Evohome - poor temperature regulation

[top brake]

Hi - I need more days to conclude if is has significantly improved, but I got the impression that it was better at least in the zones that are not the bathroom.
Though I wouldn't call having one zone that behaves erratically to be 'resolved'.

"There is a possibility that if you do a factory reset and then rather than guided config you add zone in installer mode that this 'default zone' can remain. It is not a bug as such but a configuration error. " Indeed, that zone always remains after a factory reset, and if you try to bind this default zone to the HR92s, it all gets very screwy.

Do you have any comments on what I read on another post
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"You should be able to check the firmware version by doing a quick tap on 'settings' on the evohome main screen followed by a long tap (arround 20s) on 'device settings'. The system should then display an info screen with the device id and application software version followed by a date etc."

Mine is V25 from 16 janv 2014 and here is a brief description of the bugs I found:
- Renaming a zone in the installation menu corrupts the database
- Deleting a zone corrupts the database.
- Activating the temperature compensations make erroneous readings (HR92 uses their own temp sensor, no more evo's unit even if activated)
- Activating optimisation overrides the 2nd time temperature by the first time temp.
-----------------------------------------

So renaming and deleting zones I was hoping to avoid. Unfortunately, in the guided configuration, if I ask for 4 zones, it pre-populates it with names which I then have to change. What did this person mean by 'corrupts the database'? Would that behaviour lead to temperature overshoot?
(I'm thinking, what if I used guided config and ask for 4 zones and leave the names alone?)

Not sure where that information originated but in my experience I have not come across any of this 'corruption' and this is not a known phenomenon by anyone I know
I delete and rename zones on an almost daily basis
I haven't messed with temperature offsets, don't see the benefit - comfort isn't a number

Internet forums can be a bit like listening to blokes in the pub, one persons opinion gets repeated and soon becomes accepted wisdom

There are a handful of reliable sources posting here and I know all of them
I often see very inaccurate information posted, I would like to think that since joining this forum I have demonstrated that the information I share is technically correct, if I am unsure I don't guess

Thanks

[G4RHL]

I have deleted zones, changed names, added zones and never had a corrupt database problem. What I have learned is take your time setting it up, don't rush, follow the guidance given, check each stage. All should then be OK. Being human we sometimes rush a stage or process, drop attention at a time when we ought not and then are quick to blame the product and not ourselves. I am as guilty of that as any other. Is it not the case that ladies read the manual but men don't 'cause they think they know it all?!!

[erik]

I would like to think that since joining this forum I have demonstrated that the information I share is technically correct, if I am unsure I don't guess

Thanks for that.

1 example though: I've seen you posting some questionable info about the full stroke setting for HR92. When people challenged the info with documentation from elsewhere and with practical proof, you didn't reply.

I have deleted zones, changed names, added zones and never had a corrupt database problem. What I have learned is take your time setting it up, don't rush, follow the guidance given, check each stage. All should then be OK. Being human we sometimes rush a stage or process, drop attention at a time when we ought not and then are quick to blame the product and not ourselves. I am as guilty of that as any other. Is it not the case that ladies read the manual but men don't 'cause they think they know it all?!!

I personally have not run into these problems with changing names either. But I don't know how I would even detect a corrupt database. So I can't be 100% sure. I happen to have read the Honeywell manuals about 10 times. Offline, online, youtube instructions, etc. You name it. And still can't get it to work like it should

[top brake]

I have deleted zones, changed names, added zones and never had a corrupt database problem. What I have learned is take your time setting it up, don't rush, follow the guidance given, check each stage. All should then be OK. Being human we sometimes rush a stage or process, drop attention at a time when we ought not and then are quick to blame the product and not ourselves. I am as guilty of that as any other. Is it not the case that ladies read the manual but men don't 'cause they think they know it all?!!

You just made me smile, well said

[Mavis]

I have deleted zones, changed names, added zones and never had a corrupt database problem. What I have learned is take your time setting it up, don't rush, follow the guidance given, check each stage. All should then be OK. Being human we sometimes rush a stage or process, drop attention at a time when we ought not and then are quick to blame the product and not ourselves. I am as guilty of that as any other. Is it not the case that ladies read the manual but men don't 'cause they think they know it all?!!

In our house that is very true (I have just got a new car at the weekend and the first thing I did when I got it home was to read all the books that came with it!) Husband (and son) don't even bother trying to find out how things work - they just ask me.

[erik]

Can anyone tell me what section of the manual describes how to prevent the temperature going up and down 1.5 degree? I've learnt that switching to an old Honeywell Round fixes it, but I was hoping Evohome would be able to do it as well...

[greyhound1234]

G4RHL, just wanted to thank you for taking the time to sit in front of your boiler for over an hour...

[greyhound1234]

Try running the Rf test on every zone. I had a problem where it had the actuator bound fine, but not the sensor.

RF test shows 1 actuator bound and sensor is at 5-excellent. So comms seems okay.

[G4RHL]

Aye, she's an old boiler at that. I did read the paper and drink coffee though!

[greyhound1234]

It is not resolved yet as far as I can tell. It improved in the scenario of using multiple zones (hr92's), but not resolved, yet. I will also try resetting and unbinding everything and then reconfigure/rebind everything and make my living room zone 2. And see if it improves. Maybe there's some bug specific to just zone 1?

greyhound, what happens if you totally reset/unbind and re-configure/rebind it in single zone (thermostat) modus? Does anything improve at all in that scenario?

That's exactly what I'm seeing. And after the first 'hump' to 1.5 above setpoint, which you have shown, it will build another hump and another etc. etc. Like shown in this image:
[ATTACH=CONFIG]508[/ATTACH]

Hi Erik, yes your picture of 'multi-humps' is what I observe if zone 1 calls for heat. Or indeed if I put the system in thermostat mode which I did to start with.
I set all zones to 18.0, left them all day on Saturday. I checked on the bathroom (zone 1) during the day, and it periodically did the overshoot with the behaviour you and I have described.
The other zones were, however, happily maintaining 18.0. (maybe briefly touching 18.5).
If I put in a timed schedule rather than constant, with a little more complexity, then I found other zones sometimes turn off at +0.5 over, and perhaps get to +1.0, but cool down in 20-30 mins.
The bathroom zone 1 was very different, being actively calling for heat repeatedly on the overshoot, and running with a hot and fully open radiator valve. All this heat injection means it then stays at +1.5 degrees for an hour.

In order to test this I will at some point bind in a different order. If the overshooting zone moves with zone 1, this is interesting. If it stays with the bathroom, then I will try and swap the HR92s around and see if it is the zone valve.

But to be honest, whilst not ideal for a £500 system, if I have to have any one zone overshooting like this, the bathroom is where I would want it (dries the towels and gets rid of moisture).

[greyhound1234]

I would just like to say I bought an Evohome Connected (single zone) package and it was pre-configured in the box. So I couldn't have done anything wrong in installation/binding. And even then, it didn't work as advertised (building up 1.5 degree overshoots).

Yes the radiator valves is the only way to stop this system from overheating. I get the same in that mode. If I had bought it as a normal thermostat, I would have returned it immediately. My old CM907 could get similar accuracy to your Honeywell round.

[top brake]

Yes the radiator valves is the only way to stop this system from overheating. I get the same in that mode. If I had bought it as a normal thermostat, I would have returned it immediately. My old CM907 could get similar accuracy to your Honeywell round.

you have pm

[erik]

Observation/test result: yesterday, I reset/rebinded everything and put my living room to zone 2 instead of zone 1 and the result had not improved. Actually, I noticed the HR92's were being closed while still asking for heat. I changed the HR92's to full stroke and tested again today. The change resolved the HR92's being closed while asking for heat. However, I'm now seeing the same behavior again: putting in heat every 10 minutes for an hour or two. Creating a build up to at least 0.5 above setpoint (Evohome shows 0.5 above setpoint. My own thermometer actually goes up a whole degree). Afterwards, it cools down for about 2 hours, right untill setpoint is reached. Then it starts heating again, building up the 0.5-1.0 overshoot again. So the conclusion is: using zone 2 instead of zone 1 does not improve my setup.

If anyone has other suggestions of things I might try, I'd like to hear it.

[roydonaldson]

Not being one to start flames, but I changed the HR80 in my family room for a new HR92. This is direct on a Honeywell fitting (so no adapter). It now consistently overshoots by about 1.5C. The old HR80 used to keep it bang on. I'm not seeing this in any other zone, so wondering if there is some bug in there somewhere that is causing this. I have a spare HR92 and will create a new zone, add the HR92 to it, copy the schedule over to it and put it in.

Roy.

[Rameses]

Not being one to start flames, but I changed the HR80 in my family room for a new HR92. This is direct on a Honeywell fitting (so no adapter). It now consistently overshoots by about 1.5C. The old HR80 used to keep it bang on. I'm not seeing this in any other zone, so wondering if there is some bug in there somewhere that is causing this. I have a spare HR92 and will create a new zone, add the HR92 to it, copy the schedule over to it and put it in.

Roy.

Roy - it's fine - happy to help objectively.

We need a little more data about this to help though
- How long is this 'overshoot'? How long does it last for? How often?
- How are you creating this 'overshoot'?
- Where are you taking your temp readings from?
- In other zones you mention are they Hr92/Hr80? etc
- How long had the HR92 been in place?

With regards to your 'bug' - we have hard data (from current & live users test sites) demonstrating that the HR92 controls as it should. This has also be backed up by independent 3rd part testing with the AA EUBAC rating. But we are committed to help understand what other factors within your system could be contributing, and if they are 'new' or just newly exposed.