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armyash

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Hi guys,

After a long day I got sent to have a look at a Potterton Promax System boiler.

All lights off. I checked the fuse spur. No power in or out.

switch at the board had tripped.

Turned back on but fuse would keep blowing.

No leaks visible in boiler, no loose connections that I can see.

The pump at the cylinder has had some leakage. Disconnected the pump and tried the power again. Still trips and blows the fuse.

Any ideas??!!

I have probably missed something but was at the end of a long few days and wasn't exactly focused.

Thanks
 
Your on the right track I believe, disconnect components one by one eg timer, fan etc until it doesnt blow the fuse.
 
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Big fault then from direct connection pump or fan possibly a fault on supply main switch? At worst pcb transformer dead.
 
Got to go and do a flush and commission on a new install first thing so hopefully get to go back and have another look with a clear head.
 
Got to go and do a flush and commission on a new install first thing so hopefully get to go back and have another look with a clear head.
firstly look at components where water and elec can mix you have treid a pump,3 port would be next port of call disconnect lives and neutrals from it however may want to discon boiler first as its easier,2x fast fuses in wiring strip in drop down cover one on live one on neutral remove both and try the trip
 
Hi guys. It was the pump inside the boiler. The bronze pump at the cylinder has been showing signs of leakage so that's what we thought it was.

The pump inside the boiler was only replaced just before christmas and no signs of leaks/damage so we did not suspect that. Will be getting returned to Grundfos as I'm sure they have a longer life expectancy than 3 months.

Thanks for the replies.
 
Hi guys,

After a long day I got sent to have a look at a Potterton Promax System boiler.

All lights off. I checked the fuse spur. No power in or out.

switch at the board had tripped.

Turned back on but fuse would keep blowing.

No leaks visible in boiler, no loose connections that I can see.

The pump at the cylinder has had some leakage. Disconnected the pump and tried the power again. Still trips and blows the fuse.

Any ideas??!!

I have probably missed something but was at the end of a long few days and wasn't exactly focused.

Thanks

One of the worst things you can do is to keep resetting the breaker, the fault should be traced with a meter before applying the power, if the MCB has tripped the first time there was a reason, never reset it even the first time you see it tripped.

Its a bit like a manometer-less electrician testing for a gas leak by sense of smell only.

Glad you found it.
 
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