Evohome Issues (Optimisation & Load Scaling)
Posted: Mon Jan 17, 2022 7:30 pm
Hello all!
I have an Evotouch, which has bern running as the thermostat in the hall on a single zone setup for over two years.
It has been working great for a couple of years and I activated optimisation (1 hr) and load scaling (full) when they became available. Optimisation would kick in exactly 1 hour before the setpoint and temperatures would be exactly as requested with neither an under or over shoot, so I was very happy.
I haven't touched the controller since last Spring and all has been working well through this Autumn/Winter until a few weeks ago. Woke up one morning to no heating, despite optimum start showing on Evotouch as being activated and a difference of 4c between room temperature & setpoint.
I checked the system summary and it was showing 100% for the Evotouch but just 13% for the BDR91 relay. The boiler was off at this point and the green LED on the relay was not illuminated. All of this was during the optimum start period of 1 hour and it wasn't until 30 minutes after the set point had passed before the boiler actually kicked in.
Unfortunately the same happened the following day but this time with the boiler kicking in just 10 min or so before the setpoint, despite a 4c temperature difference. This carried on for a few days unless I manually requested a temperature during the optimum start period whereby the boiler would then instantly fire.
I have removed the batteries from the Evotouch but no difference.
Switched from full to partial load scaling and things started to improve a little after a couple of days but now I'm finding the boiler firing just 30 min before the setpoint and thus undershooting quite considerably when it always used to fire exactly 1 hour before the setpoint.
Just checked the system summary and for the first 30 minutes of this evenings optimum start period, Evotouch was requesting 100% and the boiler relay at 22% but the boiler had not fired despite a 3c outside temperature and 3c internal difference.
I have now turned off load scaling, which means I'll be back to considerable overshooting but I'm totally confused as to why this issue has suddenly arisen after a year of zero issues and zero changes to Evotouch or the boiler.
Any ideas as to what is going on here?
Cheers
I have an Evotouch, which has bern running as the thermostat in the hall on a single zone setup for over two years.
It has been working great for a couple of years and I activated optimisation (1 hr) and load scaling (full) when they became available. Optimisation would kick in exactly 1 hour before the setpoint and temperatures would be exactly as requested with neither an under or over shoot, so I was very happy.
I haven't touched the controller since last Spring and all has been working well through this Autumn/Winter until a few weeks ago. Woke up one morning to no heating, despite optimum start showing on Evotouch as being activated and a difference of 4c between room temperature & setpoint.
I checked the system summary and it was showing 100% for the Evotouch but just 13% for the BDR91 relay. The boiler was off at this point and the green LED on the relay was not illuminated. All of this was during the optimum start period of 1 hour and it wasn't until 30 minutes after the set point had passed before the boiler actually kicked in.
Unfortunately the same happened the following day but this time with the boiler kicking in just 10 min or so before the setpoint, despite a 4c temperature difference. This carried on for a few days unless I manually requested a temperature during the optimum start period whereby the boiler would then instantly fire.
I have removed the batteries from the Evotouch but no difference.
Switched from full to partial load scaling and things started to improve a little after a couple of days but now I'm finding the boiler firing just 30 min before the setpoint and thus undershooting quite considerably when it always used to fire exactly 1 hour before the setpoint.
Just checked the system summary and for the first 30 minutes of this evenings optimum start period, Evotouch was requesting 100% and the boiler relay at 22% but the boiler had not fired despite a 3c outside temperature and 3c internal difference.
I have now turned off load scaling, which means I'll be back to considerable overshooting but I'm totally confused as to why this issue has suddenly arisen after a year of zero issues and zero changes to Evotouch or the boiler.
Any ideas as to what is going on here?
Cheers