4 kw heat for ! kw power ; A/c heat pump

punamulta

i have just installed an a/c air-source heat pump in my finnish house, basicly aircon running in reverse. its just so cheap to run, useing about 700w per hour to heat the whole ground floor. I think these thisngs would be great for the UK with the relatively warm winters.

the problem is finding someone in the uk to install for a reasonable price people seem to think of a number when it comes to installation. which involves about 2 or three hours work.

the kit itself costs about £500 - £700 or so for an 'inverter' model where the compressor slows down and speeds up as required rather than just running at a constant speed like a fridge. it also filters the air and gives you A/c in summer.

The COP value tells you how good a particular model is, my panasonic has a cop of 4, meaning 4 kw heat for 1 kw input at 5 deg c outside temp, some mitsubishis now have a cop of 5.

Ken68

Hi Pun., by providing summer cool and winter heat, the payback time should be good.
Is this the same sort of heat pump as used for Ground Based heating systems where the heat in the soil (or indeed a lake) is tapped.??

punamulta

yes, but without the hight initial costs, now that they have got the good COP ratings. there is heat in the outside air right down to absolute zero.

Ken68

Something on Iceenergy Air Heat Pumps, but can't get the link to work. NPower are giving grants. 5 year warranty.
Must be a snag somewhere, Puna, for our GB Energy people not to be pushing the appliance. Could it be only for low background heat, and extra to a gas central heating system.

Cardew

Even if you get 4 times the output over input it doesn't make it that much cheaper than Gas when you are using daytime electricity on an E7 tariff.

As the OP states, the killer in all these systems is the installation costs and maintenance.

Ken68

Seems you would need another source of heating, as per this.............http://www.aceee.org/consumerguide/topcashp.htm

punamulta

I do use wood burners for the very low temps below minus 10; but you rarely get those temps in the UK, the pump works down to minus 15 , with a reduced cop ratio. its at its best above minus 10, just the sort of temps you get in the UK winter.

the outside unit does frost up with high humidity and has auto- reverse to defrost itself.

Ken68

With a return of 4 to 1 and not too expensive unit at £700, can't see how it can fail if DIY. Would call for super insulation as in Scandinavia.
Don't know the system, Pun, is the heat ducted. Did you do that yourself. ?? What was the final cost?? At 700W for 10 hours each day for six months, can't be that expensive running costs.

punamulta

paid 250 euro here for installation, which took 3 hours, the unit is a panasonic CS-PE9dke inverter, one 7cm hole through the wall to the a/c internal unit for the two pipes for the gas/liquid circuit and the wiring; if diy getting the air out and making the joints leak proof would be the most important bit.

http://www.kaukomarkkinat.fi/modules/page/show_page~id~8E455313600D46B992D0F0308934EBE9~itemtype~00308B787886459385F296A5AFD4FA74~tabletarget~data_1~pid~B7047A558CDC4483A94C2C520F438E5E~layout~telkogroup.asp

Ken68

So.o...Pun an internal unit is required for each room ??
http://www.cooleasy.co.uk/wall-split.htm...would this be extra cost. Do they use juice to push out heat/cold?

punamulta

that would depend on the layout of your house and unit output the indoor unit has a blower fan which sets up an air current around the house, if doors are open.