Vaillant EcoTec810 plus Heating Not Working

Joined
24 Feb 2026
Messages
1
Reaction score
0
Country
United Kingdom
Hi newbie to boiler issues here..
I have a problem with my boiler that I've been unable to solve. No indication of failure just happened. I hope you can help me fix it please.

My setup:
Family house, with Vaillant EcoTec810 Plus boiler + one Siemens RDJ10RF thermostat

Context:
Heating was working fine this morning but was set to off during most day. Turned on late afternoon, popped out for an hour and radiators were not hot. Boiler pressure was at 1.2 bar.
I've bled each radiators a small amount. Then pressurised system to 1.5 bar. Then turned heating on from thermostat which did ignite the boiler only temporarily for 5 secs. In pressing the override on the receiver it does not ignite the burner but the boiler clicks and fans start and stay on. I relearned the thermostat which is registering on/off of the boiler but no burner. Pressing the flame button does the same thing also.

The problem:
The hot water system works perfectly, but the heating system is not working at all. The boiler is not igniting but does so fine for hot water. The boiler clicks and fan stays on.

Signals:
The boiler shows status code 5.0 not sure what this means.
If I press the button on the thermostat receiver, the heating SEEMS to try to start, it turns on the icon of the heating pump (although not the burner), and remains in 5.0. There is an arrow symbol. It never starts the burner, and heating doesn't work. No error code is shown at any time.
I'm attaching some pictures for reference.


Can you please help me understand what is happening?
Thanks a lot in advance!!
 

Attachments

  • 1771970662741599619547352092934.jpg
    1771970662741599619547352092934.jpg
    256 KB · Views: 9
  • 1771970700517453174568623652177.jpg
    1771970700517453174568623652177.jpg
    186.1 KB · Views: 7
It looks and sounds like a circulation issue, possibly the diverter motor has failed. Needs a gas safe registered engineer to look at it really
 

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.


Are you a trade or supplier? You can create your listing free at DIYnot Local

 
Back
Top