Mitsubishi Ecodan - Hot Water Settings
Hi all,
Partner and I moved into our new build back in Aug 22 and have hated our Ecodan ASHP pretty much since August 22. We've had multiple 'engineers' come out to sort the settings but they all recommend different things, the house remains cold and the smart meter is always ridiculously high. But those settings are far another time...
My main query is that for reasons unknown whenever I know the hot water is on and I check the main controller that sits in the airing cupboard and the lightning symbol always seems to be on. From what I understand that means the backup immersion is kicking in...but why? I understand that the ASHP might not have the capability to heat the water above 45'c etc without backup from the immersion but the immersion will be on even when the tank temp is down in the 10's/20's.
Is this how they're designed or is this a setting? I'm assuming constantly using the immersion is not the most efficient way to heat the hot water tank...
Matt
Posted by: @walsham_mattHi all,
Partner and I moved into our new build back in Aug 22 and have hated our Ecodan ASHP pretty much since August 22. We've had multiple 'engineers' come out to sort the settings but they all recommend different things, the house remains cold and the smart meter is always ridiculously high. But those settings are far another time...
My main query is that for reasons unknown whenever I know the hot water is on and I check the main controller that sits in the airing cupboard and the lightning symbol always seems to be on. From what I understand that means the backup immersion is kicking in...but why? I understand that the ASHP might not have the capability to heat the water above 45'c etc without backup from the immersion but the immersion will be on even when the tank temp is down in the 10's/20's.
Is this how they're designed or is this a setting? I'm assuming constantly using the immersion is not the most efficient way to heat the hot water tank...
Matt
I would suggest looking at all the settings, particularly the ones in installer mode. If you are not certain if any settings are correctly optimised then post the details and someone will try to advise.
In the Auxiliary Settings there is a 'Electric Heater (DHW) setting that is on with a delay. I'm assuming that might be it?
But if I turn this on will the hot water be able to get up to 50'c via the ASHP alone?
Posted by: @walsham_mattIn the Auxiliary Settings there is a 'Electric Heater (DHW) setting that is on with a delay. I'm assuming that might be it?
But if I turn this on will the hot water be able to get up to 50'c via the ASHP alone?
I think you can turn your immersion off with this setting but I don't know why it's on in the first place. My Ecodan heats to 55 deg easily in all weathers so not sure why yours doesn't.
Posted by: @walsham_mattthe house remains cold
Posted by: @walsham_mattI understand that the ASHP might not have the capability to heat the water above 45'c etc without backup from the immersion but the immersion will be on even when the tank temp is down in the 10's/20's.
I can sense your frustration with the equipment and are looking for a quick solution but these issues may be connected in some way.
So it would help to have a fuller picture of what you’ve got and how the DHW settings have been configured.
Can you access the DHW edit screen. If you can it would help to post all the settings that are currently set.
how to access :
1. press and hold the menu button for 3 seconds until the ‘secret’ edit menu is revealed ( it has black arrows on white buttons instead of white arrows on black buttons). See pictures
2. Press the tick to select the highlighted tap symbol
3. select the DHW NOTEBOOK symbol to reveal the list of DHW settings.
4. pick each item individually to reveal what it is set at. (6items)
if you can post this data it may reveal something more obvious.
please also confirm :-
size of heat pump and cylinder
wherher cylinder is the pre-plumbed Mitsubishi unit
anything else that might be useful information. Does it switch itself off repeatedly etc.
What thermostat eg third party or Mitsubishi wireless or other.
How many radiators or underfloor or both
It might seem like a lot to ask but Somebody in these forums may know exactly why this is happening with the right information.
hope this helps
@kev-m I turned this setting off by I'm still getting the lightning bolt symbol appearing.
I'll go through all the settings and post tonight. Hopefully someone better than I can help. Shame Lovells who installed the system are so unwilling to assist.
@walsham_matt Lovells almost certainly subcontracted it to an installer. That may be who to talk to, or they may be hopeless but cheapest bid.
I was sadly watching my ASHP tonight and it's left me with more questions than answers.
I'd switched off every immersion heater setting I could find in the hope it would force the DHW to heat via the pump.
End result...2 hours of cycling between ASHP and nothing at all showing on the controller. In the space of 2 hours it went from 17'c to...17'c.
The odd thing about it was that within the cupboard there is a red hot pipe so the ASHP is doing its job but it's not getting to the DHW tank.
I'm guessing this is an installation issue rather than anything else? I've emailed Lovells and hopefully get an 'engineer' out in the next week or two.
Posted by: @walsham_mattI was sadly watching my ASHP tonight and it's left me with more questions than answers.
I'd switched off every immersion heater setting I could find in the hope it would force the DHW to heat via the pump.
End result...2 hours of cycling between ASHP and nothing at all showing on the controller. In the space of 2 hours it went from 17'c to...17'c.
The odd thing about it was that within the cupboard there is a red hot pipe so the ASHP is doing its job but it's not getting to the DHW tank.
I'm guessing this is an installation issue rather than anything else? I've emailed Lovells and hopefully get an 'engineer' out in the next week or two.
I would suggest that you check that the valve or valves are changing over from central heating to DHW heating.
Edit.
I suppose that the other thing to check is that the temperature sensor is actually installed correctly on your hot water cylinder.
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