct, not through an Wholesaler).

If a new ASHP has been fitted to a previous gas boiler system, then I would allow at least 2 days for 2 people to do it. once the ASHP has been sited, it should be left for 6 hours with power before starting it up, if not, refrigerant can get into the compressor. Also, if fitted in a day, how on earth have they thoroughly tested it and explained it all to the homeowner? It has the hallmarks of a poorly fitted ASHP. What flow temp is it running at? BG are advertising it will heat your house to the correct temperature, what they dont say is how inefficient it could be when run at 50 degree flow temperature, which is what they set them at.

But a *lot* more work than just moving a jumper wire which you originally stated.

I would also imaging that the total amount of cooling achievable will be very limited when using air/water as opposed to an air/air system using a volatile refrigerant for heat transfer.

Tim

ok, I just meant but the reversing valve is present

I think The Stiebel/Eltron ones supply chilled water down to 7°C, but you don't need an F-Gas ticket.

Possibly people would want cooler bedrooms in which to sleep :) No solar then.

Thanks!