Baxi combi 105e new pcb now what?????

[bulldogger]

Hi Peeps wondering if anyone can help?

i've got a Baxi combi 105e that went on the blink yesterday, no hot water or central heating.
It flashed the 50'c led fault which is the fan or a blocked flue, checked everything over and no blockage and the fans fine.
Came to the conclusion it was the pcb.
Replaced the pcb today and i now have hot water but theres absolutely no sign of life from the central heating??? has anyone any idea's?
Could it be a fault on the new pcb?


The timer switch seems to be fine...

Cheers..

 

[ollski]

programmer, thermostat, wiring. Where does the mains voltage end its journey?

 

[nickso]

any lights flashing when the heating demand is on?

 

[bulldogger]

any lights flashing when the heating demand is on?

Not a thing!

 

[ChrisR]

Is it an "instant" model, and which pcb did you put in? Some manuals are wrong.

 

[namsag]

That fault light also means it could be the sensor fitted by the plate heat exchanger is faulty.

 

[bulldogger]

Is it an "instant" model, and which pcb did you put in? Some manuals are wrong.

its not the instant model. i replaced the pcb 248074 with the new model 5112380

 

[ollski]

Bulldogger where does the 240v call for heat end?, does it get out of the programmer, into and out of the room stat, back to the boiler etc?. The fact the clock goes round and keeps time don't mean the switches on it call for heat when they should etc.

Is the switch on for heating and hot water?....I've done it.

 

[bulldogger]

Thanks for the help guys..

After a little gentle persuasion the guy behind the counter swapped the one i bought yesterday!

ive just installed it and hay presto i have hot watter & central heating