Joining the Renewable Heating Hub forums is completely free and only takes a minute. By registering you’ll be able to ask questions, join discussions, follow topics you’re interested in, bookmark useful threads and receive notifications when someone replies. Non-registered members also do not have access to our AI features. When choosing your username, please note that it cannot be changed later, so we recommend avoiding brand or product names. Before registering, please take a moment to read the Forum Rules & Terms of Use so we can keep the community helpful, respectful and informative for everyone. Thanks for joining!
How do the settings on my Gen 5 Samsung ASHP sound?
We have have a 2100 sq feet newish build (8 years ago) which was specced with a samsung Joule system. It has zoned UFH downstairs and the two upper floors have rads. I have really gotten into tinkering with it over the past 2 years especially as i now have power monitoring via a Shelly EM.
At the moment i have my weather comp set at 0 low and 15 high, flow temp at low 38 and 31 at high for both the UFH and the rads. At the moment this seems to be working well at maintaining the temps.
I have opened all downstairs zones so that the UFH is one zone and i have it set to heat to 22.5 overnight (in winter) as we have cheap night rate electricity and decrease to 21.5 during the day with upstairs at 19.5. In the cold snap we maxed out at 34-36 kwh per day (noting that i was artificially pushing this at night with the higher temp but half price unit rate) and in the current mild weather we use around 9 kwh per day (incl DHW which is during the night rate, of the 9 kwh almost 6.5kwh is at the cheap rate with the remaining 2.5 units used during the day to keep the temps as set.)
All look reasonably ok? or anything glaring i am missing?
there isnt much reporting out of the system so i cant get a COP unfortunately.
Difficult to say without more information about the house however, for comparison, my 200sq m 1930s house with a mish mash of fabric upgrades (including partial, but not full, insulation of the otherwise solid walls) has a measured loss (based on gas consumption) of 7kW at -2. With my ASHP, consumption peaked at 51kWh during the cold snap and is around 8-10kWh in the more mild weather this year, so I don't think your figures are a mile out.
If you are happy with the electricity bills I wouldn't worry.
4kW peak of solar PV since 2011; EV and a 1930s house which has been partially renovated to improve its efficiency. 7kW Vaillant heat pump.
Posted by: @cyrusir@jamespa the house is A3 rated if that helps (per the attached rating sytem we have in ireland)
In that case Id perhaps expect your loss to be less. Do you have a buffer tank and if so how many ports (usually 2 or 4). How are the upstairs radiators run and what is the capacity rating and make of your ASHP?
4kW peak of solar PV since 2011; EV and a 1930s house which has been partially renovated to improve its efficiency. 7kW Vaillant heat pump.
Posted by: @cyrusir@jamespa ill have to check exactly, pretty sure its an 8kw unit, what would a buffer tank look like? its a Joule system i have if that helps
A buffer tank will be a cylindrical tank other than your DHW tank, or could be attached to your DHW tank.
4kW peak of solar PV since 2011; EV and a 1930s house which has been partially renovated to improve its efficiency. 7kW Vaillant heat pump.
You can do some ballpark maths to see if it is doing OK.
E.g. if the outside temperature is -2 over a 24 hour period and your flow temperature was 40, then this CoP estimator ( https://heatpumps.co.uk/cop-estimator/) suggests a CoP of 3.04 for a well performing system is possible. Multiply this by your 35 kWh measured electricity consumed to get an estimated heat output of 106 kWh.
106 kWh in 24 hours is an average heat output of 4.42 kW which is about 21 W/m^2. This page ( https://www.heatgeek.com/how-to-size-my-heat-pump-or-boiler-heat-loss-cheat-sheet/) suggests a post-2006 new build should be between 20 and 40 W/m^2 (at around -2), so it's within the expected range (actually on the lower side).
You can fill in your own numbers as needed here but you get the idea...
- 26 Forums
- 2,618 Topics
- 61.1 K Posts
- 990 Online
- 6,994 Members
Join Us!
Worth Watching
Latest Posts
-
RE: Renewables & Heat Pumps in the News
An article on funding for heat pumps in case anyone is ...
By Jeff , 2 hours ago
-
RE: Indevolt Batteries UK Support & Info Thread
Thanks @editor , @indevolt-uk Subject to any comments ...
By JamesPa , 10 hours ago
-
RE: Share Your Experiences with Heat Pump Manufacturer Support
@seoras Sorry to hear that. I found Vaillant very help...
By JamesPa , 10 hours ago
-
The Watchdog That Watched and Waited
On 9 January 2026, Consumer Energy Solutions collapsed ...
By Mars , 14 hours ago
-
RE: GSHP Kaput After 16 Years: New Compressor or Switch to ASHP? Advice Welcome
Cool Energy in Grimsby sell ground source heat pumps an...
By DerekDeLeon , 14 hours ago
-
RE: Valliant Heat Pump Settings
Thats arguably a sign of a good installer - they unders...
By JamesPa , 15 hours ago
-
RE: Electricity price predictions
Well, we have so many cases where rain water mixes with...
By Batpred , 16 hours ago
-
RE: Two heating zones to one zone
@profzarkov They arent obviously wrong, but the only...
By JamesPa , 18 hours ago
-
RE: Towns water feed to air source heat pump system
The DHW circuit cant be separated (well it could, you c...
By JamesPa , 18 hours ago
-
Solis AC-coupled 3kW storage inverter
Solis AC-coupled 3kW storage inverterPylontech batterie...
By MartinRobinson , 1 day ago
-
RE: My NIBE ASHP Nightmare: No Commissioning, High Bills and a Hostile Installer
As @transparent has observed above, this is not bad, an...
By cathodeRay , 1 day ago
-
RE: The Grid Says Yes.. Until It Doesn’t: Why Britain's Net Zero Push is Stalling at the Plug Socket
As I was reading this article Mars, I was thinking that...
By Toodles , 2 days ago
-
RE: Tell us about your Solar (PV) setup
Installed in May 2011: 16*Sharp 245 W monocrystalline p...
By txmartyn , 2 days ago
-
-
RE: Say hello and introduce yourself
That doesn't sound 'right' to me. The national Smart ...
By Transparent , 3 days ago
-
RE: Growatt battery disconnected
I doubt this will happen, but I will try and suggest it...
By Eliuccio , 3 days ago
-
Understood. That's why I decided from the outset on a ...
By JamesPa , 4 days ago
-
RE: My experience with 3 heat pump surveys: Heat Geek, British Gas & Octopus
On the litigation, I would not go there and definitely ...
By Batpred , 4 days ago
-
RE: Recommended home battery inverters + regulatory matters - help requested
I suppose if your pv inverter packs up, you have a plan...
By Batpred , 4 days ago
-
RE: New Vaillant aroTherm Plus in black - When will it come to the UK?
Firstly check you are using sound power not sound press...
By JamesPa , 4 days ago
-
That’s the solar up and running, I don’t think it’s the...
By David999 , 4 days ago
-
RE: Seeking ideas / information / commiseration - Pure Drive
I agree with @colinc that you can reuse some of it. A s...
By Batpred , 4 days ago
-
RE: Solar Power Output – Let’s Compare Generation Figures
@toodles Im trying me best to ignore orangeman, I figur...
By Papahuhu , 5 days ago


