baxi main 24 he , easy fault lol, i hope !!!!!

[martindiy]

had a roblem in the last 2 days with long time for hot/w to heat up goes cold then heats up and then its ok, hi i have just checked the air switch with a new one, and checked the thermo switch all,ok, what happening is turn the hot/w tap on and it will not spin the fan motor, then has flame failure flashing ,with the tap still on it resets it self and runs fine, it seems to be the first time u turn tap on it goes to flame failure, any ideas guys thanks

 

[corgiman]

sounds like a partially blocked Domestic hot water heat exchanger to me

 

[martindiy]

wouldn't that then happen every time when running, not just on initial demand ??

 

[gasafengineer]

Partially seized fan.

 

[martindiy]

no checked that, it get s no power on first demand,by the way the boiler is 3 years old ,

 

[twgas]

I would have thought it would need a manual reset if it's gone to flame failure.

 

[martindiy]

i leave it running about 20 secs then it fires the fan up and then ignites and runs ok,

 

[Agile]

Depending on exact model you may have a system flow switch which prooves the pump is running.

If so then see if it operates immediately the pump starts. Thats if the pump starts when the DHW flow starts!

Tony

 

[martindiy]

its a main 24he combi

 

[martindiy]

hi guys thanks for your input, i have noticed today if i wait for it to go into flame failure, then lift the 3 way valve with the micro switch on the top of it up, it all kicks into llfe, what is this for ? would it be the diagpram inside ? thanks

 

[Agile]

Most unlikely.

Much more likely to be dirt in the system or a weak pump or dirt in the pump impeller!

Tony

 

[martindiy]

ok so know ones got a clue then, thanks anyway

 

[martindiy]

i have removed the inlet/return manifold, and stripped it down, i found the plastic venturi broken and wedged in the outlet port, got to try and find one to buy next, i hope this is the problem

 

[martindiy]

hi i have changed the veturi and it woked fine, but acashonaly it will shut down, and i can see the micro swith on the top of the diverter block not lifting the micro switch enough, maybe its the primary heat exchanger, i have a new one but its a bit bigger, its like not enough presure to lift the pin, i have replaced the small diaphram on the top, and ideas please help

 

[adlplumbing]

you should get serived know