Wiser Hub not telling Boiler to fire when radiators calling for heat

[csaunders72]

Hello,

We installed our Wiser system about 1 year ago with 5 smart TRVs. About 3 months ago we switched all our other radiators to smart TRVs. Apart a few glitches it was working well.

Recently, however, we are experiencing a growing number of issues more and more often. Of particular concern at the moment is that the boiler is often not fired up even when many radiators are calling for heat.

A curious incident happened on Friday 10th in the morning when all radiators were warming up nicely but then they all started cooling down even though they hadn't reached target temperature. I've uploaded logs from the Hub so, hopefully, you can see that.

It is worth noting that one reason I had Wiser installed is that I am disabled, with very limited mobility, so I can't turn radiators on or off manually or check what the boiler is doing. My condition also means I am very sensitive to cold so I need a reliable and controllable heating system.

I hope someone can help in this matter.

Cheers,

Colin

[PhilHornby]

Schneider/Drayton support are not currently frequenting this forum - it's just other users like yourself.

You could raise a fault at: https://schneider-electric.zendesk.com/hc/en-gb/requests/new 

or

https://www.draytoncontrols.co.uk/contact-us (Not sure what the difference is, but it also has a phone no. to call).

The effect you're seeing might just be normal operation (for example, in "ECO" mode, devices are turned off before the end of scheduled times).

IMHO, if you need room temperatures to be anything like accurate, you need Roomstats, rather than just relying on iTRVS. The latter are affected by the heat of the radiator and compensation has to be applied - they're in what is probably the worst location in the room for performing this function.

[csaunders72]

Thanks for your response.

Having re-read my post I now realise it was not totally clear what I was trying to describe. I'll try again ...

I'm aware of having to set the iTRVs to a higher temperature than what we want the room temperature to be. As you said, being right next to the radiator is bound to affect the performance. And thanks for the link to their support desk - I couldn't find that the other day.

The iTRVs were, on the whole, calling for heat and getting the rooms up to temperature set on the app. So all was good ... until Friday this week. I did wonder if it had gone into some ECO mode but the app doesn't show that. 

So since Friday, it's been behaving strangely. It's probably worth mentioning that on Thursday we had some glitches on our house electricity supply. Caused lights to flicker but my computer monitors didn't turn off.

Here are some screenshots from the App showing the behaviour of the iTRV in my home office.

Friday:

• Starts warming up fine in the morning
• About 7:30, before reaching target, the temperature starts going down
• Note - most of the iTRVs did the same thing at that time
• We tried various things - reboot Hub, boost all, turn off hot water, just turn on this one iTRV etc etc
• And eventually it warms up again in the afternoon

 

Saturday:

• Similar drop off in the morning at 6:30
• And again in the middle of the day
• Again, tried a few things - reboot hub, take batteries out/in of some iTRVs to rejoin system, etc etc 
• Then, later on, it behaves properly

Sunday:

• Today it's in a good mood 🙂

 

Has anyone experienced this kind of behaviour?

Could the power glitches have damaged or confused the Hub?

Any responses much appreciated.

Cheers

Colin

[Ch0ngma]

How did you extract logs from the Hub? I've experienced this a few of times over the last year, the most recent being a couple of weeks ago and just thought that it was more an issue with my install. Mine seems to fail in the afternoon, but the next morning everything is back to normal. (Also causes a problem with Insights as it thinks you've been burning extra fuel).

Additionally a few days last October, the boiler was staying on even though there was no request for heating / hot water...

[csaunders72]

Hi,

Oh, the bit about the logs was referring to the function in the app to upload them. I presume that's to a Schneider/Drayton server somewhere.

Update: The system has continued to stop providing heat every so often with no obvious pattern as to when it happens. Our plumber came out to have a look but, obviously, it was all working fine when he was here. He said the boiler could be shutting down if an airlock made it to the boiler but he didn't think there was much air in the heating circuit. We have found that we can usually get the system going again by putting it in Away Mode for 15 minutes or so and when we cancel that it wakes up. If that doesn't work then power-cycling the Hub usually does.

It all seems to suggest it is the Hub playing up. When heating or hot water go live I can hear a click from the Hub which suggests it has relays to control those circuits. Could they have been damaged by the power supply glitches we had last week?

Cheers,

[WiseruserUK]

Did you get this resolved @csaunders72 ? I have the same issue, intermittent but been getting worse. Now power cycling doesn't fix it. Switching on hot water does make boiler respond to call for heat though. Now deteriorated to the point I only get heating if the hot water is on.

I have a greenstar 24i system boiler.

I've raised a support ticket but seeing this thread makes me think it's a common fault with the hub.

[Fozzie1960]

This is something I noticed my system doing this before Christmas. I’ve had Wiser for over five years ago and this problem is something that started recently. Insights showed my heating being on for 12 hours on one the mild days before Christmas.

[StewartT]

The fact that we are guessing because the support function isn't there or doesn't care is a bit sad as this product offers so much. 

These symptoms could be down to the hub noticing that the stats are controlling to very near the configured set point and maybe making the assumption that the boiler pump will run on with "free" heat after the boiler has been commanded off. Once that completes the stats remain in an unchanged ON position until the hub decides that the boiler should be started. The reporting may need tweaked to show only boiler ON time rather than stat OPEN time. Just a theory.

As moaned about before technical support for this product is below what it should be and it is certainly eroding my enthusiasm to maintain an active interest and forum contribution level.

[Ch0ngma]

Managed to have our issue resolved. The actual problem was with the Honeywell Powerhead rather than anything on the DW side. The Powerhead was failing to open the valve so hot water could not circulate around the central heating. There’s a safety in the boiler to prevent excessive water heating so even though the Hub was calling for heat, the boiler wasn’t firing. Replaced the Powerhead last spring and everything has been fine since (touch wood...)

[nathanrdedman]

Hi,

I've just started suffering with this issue too (HW fine, boiler not firing despite iTRVs showing heat demand), with daily hub power cycling to get it up and running again.

Given these are being reported more frequently recently, I wonder if it's a software issue, or a hardware issue that's been caused by the latest firmware?

Really stumped, since HW is fine. Perhaps one of the switching relays is frazzled (and why de-energising via power cycling resets it)?

I'm going to try and pick up a second hand two channel hub to try and do some testing.

[WiseruserUK]

@Ch0ngma , thank you for advising your solution (what model boiler do you have), I do wonder whether the issue is with the boiler or relay, power cycling doesn't fix it for me anymore, only way to get heating is to put hot water on but once that's up to temperature, the heating seems to stop. That would probably rule out the relay. When I switch on hot water I hear the relay in the wallplate and in the electrical box click but when I turn on heating I don't hear clicking in the electrical box.

The fact it has been a deterioration issue rather than just stopped working fully one day makes me think hardware rather than firmware.

Ticket is moving slower than I'd like but I've generally had good experience with the help support, get lots of email responses until issues are concluded.

[Rich3]

Me too on this issue. Took me 24 hours to notice but after years of working correctly, the radiators only heat up now when the hot water is on. The heat report demonstrates perfectly.

[WiseruserUK]

Schneider support suggested it's a valve issue.

Have got a gas engineer coming out to look but talking through over the phone, they think it is the zone/port control valve, which is the same issue Ch0ngma had, the Honeywell Power head. Photo below of the silver box, apparently when everything is off, you shouldn't be able to move the lever on the top but I could for the heating box, not for the HW box

[Ch0ngma]

@WiseruserUK 

We have a Worcester Bosch Greenstar RI Compact, installed in 2021, just before we had DW put in.

All the powerheads / hot water tanks are probably 20+ yrs old, so can imagine that the valves being asked to open and close many times per day, rather than once or twice under the previous schedule, it’s contributed to them giving up.

[Rich3]

Just to confirm, issue resolved by replacing actuator on three port valve.

[brucezubaa]

I've raised a support ticket but seeing this thread makes me think it's a common fault with the hub.

[brucezubaa]

I've raised a support ticket but seeing this thread makes me think it's a common fault with the hub.

[WiseruserUK]

It looks like everyone who has experienced this has found that it is hardware on the plumbing side, not related to the wiser kit.

As @Ch0ngma suggests, the more regular on-off cycling that arises from the wiser functionality (I.e. each rad can switch heating on when needed instead of one centrally located thermostat) likely accelerates wear out on the power head. Is ~£100 part plus an hour of a boiler engineer to replace, though is only a few screws and wiring so could potentially be done by competent diyer.

[nathanrdedman]

A £35 two port valve head and 5 wires later and the heating is back in business. A system hardware fault!

[csaunders72]

Hi,

Since my last post in Feb there have been some developments here too. Once we started using the heating again the autumn it was clear the problem was still there. At the end of Sep I got our plumber out to check the inline valve for HW and indeed it was a bit stiff. He also noticed the 3 way diverter valve was feeling stiff even though it was a fairly recent replacement. So, he changed those two and the system seemed to work ok for a bit but then started deteriorating again.

Then I happened to be mention the trouble we'd been having to a friend and, just by coincidence, he had a friend who used to make the Worcestor boilers so he got in touch with him. His friend said some of those boilers, made during a certain period, would develop intermittent faults due to dodgy soldering on the circuit board. So, he instructed my friend, who is an electrical engineer, how to fit some test lamps to check if that was the problem. It wasn't.

Previously I had noticed that the heating circuit pump wasn't sounding great and the plumber did say it probably wasn't running at 100% any more. Over time I noticed that the sound the pump was making seemed to loosely correlate to how well the radiators were warming up. I also found that going into Away Mode in the app to cancel all demand for heat and giving the pump a short rest would often be enough to get it going again. Usually no need to power cycle the hub, although, as my plumber explained, that would give the pump more of a shock.

It's been really bad recently but thankfully our plumber is coming back this week to change the pump, also a fairly recent replacement. I'll try to remember to post an update once it's done.

[Pjspjs]

I now have the same problem but boiler not being called at all. When the system turns on Hot Water the boiler is started and works fine (even turning off when Hot Tank temperature met). But when radiators show as calling for heat there is not request for the boiler and pump to run. We now have a cold house.

The problem occurred occasionally recently but cleared when control unit shut down and restarted. We do have the occasional power cut. We were away last week and we had another long power cut and when we returned we had no heating although the control did work the hot water function.

[Tomtrice]

We have for the last week had identical issues as described above. Generally things work earlier in the day then get worse. Radiators are calling for heat but boiler doesn’t fire up and start pumping. You can hear the radiator valves open etc so that’s not the issue. Have British Gas home care due round in a few hours so let’s see what they say. I’m hoping they don’t just say it’s an issue with your app…

[Tomtrice]

So, engineer came. He was very good and we worked out it was the same as above. Valve actuator was replaced and now all good. 

[Fozzie1960]

My motorised valve has been changed and the problem still exists. Heating engineer checked the boiler while he was here and could not find anything wrong. It’s very difficult to replicate the issue. One thing I have noticed is it never happens first thing in the morning. Anyway, the engineer is coming back next week to test the boiler again. Logic says it must be the valve or boiler at fault. However, given there are so many on here reporting the same issue it makes you wonder. 

[csaunders72]

Finally remembered to do an update. Plumber came back and replaced the pump. He also noticed that the fairly new 3 way valve was jammed - the little thing inside had snapped off, something he'd never seen before. He also flushed out the heating circuit and said it had had LOTS of gunk in it. That would explain problems with flow round the circuit and, maybe, the valves wearing out.

It was, thankfully, much better after that. The system did "stall" a few times but the new pump has an LED indicator on it which reported a flow problem. Thankfully, we worked out that was just an airlock (*) in the pump and when we shut everything down we could actually hear the air making it's way up through the pump. 

(*) We've got an old house with a heating circuit that resembles a roller coaster so airlocks are often an issue.

[Stevers]

We have exactly this problem (hot water but no central heating).  The Wiser system was installed two years ago and has performed well until now.   Initially we thought the hot water was only intermittent, and suspicion fell on the boiler (me) and three way valve (plumber).   Both seemed fine, but our excellent plumber was unable to do further diagnostics as our HubR was proving impossible to connect with.  We changed the HubR to a dedicated 2.4Ghz wi-fi network served by one Router, and although that has helped it's not infallible. 

This morning the Wiser App could connect, and I could see radiators calling for heat to warm a couple of rooms for my mother who we care for.  Having found a wiring diagram I had a look in the Wiring Centre - it's a 100% ACL Drayton install from 1997 - connections also on a label in the lid!   When I turn up the cylinder thermostat the boiler and pump fire up, and I see 240V on the terminal 10 of the Wiring Centre, but although heat is clearly being called for, there is 0V on terminal 9. Terminal 10 is 'HW on' and 9 is 'CH On' from the controller/HubR.  Since then the HubR has dropped out again - red light and no connection to the Wiser App.  

I think in this case our HubR is likely to be at fault and I have raised a support call with Schreiber Electric asking if there are any diagnostics that I could run to confirm the problem.

[Stevers]

Once I realised that the wiring in the Wiring Centre was nothing like the Drayton label in the lid, I traced the signal from the controller through the wiring centre to the white wire of the Three Way Valve.  That had 240V on it, but the valve head was resolutely in Hot Water only mode.   The Synchron motor had been replaced, but testing hadn't been possible as we couldn't connect to the HubR.  Clearly now the Three Way Valve was at fault. 

Our previous Three Way Valve had seized, and the previous (working) head was stored in our basement.  Fitting that original head to the current body has restored our central heating.  When fault finding I hadn't appreciated that the Three Way Valve had a role in starting the boiler and pump - something to remember for next time!