Vaillant 831- help required

[su C]

Hi, I have a vailant 831 boiler and sylus thermostat. This boiler is the one with the timer.

1. When I increase the temperature above the room temperature on the thermostat I can see the green light turning up on the reciever.
- this is to confirm that the pairing between the thermostat and reciever is fine.

2. When I turn the knob of my boiler to the radiator, it switches on the heating irrespective of what the temperature is on the thermostat.
Even if the temperature set on thermostat is set to lower than the room temperature, I see the boiler starts to heat up the radiator.

Am I doing something wrong or would you suggest me to try out anything.

Thanks for your help!

 

[fixitflav]

Has it worked OK in the past, or is it a new system, or have you just moved in, or what?

 

[su C]

Has it worked OK in the past, or is it a new system, or have you just moved in, or what?

I have just moved in.

 

[fixitflav]

I have just moved in.

Sounds like it's wired wrong, but but needs on-site investigation. In case you haven't got it, User Manual here Ecotec

 

[su C]

Thank you. But could figure out the issue. The 24v rt loop was connected.

 

[fixitflav]

Thank you. But could figure out the issue. The 24v rt loop was connected.

Sorry, don't understand. Do you mean you couldn't figure it out?
In a quick look at the Installation Instructions, as well as the User Manual I didn't see anything about 24v so you're ahead of me there.
I don't know much about these boilers, I was hoping the history I asked for would help somebody on here diagnose the problem. History is often important but rarely mentioned by posters unless asked for!

 

[Deleted member 317380]

24v link would have been my 1st port of call for the fault you describe. Removing the cover on that particular boiler forms part of the combustion circuit and should be checked for safety afterwards.