Problems with Vaillant thermostat

[Indigosky]

I posted a while ago about changing batteries in the thing, and was helped here (30 seconds max to avoid losing settings). Since then got another problem. Went away for a week and turned the boiler off, from the thermostat, while away. This was principally because I've had issues with the thermostat in the past and didn't want any random heating coming on while we were away.
So since coming back 3 days ago, the rads are heating up randomly, when it is not cold enough for the heating to kick in, and it seems the boiler has lost connection with the thermostat. Spoke to the engineer who installed it, (in March 2018) and he claimed it was our Wifi signal interfering with the stat. Can anyone confirm that this is a thing? I spoke to Vaillant homeowners technical helpline, and he said he'd never come across wifi interfering with boiler/stat comms. He suggested turning boiler and stat off together, then turn back on together, to re-establish the connection.
The thermostat normally (VRT 350f )sits on the wall, about 9 ft from the Wifi router. It has worked OK for 18mths, only had probs just after installation (same thing, rads heating up randomly) whereupon the installer put in a new thermostat, which worked OK until a few weeks ago. Can anyone shed any light? Could I have the thermostat wired into the boiler would this help?

 

[Brambles]

Most unlikely to be interference from your WiFi transmitter - the frequencies are very widely spaced apart ( WiFi 2.5GHz or 5GHz against your thermostat communicating (RF) at 0.85GHz). Interference from another wireless thermostat with a separation frequency of less than 0.025GHz or electrical interference from an adjacent power supply ( within 0.6m) or shielding from a large metallic object are more likely source(s) of interference.

Check that the batteries in the remote thermostat are not low. Then check that the and receiver and thermostat are are communicating. If not, then clear and rebind the units.

If the receiver unit was set up properly, if it fails to communicate with the remote thermostat it will not call for heat unless overridden by the frost protection settings.

If all the above fail, then you will probably need a GSR engineer to access the receiver - unless it has been retrofitted, it will be within the room sealed part of the boiler housing.

Once you have triggered that option, fix the problem once and for all by:

Using my preferred ( cheaper) solution to replace the Valiant wireless control with an externally ( external to the boiler) Honeywell ( or Drayton, Hive, Nest el al) system. Full replacement of the Valiant controller with a like for like original (OEM) is an expensive option.

Hard wiring is also an option, but again ( for a Valiant) ) you will need a GSR to access the interface point.

 

[Scott_D]

Not sure if they still do but vaillant use to give a 2 year warranty on controls

 

[Indigosky]

Brambles, thank you so much for your very helpful reply, what you said about Wifi confirms what I have read online, ie that it is very unlikely to be Wifi interference causing the problem as the frequencies are different. I saw mentioned online the fact that the Vaillant boiler has a drop down metal door covering the front of it where the controls are housed - can be an issue - does this count as a "large metallic object"? you would think the designers would take this into account.
I changed the batteries in the thermostat a few weeks ago. If the problem persists, I will definitely take up one of your suggestions, of getting a Honeywell or other thermostat or using hard wiring. Thanks again.

scott-d - I am not sure if this is the case but will find out. Tbh, I am not at all sure that I want another Vaillant controller - I looked my particular one up on Amazon and it has absolutely abysmal reviews. I would rather cut my losses and go for another option even if I have to pay for it.

 

[Brambles]

In my experience, if properly fitted and configured Vaillant controls are fine. The issue is the cost of parts / replacements when they do have problems.

If the issue is reception an externally fitted received is a better option - it is a DIY job to reposition it for optimum performance

 

[Indigosky]

Thank you Brambles, - excuse my ignorance - do you mean a receiver removed from the innards of the boiler and repositioned ?

 

[Brambles]

Yes, but it is unlikely that you can fit the Vaillant one externally. I don’t know your boiler model so I cannot confirm or otherwise.

Hence use a non OEM one

 

[Kerry d]

How do you link your control panel to your boiler receiver. My boiler was working fine, until I took the batteries out to change them and now can not get them to link back up?

 

[Indigosky]

How do you link your control panel to your boiler receiver. My boiler was working fine, until I took the batteries out to change them and now can not get them to link back up?

I phoned Vaillant's helpline with this issue and they told me to turn the boiler off and remove the batteries from thermostat at the same time, then put them back in and turn boiler on at the same time, and it was all OK after that, and continued to be until we moved house in June of 2020.

 

[moonlight]

The receiver for the stat is now recommended to be fitted externally as the boiler front cover is metal and also cause a problem. Its not a difficult task to move. Do you still have the blanking plate for the boiler? your gas engineer should be able to mount this for you.

 

[Kerry d]

I phoned Vaillant's helpline with this issue and they told me to turn the boiler off and remove the batteries from thermostat at the same time, then put them back in and turn boiler on at the same time, and it was all OK after that, and continued to be until we moved house in June of 2020.

Hello, I have tried that and it still does not work. There is no green light on the boiler, so it will not connect.

 

[Angie Maycock]

How do you take the batteries out of the free standing remote control? There seems to be a very small round type screw , but we can’t seem to move it. Any ideas

 

[Aquarius]

Underneath iirc.

 

[T29MES]

Hi all looking online for a resolution to problems with our Vaillant VRT 350f and have come across your chat on this forum.
Our one is doing the same thing, randomly putting the heating on in on days when it doesn't need to be. It has worked fine for over 5 years and now is doing this.
May I ask did you solve this issue?

 

[Deleted member 120897]

Hi all looking online for a resolution to problems with our Vaillant VRT 350f and have come across your chat on this forum.
Our one is doing the same thing, randomly putting the heating on in on days when it doesn't need to be. It has worked fine for over 5 years and now is doing this.
May I ask did you solve this issue?

Is it the thermostat doing this, or do you have a mechanical timeclock as well? Could also be the diverter valve sending hot water around the heating circuit, especially if you have the pre-heat function turned on.

 

[TessaConfused]

I am trying to remove my controller (VRT 350) as I have had enough of the problems - can anyone tell me how to decommission it from the boiler so my Hive can take over? TIA

 

[Deleted member 120897]

I am trying to remove my controller (VRT 350) as I have had enough of the problems - can anyone tell me how to decommission it from the boiler so my Hive can take over? TIA

Is the VRT350 wired or wireless?

 

[Worthy]

I am trying to remove my controller (VRT 350) as I have had enough of the problems - can anyone tell me how to decommission it from the boiler so my Hive can take over? TIA

Hi did you manage to decommission it l am trying to do the same thing