Air to air heat pump quandary

George70

Hi everyone,

I've read a lot about air to airs on here. In particular, it's the air to air heat pumps we're interested in rather than air to water and I wonder if I could call on your wisdom and expertise to point me in the right direction.

We have a large semi detached, with a two bedroom annex at the back of the house. It's all served by oil fired heating, so with the ever-increasing costs of oil, we've looked at others ways of lowering our utility bills. We have had 8 x 220watts solar PVs fitted, which with the sunny weather lately have been amazing. On top of this, we've had a gas fire fitted to heat the large living room. But it is the annex that I'm thinking would suit an air to air.....

As it's at the back of the house, it's always about 2 degrees cooler than the rest of the house, even though all insulation, cavity wall etc has been done. This is clearly because it's only small about 70 metres sq at most. The rooms are used as office, study and play room, so the doors stay open all day really, hence I thought fitting a single unit air to air might work well in there.

I've had a couple of quotes in now; one for a worcester bosch 6kw for around (£1800) and a fujitsu 4kw unit (£1500).

I'm just wondering about a couple of things and was hoping that someone may be able to help me out to see if I'm on the right track:
1) Would either of the above units be suitable at heating the two bedroomed annex? It's a total of 5 rooms linked by a small hallway, all doors into it would stay open all day and night. The unit would sit on a oustide wall in one of the rooms, facing towards the hallway so logic would follow that the air could circulate around the whole annex, if I've got this right.
2) Am I right in thinking that it should be a cheaper and more effective method to heat the annex than the current oil fired heating setup? One of the installers said he'd been paying about a £200 for his to be on all year round.
3) Does anyone know which is the best of the two to go for. Fujitsu quote has come in a bit cheaper.....
4) We're also hoping that the pvs would help offset the cost of running it as at the minute we're generating 12kw a day!

Any help would be greatly received, as really I've only gone off reading all the threads so far to get a heads up at to what type to go for.

thanks in advance.

George

nottseagull

Spending £1500 on a device which just moves some of your expensively heated air from one part of the house to the other. seems ridiculous to me. Why not save 95% and just buy five convector radiators? These have thermostats so turn off when the desired temperature has been reached. These would actually be producing heat in your house as opposed to merely moving it.

nottseagull

Could you please explain why a unit consuming 4kw can possibly only use £200 when left on all year.

thechippy

nottseagull wrote: »

Spending £1500 on a device which just moves some of your expensively heated air from one part of the house to the other. seems ridiculous to me.

.....What??