Cheap Heat

grahamc2003

stevehead wrote: »

I posted a vid on Youtube some time ago showing my MHRV's:
http://www.youtube.com/watch?v=oOvhHmb7Hl8&feature=mfu_in_order&list=UL
I had to get some local sparkies to install them.

Hi Steve, a really interesting couple of videos, thanks.

I'm not sure how much info you'd like to disclose, but I'm sure everyone would be interested in the various costs of these things (installation, unit cost, running costs if you've run it over a winter etc).

I've been googling around, but couldn't find your actual system, and didn't catch the model in the video. So what model are they? (From that I'll get the heat output and everything else, i hope). Do the units work better if it's warmer outside (ie. does the cop vary much with outside temperature)?

Also, do these heat pumps come under the rhi, or any other schemes?

stevehead

grahamc2003 wrote: »

Hi Steve, a really interesting couple of videos, thanks.

I'm not sure how much info you'd like to disclose, but I'm sure everyone would be interested in the various costs of these things (installation, unit cost, running costs if you've run it over a winter etc).

I've been googling around, but couldn't find your actual system, and didn't catch the model in the video. So what model are they? (From that I'll get the heat output and everything else, i hope). Do the units work better if it's warmer outside (ie. does the cop vary much with outside temperature)?

Also, do these heat pumps come under the rhi, or any other schemes?

Downstairs MHRV: Mitsubishi VL 100U. 23w 77% Efficient
Upstairs MHRV's: Kair K-HRV150 9w 86% Efficient
Both ASHP's: Mitsubishi SRK20ZGX COP 5.45
Usage over 1 year: http://forums.moneysavingexpert.com/showpost.php?p=27529151&postcount=491

'fraid I can't help on rhi; I understand my ASHPs have been replaced with more efficient models with a COP around the 6 mark.
I did have a go at measuring the COP and the numbers looked OK. The most important thing was that they always coped and are very cheap to run.

grahamc2003

I've just been googling around to find info on the possible rhi for air heat pumps. Sorry if I'm a bit late toi the party, and everyone else knows all about the rhi proposals, and it's been covered already (the thread you link to Steve is pretty long! and not had time to go through it yet)

It looks like this type of heat pump will attract an rhi of 7.5p/kwh.

Does anyone know what that means exactly, and how it is proposed to measure the relevant number of kwh?

Surely it can't be the difference between the heat produced and the electricity used can it? That would mean, e.g. for a system with a cop of 5, 4 kwh would attract the 7.5p for each kwh used to power it. So, 10p (for 1kwh of input) results in an rhi payment of about, hey presto, 30p. I'm tempted to say that surely can't be the system, but having thought about it, I've seen dafter green subsidies! Aprreciate someone thowing some light on this, if this level of detail is known yet.

Thanks for the details posted above Steve, very helpful. On a separate point, what sort of noise do the external units make? I saw from the video that they are less than nearby road noise, but how noisy do they appear in very quiet surroundings? Enough to annoy someone in a bedroom above the unit for example?

bobsa1

I wonder if anyone could give me any advice please my house was originally a 1930's flat roof art deco house and it has been altered and extended over the years so that now there is the original flat roofed house which is about 50% of the house with a twenty year old extension behind the garage which houses the kitchen. Bedrooms have been built over the garage and kitchen extension and these have a ridged roof.

The old bit of the house has soild walls so we can't do cavity wall insulation the new part has cavity walls. We have double glazing but windows are large.

Our bills are massive!!! Gas approx £250 per month year round.

I am desperate to do something as we can't carry on paying these levels of bills- in addition the house is never warm!

A friend did tell me about some internal insulation pioneered in France??? and have thought of having a sedum (sp) roof on the flat roof but don't know enough about energy to make sensible decisions.

We have had a wood burner fitted in the lounge and this helps but house still really cold. We have wondered about getting an everhot stove for the kitchen just to keep the cold at bay

Any help greatly appreciated

zeupater

bobsa1 wrote: »

I wonder if anyone could give me any advice please my house was originally a 1930's flat roof art deco house and it has been altered and extended over the years so that now there is the original flat roofed house which is about 50% of the house with a twenty year old extension behind the garage which houses the kitchen. Bedrooms have been built over the garage and kitchen extension and these have a ridged roof.

The old bit of the house has soild walls so we can't do cavity wall insulation the new part has cavity walls. We have double glazing but windows are large.

Our bills are massive!!! Gas approx £250 per month year round.

I am desperate to do something as we can't carry on paying these levels of bills- in addition the house is never warm!

A friend did tell me about some internal insulation pioneered in France??? and have thought of having a sedum (sp) roof on the flat roof but don't know enough about energy to make sensible decisions.

We have had a wood burner fitted in the lounge and this helps but house still really cold. We have wondered about getting an everhot stove for the kitchen just to keep the cold at bay

Any help greatly appreciated

Hi bobsa1

£250/Month on gas plus logs on top seems excessive, it's actually higher than my gas bill for a year .... might be an idea to open another thread for this to keep the discussion for your issue together.

Regards

stevehead

grahamc2003 wrote: »

what sort of noise do the external units make? I saw from the video that they are less than nearby road noise, but how noisy do they appear in very quiet surroundings? Enough to annoy someone in a bedroom above the unit for example?

Hard to say Graham; it's not an unpleasant sound and I you wouldn't hear the outdoor unit through decent windows. My neighbour's gas flue is noiser so they have no complaints. I have to walk right up to them to hear if they're running when not under high load.