Ecodan 14kw - DHW COP
Hi all
I wondered what sort of DHW COP others are getting from their Ecodan's? We have the combined system with the pre-plumbed cylinder and over the summer have had the room heating switched off so only the DHW is working. In July and August we have only been getting a COP of c. 1.9 heating the water to 45-47 degrees. Does this seem right? Feels low to me?
Thx
Posted by: @hjdHi all
I wondered what sort of DHW COP others are getting from their Ecodan's? We have the combined system with the pre-plumbed cylinder and over the summer have had the room heating switched off so only the DHW is working. In July and August we have only been getting a COP of c. 1.9 heating the water to 45-47 degrees. Does this seem right? Feels low to me?
Thx
About 2.1-2.2 for me. 14kWh Ecodan and external HW tank.
I think it depends how you have it set up and your HW usage. If you heat your HW once a day at the warmest time of day and use a lot of HW the COP will be better because the ASHP will have a chance to get going and run for a while in steady state. If it's constantly topping up every time you wash your hands then it's going to be doing a lot of cold starts, which is inefficient. At least when you do this in the winter, the flow is already 40C or whatever, in the summer the flow starts at room temp. The ASHP uses a lot of power from a cold start, more when the flow is colder.
The other thing to be aware of is that even though your tank is set at 45C, the flow water will be hotter than this otherwise it would take too long to heat the tank. How much more and for how long depends on whether you use Eco or Normal settings.
Thanks Kev. That makes a lot of sense. I think part of our challenge is that we have a 300l tank but probably don't use lots of it. Thus it is always just running in top-up mode. I will try moving to once a day.
If you have a solar PV system, you should either install a power diverter to produce hot water, so that you do not need to run your heat pump at all. Alternatively run your heat pump to produce hot water when your solar PV is giving maximum generation. Whilst this will not actually change the recorded COP value, it will reduce your actual energy consumption, and is more environmentally friendly.
- 22 Forums
- 2,059 Topics
- 45 K Posts
- 51 Online
- 3,317 Members
Join Us!
Trusted Installers
Struggling to find a reliable heat pump installer? A poor installation can lead to inefficiencies and high running costs. We now connect homeowners with top-rated installers who deliver quality work and excellent service.
✅ Verified, trusted & experienced installers
✅ Nationwide coverage expanding
✅ Special offers available
Latest Posts
-
RE: Grant Aerona3 - Home Assistant control via Modbus
My dryer cycles, one day of sunshine at least once a ye...
By Grantmethestrength , 3 hours ago
-
RE: Discharging battery to grid whilst charging EV
@majordennisbloodnok I should probably clarify: I wasn'...
By AndrewJ , 5 hours ago
-
RE: Enabling WiFi: Samsung ASHP on Smart Things App
@grahamh-uk I looked into adding a Wifi kit to my Samsu...
By TechnoGeek , 6 hours ago
-
And here's a follow up article on the same subject that...
By Mars , 7 hours ago
-
RE: Renewables & Heat Pumps in the News
@johnmo Ours is powered from solar energy (with grid ba...
By Toodles , 11 hours ago
-
RE: Heat Pump Manufacturers Recommending Buffer Tanks
I'm curious who you think are the reluctant ears. Cert...
By JamesPa , 23 hours ago
-
RE: Commencing on an ASHP Installation Process
If that is the case then I would add to my earlier post...
By JamesPa , 1 day ago
-
RE: Ripped Off: How UK Homeowners Are Paying Gas Prices for Wind Energy
That's a very perceptive point, @jeff. We're all very g...
By Majordennisbloodnok , 1 day ago
-
RE: Battery sizing - How low can you go!
The second 6.5 kWh Growatt battery was installed today....
By ChandyKris , 2 days ago
-
RE: Vaillant & OVO partner up to offer Heat Pump Plus
So… I called them this morning and I’m up and running o...
By Westkent , 2 days ago
-
RE: IVT Greenline high pressure switch and electrical cassette errors
Your system seems to be more modern than mine, mine was...
By abbote , 2 days ago
-
RE: Advice for ground source heat pump in new build with PV and batteries
Braver person than me. No way I would go down that rout...
By Johnmo , 3 days ago
-
RE: Getting the best out of a heat pump - is Homely a possible answer?
@arundalep yes I have no issue with this. The observati...
By benson , 3 days ago
-
-
RE: Rate the quality of your heat pump design and installation
So your Halo lite should really do nothing, when connec...
By Johnmo , 3 days ago
-
RE: Planning Update: 1 Metre Boundary Rule for Heat Pumps Has Been Scrapped
This is indeed welcome news. In addition the new legi...
By JamesPa , 4 days ago
-
-
RE: Is Your 6kW Air Source Heat Pump Really a 6kW?
@johnmo I think we’ve been trudging through the same...
By SUNandAIR , 5 days ago
-
RE: How To Balance Radiators & the Role of the Lockshield Valve: A Homeowner's Guide
Good luck, I hope it all works out!
By JamesPa , 6 days ago
-
@johnd it's a difficult one, because we've seen instanc...
By Mars , 6 days ago