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Ecodan ASHP not switching off?
Hi. I have a Ecodan heat pump running on radiators in 2 zones with each zone controlled by a Heatmiser stat. The fault I have is that zone 2 works fine switching off and on as the stat calls for it. But zone 1 will switch on when the stat comes on but will not switch off? I’ve tried turning the stat up and then down again but it doesn’t work and have switched it to heat the water in the hope that when the water reaches temperature the system will check the stats see zone 1 is off and stay off but it switches back on again? The only way to turn the heating in zone 1 off once it’s turned on is to switch the whole system off to reset it which is not an option.
Does anyone have any ideas? Thank you.
Hi there Juju1973. You definitely shouldn't have to rest the system! A few questions:
1) Has it always been like this since install or is it something that has happened recently?
2) Does Zone 1 react in the same manner regardless of whether Zone 2 is on or off?
3) What mode are you operating the Ecodan in - is it Room Temperature, Flow Rate or Weather Compensation?
4) When you say that it doesn't switch off. Is it that the circulation pump doesn't switch off or the heat pump itself?
Your answers might help narrow down the potential problems.
Posted by: @juju1973Hi. I have a Ecodan heat pump running on radiators in 2 zones with each zone controlled by a Heatmiser stat. The fault I have is that zone 2 works fine switching off and on as the stat calls for it. But zone 1 will switch on when the stat comes on but will not switch off? I’ve tried turning the stat up and then down again but it doesn’t work and have switched it to heat the water in the hope that when the water reaches temperature the system will check the stats see zone 1 is off and stay off but it switches back on again? The only way to turn the heating in zone 1 off once it’s turned on is to switch the whole system off to reset it which is not an option.
Does anyone have any ideas? Thank you.
I suspect that your heatmiser's are starting and stopping your heat pump, and that either heatmiser being on will request the heat pump to start, but to stop the heat pump will require both heatmiser's to be off.
Try turning Zone 2 heatmiser off, and then see if Zone 1 heatmiser starts and stops the heat pump.
Controlling a heat pump using heatmiser's will possibly lower the heat pump efficiency.
Hi, thanks for coming back to me.
1. No the zones were working fine until l had the radiators increased as the original instal had undersized the radiators throughout the property. I don’t know if anything was adjusted at this time.
2. Yes it is refusing to switch off regardless of zone 2’s settings.
3. It is the same whether using flow temperature or weather compensation curve.
4. It is not just recycling warm water it is continuing to heat the system.
Zone 2 switches on and off without any delay on the main controller. Zone 1 switches on without delay but is then stuck on.
Thank you for your reply. No I have tried the system with zone 2 on and off when I try to turn zone 1 off and it makes no difference is still refuses to switch off.
it was installed from new with these controllers.
Posted by: @juju1973Thank you for your reply. No I have tried the system with zone 2 on and off when I try to turn zone 1 off and it makes no difference is still refuses to switch off.
it was installed from new with these controllers.
I would suggest that you ask your installer to rectify the problem. Once the on - off problem is resolved, you may wish to consider operating your system in Weather Compensation (WC) mode, which you may find is much more efficient.
Your installer should have set your system to operate in WC mode, so if they did not then you should ask why.
I am trying to get him to sort it but he takes ages to fit me in so I was hoping someone here has an idea.
I generally run it in WC but the annexe is a holiday let and the guests complain that the heating isn’t working when the radiators are not really warm so I have to switch it to flow temperature when we have guests to stop complaints. Not ideal but it what I have to do.
Posted by: @juju1973I am trying to get him to sort it but he takes ages to fit me in so I was hoping someone here has an idea.
I generally run it in WC but the annexe is a holiday let and the guests complain that the heating isn’t working when the radiators are not really warm so I have to switch it to flow temperature when we have guests to stop complaints. Not ideal but it what I have to do.
Can you provide closeup photo's of your zone 1 heatmiser in the on and off condition.
You need to educate your guest about heat pumps.
@derek-m I’ve had a similar problem lately - I originally got a J1 issued on my main panel and now my heat source won’t turn off (the fan outside isn’t running) but everything inside the house is running even though I have trine the heating and hot water off (?) when I switch the system down manually or do the demister thing you suggested it tells me to turn system off (soon as I put on switch on again the whole system fires up again as if I have the stat turned up (it’s currently at 10 and the house is at 19) in
Posted by: @mandie@derek-m I’ve had a similar problem lately - I originally got a J1 issued on my main panel and now my heat source won’t turn off (the fan outside isn’t running) but everything inside the house is running even though I have trine the heating and hot water off (?) when I switch the system down manually or do the demister thing you suggested it tells me to turn system off (soon as I put on switch on again the whole system fires up again as if I have the stat turned up (it’s currently at 10 and the house is at 19) in
What is a J1?
Which Stat is set to 10? 10 what?
If the heat pump outside is not running then your heating is not on.
@derek-m hi - I have a J1 fault on the main panel (this means it’s not talking to my thermostat and I can’t reset this as I have tried all options) my heating I have now turned down to 10 degrees on the main panel but the house is at at least 19 last night - and I can hear the motor running (normally it turns off) but the fan outside is not going
Posted by: @mandie@derek-m hi - I have a J1 fault on the main panel (this means it’s not talking to my thermostat and I can’t reset this as I have tried all options) my heating I have now turned down to 10 degrees on the main panel but the house is at at least 19 last night - and I can hear the motor running (normally it turns off) but the fan outside is not going
Can you provide more details about system, photo's would be useful.
What information are you seeing on the Ecodan controller?
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