Samsung ASHP DHW on - 'Heat' setting off - should central heating radiators still be permanently on?
Hi,
We are new to ASHP tech. We have a Samsung ASHP HT Quiet 8KW - are our radiators (central heating system) supposed to be operating when 'heat' has been turned off on the Gen 6 Samsung control panel and only DHW is set to on in standard mode?
Posted by: @horneHi,
We are new to ASHP tech. We have a Samsung ASHP HT Quiet 8KW - are our radiators (central heating system) supposed to be operating when 'heat' has been turned off on the Gen 6 Samsung control panel and only DHW is set to on in standard mode?
I wouldn't have thought so unless
It's residual heat from when they were supposed to be on or
It's very cold and frost protection has kicked in
Can you give more info please about the symptoms observed and how often under what conditions?
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.
Hi James,
Thank you for replying. Please bear with me as the additional info may be useful. The outside temperature was between 9°c-11°c during both tests
We had been heating our immersion water heater from our AC battery (fed by solar panels) as we were getting up to 24.6 KwH on good days from August to early Oct. The ASHP was installed in early Sept so I asked the installer to set the Samsung DWH to off on the control panel - I had only just got a reasonable understanding of our solar system, AC battery, Harvey and Eddi!
I set the Samsung control panel ‘heat’ temp to 19°c (central heating), DHW setting still off. I was made aware that the radiators weren’t supposed to be hot to touch and that it is best to keep the ASHP running for most of the day.
I did take a reading off the radiators - when the Samsung room stat recorded 19°c - 20°c the rads were around 23°c-25°c - measured with an accurate digital thermometer.
The first time I turned on the ASHP’s DHW (set to 50°c) whilst the central heating was on (‘heat’ temp setting for central heating at 19°c) we noted that the radiators were much hotter than they had been during the past few weeks (barely luke warm at 19°c heat setting and DHW off). I measured the rads to find they were 37.4°c whilst the DHW was operating. The Samsung control panels room temperature went up from 19°c to 24.6°c. The COP reading went from 4/5 down to 2/5.
A few days later I decided to turn off the central heating altogether for a few hours and then turn on the DHW, it was 9°c outside. I set the DHW max temp to 47°c (standard) for the test (see pic). The radiators were stone cold. The immersion was only around 20°c before I activated the DHW. Once again the radiators came on - ‘heat’ setting on the Samsung panel was greyed out - definitely off (see pic). When the Samsung control panel was showing DHW water temp of 40.6°c I measured the radiators with the same thermometer and recorded 34.6°c (image attached).
OK that helps. So as I understand it with ch turned off on the Samsung controller, rads get hot when you heat the dhw from the Samsung, but do not get hot when you heat the dhw from another source?
The first thing that comes to mind is a faulty/stuck/incorrectly plumbed/incorrectly wired diverter valve. This valve should ensure that the flow from the hp goes either to the rads or to the dhw tank but never to both. Have a look and a feel of pipe temps and check it's actually a diverter valve not a regular 3 way valve!
There are other possible explanations but that is the simplest.
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.
James,
Thanks. The rads don't get hot when I heat the DHW from another source. I will check the installation - I do remember being told during the installation that one of the valves had to be kept permanently open (reason not given to me) which makes me wonder if this open valve might be the culprit, though my knowledge of plumbing is very basic.
- 22 Forums
- 2,043 Topics
- 44.5 K Posts
- 75 Online
- 3,264 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
-
Here are the performance curves for the 3 and 5kW machi...
By JamesPa , 1 hour ago
-
RE: Massive Electricity Cost for Running My Air Source Heat Pump
I agree @mark-h The Building Regs are now very readable...
By Transparent , 16 hours ago
-
RE: Help me understand my Mitsubishi Ecodan system
@carpenterstation When changing settings in the ser...
By RobS , 16 hours ago
-
RE: Getting the best out of a heat pump - is Homely a possible answer?
Cynically I would suggest its there to protect the inst...
By JamesPa , 22 hours ago
-
RE: Ecodan Legionella cycle - immersion heater problem
Thanks for letting us know @clockworks I admire your ...
By Transparent , 2 days ago
-
@fillib what a wonderful result, both for you personall...
By Judith , 2 days ago
-
RE: Revised version of MCS-020 (noise standards for heat pumps)
As you say this is no change, which I personally think ...
By JamesPa , 2 days ago
-
RE: What happens when the outside temperature exceeds the upper WC point?
@editor not via the WC curve but as @old_scientist ment...
By bontwoody , 2 days ago
-
RE: MHHS and Heat Pump compatibility
@toodles to be clear I don't know if there will be a re...
By Scalextrix , 3 days ago
-
I did not know this concept, although others might. I...
By Morgan , 3 days ago
-
RE: Help me keep the faith with my air source heat pump installation
@adamk it's probably filtering different providers in t...
By Mars , 3 days ago
-
RE: why solar diverters for HW instead of the heat pump?
I should probably add to my comments above that, whilst...
By JamesPa , 4 days ago
-
RE: Commencing on an ASHP Installation Process
Lots of reading and questioning which the background ma...
By JamesPa , 4 days ago
-
RE: The Great British Heat Pump Quiz
Not sure how that happened 🤣 I suspect that it ...
By Mars , 4 days ago
-
RE: Help with understanding my Mitsubishi Ecodan air source heat pump
@patch I think @ashp-bobba gave you some great pointers...
By SUNandAIR , 5 days ago
-
RE: Installing your own ASHP - DIY
Hi @tomasmcguinness, how are you progressing with this?...
By Ashfp , 5 days ago
-
RE: Say hello and introduce yourself
Welcome to the forum. If you are new to ASHPs I sug...
By JamesPa , 5 days ago
-
RE: The Rise and Fall of Europe’s Most Generous Green Subsidy
This is where the cold water storage tank was situated;...
By Dwynwen , 6 days ago
-
RE: Air Source Heat Pump - Side Alley Suitability
Thats probably fair enough. The degree-days calculatio...
By JamesPa , 6 days ago