RDSAP10 effect on existing heat pump EPC rating?
There is a real disconnect between how performance is captured for RHI and what ends up being used for EPCs via RDSAP.
The SPF of 4.1 you got probably reflects the real-world performance of your GSHP. But RDSAP, being a cut-down version of the full SAP methodology, often uses default or oversimplified figures—hence that laughable COP of 1.7. That number doesn’t reflect the capabilities of a modern MCS-certified system like MCS HP0016/08, especially if it’s been properly designed and commissioned.
To improve the EPC rating and get a COP/SCOP that reflects reality (especially at 40°C flow temp), you ideally want to use the Product Characteristics Database (PCDB). If your heat pump is listed in there, SAP can pull in the correct performance figures. If not, RDSAP defaults will drag the rating down every time.
And no—SPF and COP aren’t interchangeable. SPF takes into account the whole system and how it behaves across seasons, whereas COP/SCOP is a performance figure under fixed conditions. Related, yes. Swappable? No.
Honestly, if you’re aiming to push the rating from a D to a C and you’ve already got detailed performance data from the RHI assessment, it’s far better to do a full SAP. It’s more work and takes longer, but it allows you to input all the real data properly—emitters, controls, flow temps, measured demand, and system design. That’s where you stand a decent chance of getting the rating
- 26 Forums
- 2,136 Topics
- 46.8 K Posts
- 56 Online
- 5,662 Members
Podcast Picks
Latest Posts
-
RE: Isolating the system for a planned power cut
Thats how my PV works, it says on the CU to isolate the...
By AgentGeorge , 1 hour ago
-
RE: Does anyone have experience of a smart water meter?
Fortuitously I have a copy of a letter from the relevan...
By Transparent , 3 hours ago
-
Mitsubishi PAR-WT60R-E Wireless Controller installation
I asked a question about this previously, but things ha...
By DavidAlgarve , 4 hours ago
-
RE: Heat Pump Servicing & Maintenance – Good Value or Rip-Off?
Having bit the bullet and paid £250 for a service, our ...
By Old_Scientist , 23 hours ago
-
@bontwoody me too. I've contacted Heat Geek today, and ...
By Mars , 1 day ago
-
New heat pump heating system underperforming in Italy... Advice needed!
hi all, first post! I've just renovated a house in sout...
By robinlawrie , 1 day ago
-
RE: Anyone still weathering it out with Agile?
I went to Agile when I had solar installed July last ye...
By NJT , 2 days ago
-
RE: Mitsu Wireless Controller and MelCloud
Well it has now become obvious that the installation of...
By DavidAlgarve , 2 days ago
-
RE: Say hello and introduce yourself
Whilst you're busy installing services (pipes and wires...
By Transparent , 3 days ago
-
RE: New Vaillant aroTherm Plus in black - When will it come to the UK?
@editor I know it was formally announced at Ish the oth...
By PatrickVito , 4 days ago
-
@moman0311 welcome to the forums. I've received your em...
By Mars , 4 days ago
-
RE: Thermostat for Ideal Logic Air with 3 zone support
No harm at all in plumbing it as 3 zones, I would have ...
By JamesPa , 5 days ago
-
RE: ASHP heat output monitoring
@carlo I see there is a discussion in Facebook user gro...
By Tim441 , 5 days ago
-
RE: Flexi-Orb Heat Pump Scheme: A Game-Changer for the UK's Heat Pump Industry
MCS have set a potential trap in the new version of MCS...
By JamesPa , 6 days ago
-
RE: Who has a V2G EV installation
General comment on battery care... I guess if ev is on ...
By Tim441 , 7 days ago
-
@old_scientist like for like comparisons are almost imp...
By Tim441 , 7 days ago
-
RE: Who's your electricity provider and what's your tariff?
@old_scientist There is an option in the Tesla app that...
By Toodles , 7 days ago
-
RE: Octopus Cosy & Octopus EV + bidirectional smart tariff, together. What, eh?
@old_scientist me too. Just installed my new heat pump ...
By Eliuccio , 1 week ago
-
RE: Is your heat pump insured?
Yup just spoke to Privilege to inform them of my impend...
By Scalextrix , 1 week ago
-
RE: Forum updates, announcements & issues
Just to keep everyone in the loop, as the site continue...
By Mars , 1 week ago