Ok. I'm just checking whether there was any manual intervention at 8am-ish on Friday.
As you say that there wasn't, then something has occurred to knock some sense into the heat-pump.
That energy went somewhere...
... either to DHW or room heating.
What size is the DHW tank?
Save energy... recycle electrons!
@derek-m no didnt go below zero, last friday on chart approx2-3 deg at 4am when i had such high usage. There is buh on unit but dont think that comes on much if at all. Has frost protection alright, have seen it before and lwt drops when it kicks in. Just dont get why its flowing when no call for heat. Read something online about blower relay switch malfunction.
@transparent Dont know where it went, none of my dhw cycles at night time anymore, tank is 240l i think.That usage is very excessive per hour, i have setback on programmable stat with last few weeks to not have usage at night time and then this happens which is worse usage.
Posted by: @newhouse87@derek-m no didnt go below zero, last friday on chart approx2-3 deg at 4am when i had such high usage. There is buh on unit but dont think that comes on much if at all. Has frost protection alright, have seen it before and lwt drops when it kicks in. Just dont get why its flowing when no call for heat. Read something online about blower relay switch malfunction.
Is the BUH rated at 6kW and is it enabled?
Do you have any record of the DHW tank temperature during these night-time antics?
240-litres looks like a great place to dump a shed-load of energy.
Posted by: @newhouse87dont get why its flowing when no call for heat.
I would be looking at the flip side of that coin.
Something called for heat. But it shouldn't have done.
There are three main contenders in my mind:
- valve opened/stuck/broke
- temperature sensor faulty, or possibly its connector(s)
- software malfunction
Save energy... recycle electrons!
@transparent no i jst know the current temp of it now at 42degrees and scheduled at2pm to heat to 48, Had 2 showers yesterday before scheduled period and haven't had post gym shower this morning yet so current temp seems ok for normal operation and no extra energy. Its why the heat pump is producing energy at all when no call for heat is the puzzling thing. Its off now as it should be so not sure if valve stuck.
It doesn't matter what the manual states about the BUH operating only rarely.
That's just declaring what it's meant to do.
But we're looking at a fault occurring.
Where are you reading the DHW tank temperature?
Is this on the heat-pump controller, or a (digital) thermometer on the tank?
My tank (thermal store) will always output 42°C
but that's just coz it's configured to do so.
The actual temperature of the water at the top of the tank would be higher than this.
It all depends where you're measuring and how.
I deliberately have an independent digital thermometer with two sensors on my tank (top-most in photo below).
It provides no feedback to the controllers or heat sources, but allows me to check if the temperature controls are operating as they should.
Save energy... recycle electrons!
@derek-m it is enabled, dont think it says anything about temp. equilibrium temp 0deg it says in settings.
- 26 Forums
- 2,255 Topics
- 50.3 K Posts
- 594 Online
- 5,918 Members
Join Us!
Podcast Picks
Latest Posts
-
RE: Grant 13kW Aerona3 - issues getting zones to temp
Thanks, I’ll try and send docs and soreadsheets next ...
By Crimson , 7 minutes ago
-
Daikin Altherma 3 / HomeAssistant
Any "HomeAssistant" Boffins out there? Can the freque...
By Ubert767 , 49 minutes ago
-
RE: Are We Sleepwalking Into Another Race to the Bottom?
Thanks, @jamespa. Of course, it’s irrelevant unless Hea...
By Majordennisbloodnok , 2 hours ago
-
RE: Solar Power Output – Let’s Compare Generation Figures
2025 - now a record year of Solar PV Generation. Octobe...
By AllyFish , 2 hours ago
-
RE: Midea ASHP – how to set weather compensation
@pash44pump - AI may have its uses (and I sort of allow...
By cathodeRay , 4 hours ago
-
RE: Help me keep the faith with my air source heat pump installation
If you have HA up and running watching the flow temp or...
By JamesPa , 4 hours ago
-
RE: Mitsubishi Ecodan R290 10kW performance
Totally agree that any system is reliant on the ability...
By Sheriff Fatman , 4 hours ago
-
British Gas Heat Pump Installation Complaint
In 2024, my wife and I thought that we would try to do ...
By BGNO , 6 hours ago
-
Erm... no we can't! The issue first raised by the OP ...
By Transparent , 6 hours ago
-
RE: My experience with 3 heat pump surveys: Heat Geek, British Gas & Octopus
@grahamf good set of questions. Can I suggest just one...
By JamesPa , 6 hours ago
-
RE: Is it mad to think there should be a minimum SCOP for UK heat pump installs?
This wouldn't solve the problem @mars is trying to solv...
By JamesPa , 6 hours ago
-
RE: Who has a V2G EV installation
I have PV, ASHP, UFH, Battery storage and no Gas (yaay ...
By AgentGeorge , 8 hours ago
-
RE: Testing new controls/monitoring for Midea Clone ASHP
Thx, but Sven did the hardware development. My role (as...
By Mosibi , 18 hours ago
-
RE: PV Panels on roof in Conservation Area
@majordennisbloodnok Fnaargh, I was thinking about try...
By colinc , 20 hours ago
-
RE: Electricity price predictions
@jamespa Ah, you mean MPs that have not pro...
By Batpred , 21 hours ago
-
RE: Buying large amp bidirectional RCD and RCBO
Exactly @transparent , this type of RCBOs are not easil...
By Batpred , 21 hours ago
-
RE: Very Much Awake – Renewing the Heating Industry One Step at a Time
I feel that that attitude shared by Aadil from Heat Gee...
By Toodles , 1 day ago
-
RE: The Hidden Secret to a Successful Heat Pump: Pipe Size Matters
and we have some of the strongest tidal flows anywhere ...
By Old_Scientist , 1 day ago
-
RE: Radiator Sizing Dilemma: Vertical vs Type 33 for Low-Temperature Heat Pump Systems
This looks OK. Overall you have roughly the right amoun...
By Old_Scientist , 1 day ago




