Running 

Stopped

Nothing particularly jumps up or down when pump restarts but you can see some figures have dropped when it stops. 

@craig1980

As you say, nothing appears to be changing dramatically. Though I fail to understand how your home is maintaining an indoor temperature of 18C, with an outdoor temperature of 6C.

Now try setting your system in fixed LWT mode with a setting of 35C.

@derek-m I've no idea. 🤣

I turned the system off for the Octopus saving session at 17:30 room stats showing 18. Went out and came back at 20:30. Turned back on and room stats were at 17.5. Not sure if you need that info but just in case it's relevant. 

I'll have to work out how to set fixed lwt mode. I'll do it tomorrow. Thanks again. 

@derek-m overnight it was 4 degrees and it has struggled to keep 18. The house is at 17.5 this morning. COP is down to 3.3 and it's using more power and running for longer. 15.6kw yesterday 13.3hours operation time (that's with turning off for 3hours)and a generation of 51.7.

@derek-m overnight it was 4 degrees and it has struggled to keep 18. The house is at 17.5 this morning. COP is down to 3.3 and it's using more power and running for longer. 15.6kw yesterday 13.3hours operation time (that's with turning off for 3hours)and a generation of 51.7.

I'm struggling to find where to switch to fixed LWT mode. 🙈

Although, whilst looking through the manual I found the page about removing the room stats from the system. Would this be an option? Thanks

Is this what you mean?

Posted by: @craig1980

↑

Is this what you mean?

 

Yes, that would appear to be the correct method. Try running with a LWT of 35C and see how the system responds, and if it stops the 20 second off periods.

Okay, that's done. It was already on standard temperature "water outlet". Could that have been an issue? 

@craig1980

How is the system operating now? Is it still running 8 mins on and 20 secs off?

What is happening with the room and radiator temps?

What are the flow and temperature readings etc?

Changing the way that the system is being operated is to try to find what is causing the 20 seconds shutdown.

So, it appears to run constantly but at quite high power usage of 1.9kw instantaneous power. 

Rads feel warmer to the touch but room temp stays at around 18 according to room stats and thermometers that I used for radiator temps. 

Outside temp is 6.0 according to wired remote.

Water outlet 35.4

Indoor 21.5 (remember, this is in the airing cupboard with the UVC). 

Posted by: @craig1980

↑

So, it appears to run constantly but at quite high power usage of 1.9kw instantaneous power. 

Rads feel warmer to the touch but room temp stays at around 18 according to room stats and thermometers that I used for radiator temps. 

Outside temp is 6.0 according to wired remote.

Water outlet 35.4

Indoor 21.5 (remember, this is in the airing cupboard with the UVC). 

Now measure the top and bottom temperatures on two or three relevant radiators, and the flow rate and temperature readings from the information screens.