Air Source Heat Pumps

richardc1983

Yeh the harder the compressor works trying to achieve your flow temp it will ice up sooner... however if the system is sized right and is oversized slightly then it should not affect it too much.

It worries me things like compressors cos if the compressor fails it can cost less to buy a new outdoor unit!

Andy_WSM

I have a friend who works in A/C. He'd change the compressor for a back hander I'm sure. He's had a look at the Trianco unit and says the design is pretty bullet proof. It is rare for a compressor to fail apparently. They do age, but so does anything mechancial. He said some of the A/C systems he fitted in commercial premises 15/20 years ago (Telecomms) that are running 24/7 are still working today.

richardc1983

Thats a good thing then I guess, but once something like a compressor fails its worth buying new I think, its not the actual labour that is the downfall its the actual cost of the compressor to buy as a spare part!

Im not just referring to your system by the way the same goes for all manufacturers.

Andy_WSM

Yes, know what you are saying. Look at the cost of repairing modern gas boilers though - precisely the reason I have an ASHP now. If my unit lasts 5 years, it will virtually pay for itself in savings on gas servicing alone.

richardc1983

Not to mentioning the heating bills savings too!

Swipe

have you still got your unit in the loft Andy? How do you go about drainage?

greendwarf

richardc1983 wrote: »

I think the problems with the b&q systems is they are not meant to work below freezing and this is the problem with them, I also suspect that the defrost cycles are regular, you would notice these by how many times the unit stops heating for 5mins at a time.


Perhaps maybe close internal doors to other rooms and you may find that you can keep that one room nice and warm... do you really need to heat the other rooms if your not in them?

I recognise that this is not designed for whole house heating but unfortunately this is a 1970's house with completely open plan ground floor, big floor to ceiling windows and a glass roofed kitchen. Solar gain mitigates the problem during the day but even today we haven't been above 18c - most days it gets up to 20-22c.

Actually defrosts have been very infrequent - presumably because of lack of moisture in the air.

Just by way of background my 30 year old gas boiler failed 3 years ago in mid winter with 2 rads also rusted through so rather than a complete system repalcement I thought I would wait for the Wispergen CHP to be available - but its never arrived in UK. So the B&Q unit was a cheap stopgap experiment which was much cheaper to run then a house full of electric fires going full tilt. Most of the time it works fine, especially as I live in a nice "warm" city, but these last few days defeated it. I'm in the middle of upgrading the loft insulation with 30mm Kingspan under the rafters but not finshed so am not yet getting the benefit but suffering form the extra ventilation I had to put in first!

richardc1983

The thing is this weather is temporary although weather people say there is no end in sight at the moment for it.

You could supplement it with electric fan heaters in the mean time these will warm up quicker and move more air than oil filled radiators.

Andy_WSM

Swipe wrote: »

have you still got your unit in the loft Andy? How do you go about drainage?

Yes. Not a problem. Pipe straight out the bottom of the unit, through the fascia board and into the guttering. There was standing water this morning (or ice) but it drained away as soon as the temps warmed up.

richardc1983

Temps dont seem to be so subzero now so unless we get weather colder than -5 im laughing as the system coped just fine... still achieved 22C without any loss of performance apart from maybe more electric usage and longer run times.