baxi 80 eco nightmare

[joe plumber]

hi there, have a bit of a problem with a baxi 80 eco combi,

i replaced the PCB as this is what i believed to be the initial problem, fired the boiler it ran for half a minute before popping both the 3a fuse in the spur then the 2a quick blow. so i called baxi tech (heat team) and they inform the only things that could pop the fuse are the pump, fan and gas valve. so I check the resistance over the gas valve which is fine then the fan which i s low and they recommend i change so i change the fan only find its doing the same thing! im not ruling out that the pumps jammed but if anyone could highlight anything else i should check or any advice at all id be incredibly grateful.

 

[Blackcatgas]

,,,,,,,,,,

 

[Puddle]

as said usually fan or pump then solenoid or outside controls
solenoid and fan found ok
check no leaking/weeping seals onto flow and divertor micro switches,disconnect pump and check
disconnect room thermostat

 

[Billy Bob Bob]

you need a multimeter to go further,do you own one and know how to use it? if your unsure we will talk you trough it[if i can find find puddle,sent him out the van for some m+fs think he got lost}

 

[Blackcatgas]

you need a multimeter to go further,do you own one and know how to use it? if your unsure we will talk you trough it[if i can find find puddle,sent him out the van for some m+fs think he got lost}

I can see him outside hes smoking a *** and talking to those teenage girls.

 

[joe plumber]

yes i have a multi meter and i can use it, i used it to check the ohms over the gas valve and fan . no external controls fitted it currently has brand new PCB and new fan, itll run for a few seconds before popping the fuse ( the more i think about it the more it sounds like a jammed pump) i just need some fresh ideas to attack it with tomorrow

 

[Billy Bob Bob]

as said usually fan or pump then solenoid or outside controls
solenoid and fan found ok
check no leaking/weeping seals onto flow and divertor micro switches,disconnect pump and check
disconnect room thermostat

as the right honourable gentlemen sir puddle has said dis con the pump rule that out,its not un known for grunies to fail like this,and check ch and dhw flow switches also a fluckey fault that can happen is the main heat exchanger can leak , run down the wiring loom and put h20 in the pcb for this you will need o rings but try the pump first let us know how you get of as this combi is pretty simple and very reliable

 

[LIFES A GAS]

Would have thought the boiler would just bump & bang before cutting out on overheat if the pump was just jammed. Might be wort draining down and removing pump head, wire it up to a plug and lead and see if it runs then, if it blows 3 amp fuse then you can just replace the head.
Martin.

 

[Billy Bob Bob]

Would have thought the boiler would just bump & bang before cutting out on overheat if the pump was just jammed. Might be wort draining down and removing pump head, wire it up to a plug and lead and see if it runs then, if it blows 3 amp fuse then you can just replace the head.
Martin.

not on a 80 eco it has a pump pressure switch

 

[payney1974]

Have you tried disconnecting everything and turn power on see if thats ok then just reconnect one thing at a time and wait until 3 amp blows. Does sound like the windings on the pump but you would think fuse would blow instantly. In the 30 seconds before it blows the fuse does it complete the ignition process?

 

[joe plumber]

ok problem solved!!! on closer inspection today i noticed that the new fan I fitted was caught up on the hood above the heat exchanger which it fixes to thus causing the fuse to blow after a few seconds. i tweaked the hood ever so slightly to allow the fan to spin freely. put it all back together and it went first time!!! i think the lesson here is not to assume a brand new part will work first time

thanks for all your input