This articles intention hopefully, is to help clarify the reader as to whether a heat pump is worth considering and which manufacturer to choose. I have looked at some of the top brands of heat pumps and chosen Air to water heat pumps over Ground source to analyse, naturally ground source heat pumps are/should be far more energy efficient than Air source, but I won’t go into that here.
When you are trying to compare like-for-like between the manufacturers as I have found it can be confusing as they may and do use different parameters to demonstrate their efficiency, after all the only reason you are thinking of buying a heat pump is will it save you money? So, in looking at the different makes I kept it simple as you should and I used A2w35 as my benchmark which indicates its COP (coefficient of performance) when it was producing 35°C MWT (mean water temperature) with the outside air temperature at 2°C. Naturally when the air temperature is higher or lower the COP will be different such as if the air temperature was 7°C then the COP will be better.
Unfortunately I am not going to name the manufacturers as I can’t afford a lawsuit but it is easy enough for you to look up these performance figures for yourself or you can always contact me directly for an impartial view as an installer – www.subheat.co.uk . Other than the actual performance more of which later, what other factors need considering when choosing a heat pump? My view is it comes down to simply build quality of the product and the reputation and service you would expect from the manufacturers against the cost, when you are considering the purchase of such an expensive item.
The cost of heat pumps is the biggest barrier against going for this technology for most people unfortunately in comparison to conventional heating boilers, the cost we were hoping was to be made more palatable with the RHI (renewable heating incentive) but this looks not likely until sometime in 2014, so why should I buy one? I believe it come’s down to two reasons the first is its a ‘clean’ technology energy source being electrically driven and secondly and the major point is that it should be energy efficient and therefore reduce your fuel bills.
So back to A7w35 and my findings for this I have looked several heat pumps both ‘conventional’ and inverter driven around the 7Kw output range, the three key point to consider are heat output, power input and the COP it delivers at those temperatures – my conclusion to this is you pay for what you get, quality will always outweigh cost in the long run – as a case in point as I write this, I have received another phone call from a unhappy customer who had a ‘well known’ heat pump installed by his builder/plumber and it’s not doing what it is supposed to and would like for us to produce a report to confront his builder/insurance company.
This gives us all a bad name in the heat pump business, making heat pumps look as if they are not worth it when the truth is the exact opposite but only if you get the right product in the first place from installers who have the knowledge and design experience to give you helpful impartial advice to carry the installation and only if it is appropriate for your property. In conclusion do as much research and fact finding and talk to people who know and don’t rely on people who don’t!