Help meeeee! Baxi boiler constantly firing

[JELLYDANCER]

I am completely useless and have no skills so please answer me as if I’m a 7yr old
I have a baxi boiler that has just started constantly firing up and I mean constantly! All night long even though the sender thingy downstairs says it’s off!
Whoosh! .... whoosh ..... whoosh
It’s in my bedroom and driving me crazy. Is it a fault or am I missing something really obvious?

 

[stem]

Much will depend upon the type of heating system you have. When I have seen this fault before, it has occurred on a system that is known as an 'S-Plan' This type of system has motorised valves that look something like this:

Inside the valve is a microswitch that turns the boiler on when the valve is open. The switch can fail so that even when the valve closes, the boiler keeps boiler running. (Although the radiators won't get hot because the valve has closed). However, if your Baxi is a combi boiler, then you can probably ignore this as they don't usually have motorised valves installed in the pipework.

If your "sender thingy downstairs" is a wireless thermostat, then with some makes, it's possible that a neighbour that has the same item that is set to the same 'address code' can operate your heating too, it's rare but does happen. Usually when a wireless thermostat needs new batteries the it fails to switch on, not off. But a change of batteries might be required. If your thermostat isn't battery operated, then you can ignore this bit.

Other than that, it will probably be a case of someone competent perhaps a parent (speaking to a 7 year old here ) checking the wiring with a multimeter to find out where the switched live signal that controls the boiler is actually coming from.

 

[JELLYDANCER]

Ahhh ok I think I need a competent adult to take charge of this situation as I’m out of my depth!
Thank you for the reply x

 

[FiremanT]

TBH, if the BOILER was constantly firing, you would be way too hot,which you did not mention.

If you have whooshing but no heat at innapropriate times, it may be a nackered PCB - a well documented issue. You need a gas Safe RGI

 

[JELLYDANCER]

Oh it is way too hot now! 25.5 deg
Turned all the roads off now and got a guy looking at it tomorrow before I turn into a puddle!

 

[durhamplumber]

Oh it is way too hot now! 25.5 deg
Turned all the roads off now and got a guy looking at it tomorrow before I turn into a puddle!

Why not isolate the electric at the on/off switch?

 

[JELLYDANCER]

I have now because the house is like a sauna!

 

[gas112]

what type of boiler is it ? model name

 

[JELLYDANCER]

Hi there
It’s a Baxi
But the hearing guy is here now so hopefully it will be sorted shortly

 

[gas112]

thats spot on it only narrows it down to 500 or so appliances

 

[JELLYDANCER]

Yeah I know I did warn you I was useless!

 

[FiremanT]

Hi there
It’s a Baxi
But the hearing guy is here now so hopefully it will be sorted shortly

Well ?.....

 

[JELLYDANCER]

Well!!
It seems the boiler thinks a tap is running and asking to feed hot water!
Needs a part so hopefully tomorrow it will be fixed
However!
Now my aqua lisa shower has decided to join in!
No water coming out then it spat scalding water made loads of noise and shut off!!
Bloody great

 

[gas112]

so its a baxi combi 105he or a duotec ?

 

[Deleted member 221031]

I’ll go with Duotec and flow turbine