I am having an ongoing discussion with my plumber about the installation of my ASHP system. Further to previous posts on BuildHub (and very helpful feedback) and a non-committal review by MCS following my complaint I am now looking for someone to review my system and advise where there are issues with installation and non-compliance with MCS or any other relevant standards.

 

I am between Bristol and Swindon.

 

Does anyone have any recommendations of any companies who would cover my area for this sort of review.

 

As always with BuildHub, I very much appreciate input from everyone!

Can't help with a name or company - but what appears to be the issue(s)?

Can't give you a name for your area either, but a few things will make any review quicker and cheaper.

Before anyone visits, pull together the MCS certificate, the room by room heat loss calculation, the design flow temperature, the emitter schedule showing each radiator's output at that flow temperature, the pipe sizes and the commissioning sheet. A lot of compliance problems show up on paper first: emitters too small for the design flow temp, no proper heat loss done, or a unit sized off a rule of thumb. If your system has a monitoring app, a week or two of flow temps, run times and electricity use tells a reviewer more than a one hour visit.

When you ring round, ask for an independent heating engineer or heat pump consultant who does design and commissioning reviews and isn't trying to sell you a replacement system. Ask them to report against MCS MIS 3005 so the findings line up with your complaint.

On the complaint side, if your installer was signed up to RECC or HIES as part of their MCS registration, that consumer code's dispute process can often go further than MCS itself, and an independent report gives it some teeth.

What are you actually seeing, high bills, cold rooms, short cycling or noise? That would help people here point you at the likely cause.

Thanks John and JP for your replies and some very helpful points there JP for finding someone to assess the system.

The issues with the system are partly set out in this thread https://forum.buildhub.org.uk/topic/43959-buffer-tank-hot-when-heating-mode-turned-off/

Potted History

Builder subcontracted local plumber. Local plumber confirmed that Daikin (through their Sustainable Home Centre which is the local plumbers' merchant) would be designing the system and to obtain the BUS an umbrella MCS company would sign the system off and do the BUS paperwork. Daikin SHC provided a design schematic of the system.

Once the system was installed I had some queries (mainly the sizing of the ASHP and why a buffer had been installed when it wasn't on the design) Daikin SHC turned round and said their design drawing was indicative and they weren't the designers (oh great I thought). When pushed further the plumber and Daikin ducked the issue by saying that as the system was signed off by the MCS company then it was all their responsibility and I would have to raise a complaint with MCS. I did that but in the period the complaint was being progressed MCS company has gone into administration and therefore MCS have stopped progressing their investigation.

The builder and plumber have said they will put things right if it is needed but at the moment is it me with my limited knowledge arguing with the plumber with their limited knowledge about what is correct/not correct with the installation. The conversation from their side has largely been that I have hot water and heating... so where is the problem.

Key Issues

No Design - nobody has designed the system so I am not sure what issues there might be in addition to the below.

Oversized ASHP - At the time of install Daikin calculated heat loss at just under 6kw but had no 6kw units available so provided a 9kW unit for the same price. I queried this and was shown their calculation/was assured that the 9kW unit was more efficent than the 6kW unit (which I assume had not allowance for cycling within the calc.). I am not convinced they took account of the MVHR correctly in that calculation either. In the last 12 months the flow temperature has not needed to be higher then the minimum setting of 25 degrees and on the coldest night last winter the unit still had periods where it didn't run due to inside room temperatures meeting the set point.

Buffer Tank - I query the need for it (as did others on the above post) and note that in the MCS3005 is cautions against their use.

Third Party Controls - the only thermostats are third party with no Daikin master, so modulation of the flow temperature isn't possible and cooling mode doesn't work through the thermostats