Evohome random overrides

[MrBoy]

Every now and then I'll find the heating is blasting in some room that it shouldn't be. If I look at the EvoHome controller it'll show me an override is set.
It's hard to track down but I am fairly confident I can rule out someone doing it deliberately or tampering with the TRV as it might be the first time anyone has been in the room that day.

Today I found a room was overridden until 9pm at 20C. I do have a program set to 20C from 0800-1000 and 9pm is a later trigger point. Is it possible the system 'misses' the command to run off and erroneously sets the current temperature as an override? Is this any sort of known bug?

It makes me wary to trust a system that might turn my heating on (or off) without being asked. I like the Evohome system a lot but core functionality HAS to be rock solid.

[therealfronty]

You don't have a cat do you?

[MajorDanby]

Set the local overrides to disabled and see if it continues happening, sounds like a kids/partner/pet issue

[MrBoy]

Set the local overrides to disabled and see if it continues happening, sounds like a kids/partner/pet issue

Happened again today in several rooms, including some with doors shut and nobody in. I have the heating full blast in 3 rooms which I only just noticed... The cost of gas right now this is probably costing me a non trivial amount.

I think you're suggesting disabling the HR92? Some of them already are but it makes sense, however I can't see this as the cause.

They always override to 20C which makes it seem more like a bug to me

[CT1]

Have you done a search of the forum? I think this may have come up in the past and be related to timing of messages and may need TRVs to be restarted at different times? Apologies if this is a different issue.

[benwillcox]

I've had this happen before, and I came to the conclusion it was related to one of the HR92s rebooting itself and then when it came back on it defaults to 20 degrees. I don't know why it didn't re-sync to the correct temperature as it should do.
This particular unit would also reboot when knocked slightly, and I suspected that the issue could have been down to dodgy battery terminals and perhaps thermal expansion was causing a bad connection and the unit to reboot itself. I did try tweaking/cleaning the battery terminals and it hasn't happened again for as long as I can remember now, whether it was just a co-incidence I do not know but might be worth checking.

[MrBoy]

I've had this happen before, and I came to the conclusion it was related to one of the HR92s rebooting itself and then when it came back on it defaults to 20 degrees. I don't know why it didn't re-sync to the correct temperature as it should do.
This particular unit would also reboot when knocked slightly, and I suspected that the issue could have been down to dodgy battery terminals and perhaps thermal expansion was causing a bad connection and the unit to reboot itself. I did try tweaking/cleaning the battery terminals and it hasn't happened again for as long as I can remember now, whether it was just a co-incidence I do not know but might be worth checking.

This would certainly make sense, I am assuming the HR92 does not download the schedule from the controller but simply knows the current temp - it is always 20C and the override is always until the next trigger point.

When you replace batteries, you often see the device show as overridden to 20C too, but that tends to be only for a short time until the system catches up.
I have devices with only a single trigger point all day in the schedule, so a rogue override is in effect up to a whole day. I could set more trigger points (all the same temp) to minimise the effect but it just seems something is dodgy.

[MichaelD]

What you are describing sounds like you have Cold Weather Boost set, that turns up the temp in one or more rooms when its cold outside. Have a look at this https://support.resideo.com/s/articl...language=en_US

[MrBoy]

What you are describing sounds like you have Cold Weather Boost set, that turns up the temp in one or more rooms when its cold outside. Have a look at this https://support.resideo.com/s/articl...language=en_US

I've never heard of that before... is it a newer feature? Presumably it uses their best guess from internet weather not an outdoor thermometer module?
I definitely find I set the temperature lower in summer to get the same comfort so it's a clever idea but I don't think this is the cause of my issue, I'll check properly to be sure.

[MichaelD]

I think its always been there, since the WiFi version of the controller was introduced. Its all covered in the link I posted, I don't have it on mine, because I have the earlier pre-WiFi controller, but just diagnosed a problem for my daughter who has the later version, she had one room going up to 20 degrees for no apparent reason

[RedEarth]

I've never heard of that before... is it a newer feature? Presumably it uses their best guess from internet weather not an outdoor thermometer module?
I definitely find I set the temperature lower in summer to get the same comfort so it's a clever idea but I don't think this is the cause of my issue, I'll check properly to be sure.

The guide on the Resideo support site doesn't illustrate it, but when cold weather boost is active in a zone, it will show the cold weather boost icon (thermometer with a snowflake behind it) against that zone on the home screen, however you mentioned in your original post that you can see an override is set, which suggests to me that you're seeing the override icon (analogue stopwatch) against the zone instead. If that's the case then I don't think it is a cold weather override. If it was a real override you'd see the cancel override button in the details screen for that zone, but you wouldn't see that button when cold weather boost is active.

[SteveP]

Still not sure why but after having Evohome for nearly 10 years, last October I suddenly started having these random overrides on over half my zones. I tried the various options mentioned in this forum such as shifting the set times away from the hour etc, I also did a complete reset on the whole system, checked that all trvs had the latest software etc. Still had the same issues. The only thing I could finally think was that the trvs causing problems had recently had new batteries. I replaced the batteries with a different brand..... the problem went away ��go figure !! may be worth a try on one of the zones to test out ?

[barratt_sab]

I've had this happen before, and I came to the conclusion it was related to one of the HR92s rebooting itself and then when it came back on it defaults to 20 degrees. I don't know why it didn't re-sync to the correct temperature as it should do.
This particular unit would also reboot when knocked slightly, and I suspected that the issue could have been down to dodgy battery terminals and perhaps thermal expansion was causing a bad connection and the unit to reboot itself. I did try tweaking/cleaning the battery terminals and it hasn't happened again for as long as I can remember now, whether it was just a co-incidence I do not know but might be worth checking.

I have had exactly the same issue and came to a similar conclusion. Exactly the same symptoms as the OP - heating suddenly over-rides to 20 deg C. I changed the batteries in the offending HR92 and gave it a good clean and it's all fine now.

I also have a test system running (just the evohome stuff, not attached to any rads or boiler) with one HR92, one controller (running 02.00.19.33) and two BDR91's attached to a light bulb (don't ask...).

If I have local over-ride enabled on the HR92 zone and take the lid off the HR92 without unlocking the collar at the bottom, then disconnect then reconnect the batteries, it shows the version, then 20 deg C, then SYNC and then the controller shows an over-ride to 20 deg C. This seems to happen pretty consistently - something like 80% of the time it will over-ride to 20 deg C.

If I unlock the collar at the bottom of the HR91 it seems to happen less (maybe 20% of the time) but it still happens now and again.

If I turn local over-ride off on the controller for that zone I can't get it to happen at all.

Unfortunately, it isn't completely consistent, but it is certainly reproduceable by powering the HR92 off and on again.

So, if you don't ever adjust the temperature using the HR92 lid, you could turn off local over-ride for those zones and hopefully it won't happen again.

[Long press on <Settings>, then <green tick>, then <zone configuration>, then whichever zone you want, then <Parameters>, then <Local Override>, <Disabled>, then spanner top left, then <Exit>.]

[whatwiredoicut]

ive started to notice this recently now im logging with domoticz and graphing using grafana im seeing weird overrides and things happening too