Its very interesting the manufacturer stating he gets a COP of 4.2, I guess this is at an ambient temperature of 7 degrees c and a water temperature of 35 degrees c thats only any good for under floor heating great for new build but not for retrofit. So that blows his COP of 4.2 out of the water for most of the country’s housing stock. Wow! how we bang on about our COP which is stated differently on every manufacturers literiture confusing the customer and installers into believing its the higher COP that matters, Some standard has to be put in place that all manufacturers have to comply with.

When using the new SAP2009 calculations ASHP get a big kicking there stated COP gets reduced to a much less desirable figure of 2.5 Unless there Appendix Q rated which means you can use the manufacturers stated COP otherwise there not worth touching for your new build that will be having to comply with the code for sustainable homes. Have a look theres not many!.

I design these and installers fit them which brings me on to my next gripe the industry has to be trained better, a lot better infact to reduce them energy bills and not increase them by lack of knowledge. Go on a heat pump course and its pritty much a sales pitch with not much emphasis on actual installation and theory training. Can we not have a governing body that relates to governing individuals as well as firms and not the laughable MCS accreditation thats availiable to any one thats got 500 quid to pay an internet company to get it for them

Oh Tom Bowen if your having trouble paying for your LPG don’t bother with an ASHP you’ll be remortgaging

If you are thinking of getting one ask the firm to supply 3 property’s were they have installed them for references. Do your homework make sure its a plumbing and heating firm and not an insulation/double glazing/facsia company thats doing it as lots of cowboys are trying to get in on the renewable revolution.

Tony if I wanted to use an air source heat pump for -25, that would mean my ASHP would have to deliver 23kw of heat if my room temp was 21 thats with a coe efficent of .5 on your SAP reort. Thats probably 2 machines which would be ridiculous. Thats just a sales pitch it works down to minus 25 yeah they do, but they have to be sized right and there bloody expensive to run at -25. I,d be flicking my oil boiler back on at minus 5 “Fact”

They do work but you have to remember you have to be very well insulated, use a well trained installer and be ready for your electric bills increasing as there not that wonder machine you think they are, there carbon savers not money savers, well until the RHI

Roll on de-carbonisation 2030!

Lee Ellerby