Recent content by sam smith

I just noticed the pump had come on randomly yesterday so checked the S and D values. This morning after the radiators were timed to turn off at 9.00am I came downstairs and the pump was running until 9.30am. Is it normal to have the circulation pump running for so long after a heating demand...

The temperature on the boiler display then dropped to 18 c and the pump over run stopped. The room stat is reading 19c and now so is the boiler

@The831Bunny Just to give u an update. The pump has come on the S code is S7 and the D 9 value is 10?

Hi, ok sure thing. I will run through that sequence once the pump comes on again. I do know that when it came on before without any demand the code was S7 which I believe is for pump overrun. I have not recorded the D9 value but will do this once it comes/plays up again. Many thanks

Thats the boiler

Ok so the pump has come on again theres no demand for hot water or heat (timers are off for each) but the radiator symbol is flashing and the pump is on, the reading on the room stat is shown too. Is this the same “fault” or is this happening as the boiler thinks theres too much “heat” in the...

I will see if I can find the post about a similar problem to what I had (pump coming on - without any heating/hot water demand) and you can let me know what you think as in that case it happened to be a faulty port valve

Hi @The831Bunny Thanks for this. I see what you mean about how the weather compensator will affect the boiler in the warm weather we are having. As the previous person mentioned to check the port valve, I checked both and noticed when i pushed the lever of the top valve to its opposite...

Hi, thanks for that. I would have to look up what you mean by ebus but will certainly look at the D values and update you. Thanks to both of you guys

Hello The831Bunny, I will check the D.9 diagnostic code and see what is says. As suggested by CBW I physically checked both port valves and the one above also has resistance, although now that I have pushed the lever to the other side, it is in effect much looser, I am guessing this is...

I can possibly get someone to check the terminals for output etc but they would need to know what to look for etc. the lower valve definately had resistance but not checked the top one. I will do when I get home and update

Hi @CBW, Thanks for your prompt reply. Yes pump overrun most likely does come via PCB but I read on a previous thread a couple of times that it could be a faulty micro switch on a port valve sending false info to the boiler thereby sending into circulation/over run mode. Im not sure how I would...

Hello Folks and Especially those that are averse to Vaillant prooblems I have an Ecotec plus 637 systems boiler not sure if its S or Y plan but will poost pictures. Theres a wireless room stat in same room and a Valliant control center too. All has been running fine for absolutely ages until...