Jordan

Sorry my mistake I believe we have 22mm reduced to 15mm at the rads, it is a retrofit.

I’m not sure but the engineer said I will require an additional pump on the return, we have 15mm pipe throughout . I’m just interested to know if I will have over paid to heat my home over last few months due to this? If so I am going to take it up with the installer I assume the ashp will be having to work twice as hard to get the required temp in the rads if the water isn’t getting around the system quick enough?

My installer has identified that my flow rate is 10/L p/m and the engineer told me it’s very low and should be at least 15-20 on my 8 kw ecodan , what effect will this have on running the system with low rate will it have effects on cost and efficiency for example

Is there anyway I can prove that they should have used a higher ac/h?

Ok I will speak with them tomorrow thank you for your advice, does the EPC affect these calculations?

A thing also to add here is that the EPC was completed incorrectly sighting that we have good cavity wall and loft insulation, will this affect the calculations also?

I think I was told all the calculations are done at -3

Thanks again for your reply we didn’t specify a preferred room temp this is just what they have done on there on own back. we are certainly are not very air tight built in the 1960’s 10 years plus double glazing and no cavity wall and poor loft insulation. this document shows some other data that may be helpful thanks again EPE - Nuttall NG4.pdf

I haven’t found this from the paperwork the installers sent be I assuming this is the heat loss calculations they have done however I have no idea how to make sense can anyone help to see if a 6kw ashp is sufficient

IanR-6kw is what was suggested by installers, but to answer your question no it isn’t insulated very well( I am hoping to have cavity wall and improved loft insulation soon) and definitely not air tight. Yes all the rads have been upgraded slightly in size and from singles to doubles. When you say constant flow temperature do you just mean setting a temp on the thermostat and just leaving it? nobody has suggested a flow temp to the rads it was just setup to manufacture settings and they gave my wife basic info and then left( I am currently in dispute with the company I’ve the whole process they have been terrible) ProDave- thanks for the reply I am really at a loss with all this I feel I have rushed into this and not done enough research and to go with that had bad installers hence me been here and trying to make the best of a bad situation thanks again to you both for your reply

I have just had a 6kw Ecodan installed (retrofit) I only have radiators and no ufh, I am looking for some guidance on optimisation as the installers didn’t really delve into that and cannot seem to find much info online. I have read a little on altering the heat curve but yet again can’t find any guidance on what levels would be best. any advice and guidance from other expertise/ experiences thanks