Matty D

Thank for answers. Now I look into rad specs, you are right @ReedRichards, the rad figures provided are Delta T = 50C. This is where I get confused, as they have been provided in the context of an ASHP quote which I understand are provided to MCS criteria (the company stated they are MCS certified), AND the heat loss for the room is the heat loss for the room. i.e., I don't see how you can use delta T50 rad figures, when the system will run with a flow rate of 50C and a design temp of 20C, and then compare it to a heat loss figure which is calculated from U values, air changes etc... Could they be somehow taking the heat loss figures and converting them to be comparable to delta T50 rad specs (and if so why)? I've asked for clarification and will post back, but any further insight would be appreciated.

Hi wise forum people, I'm in the process of getting quotes to replace an oil boiler with an ASHP for my farm house. I've got two quotes now in place, one of which was nice and detailed with all the heat loss metrics, and the other which just listed suggested radiator replacements. Despite this, after some discussion, the radiators they both suggest to replace match fairly well, except for the lounge. After a bit of questioning, I got some figures for the less detailed quote and am now having difficulty comparing the two. Company A (detailed quote) say the heat loss of the lounge is 2800 watts, and company B stated 4700 watts. I could understand a little variation, but this seem like a large difference. Further confusion comes in when I compare what each company suggests the CURRENT radiator will produce: Company A: 782 watts Company B: 1732 watts. The both correctly identified the rad as a K2 1000 x 600 mm, and I'm assuming they MUST have to use the same MCS methodology and flow rate and target temperature. There is clearly something funny going on. Does anyone have any ideas what, and if there are other methodologies that could be at play? Thanks.