Boiler keeps tripping main fuse

[Derek P]

I have a grant vortex combi and it keeps tripping the main fuse when the programmer calls for heating.
This has just started, it was working fine before.

Anybody got any thoughts

 

[SJB060685]

Take the front cover off and see if there is water dripping onto CH pump.

 

[ShaunCorbs]

Or water inside the pump power connections be careful do it with the power isolated

 

[SJB060685]

Or water inside the pump power connections be careful do it with the power isolated

Thats what I was implying Shaun 😉

 

[Derek P]

No water going into the pump it is at the top of the boiler, i am going to get the pump checked for a fault, advice from the electrical forum,

Thanks

 

[ShaunCorbs]

When does it trip when the power is on or when there’s demand ?

 

[SJB060685]

So where can you see water leaking from? And where is the water reaching?

 

[Murdoch]

Contributing as a spark in the boiler and wiring there could be many reasons for the "trip" - but as you suggest the fuse / MCB are tripping as well as the MCB then the likelyhood of a live - earth fault is possible.

Is there any water dripping from the boiler?
Valves?
When you say call for heating - are you really running the heating ATM?
Has anybody changed anything - like tried to fit a smart thermostat or programmer?
Have you done any DIY?

Tricky to give much more by the way of advice without seeing the installation first hand tbh

 

[SimonG]

Unplug burner and try again. Will give you an idea if it's the pump or a burner component.

 

[Derek P]

No water leaking.

Trips when demand for heating comes on from the programmer.

Nothing has changed, just started doing it today

Murdoch, what do you mean by ATM, if you mean at the moment the answer is no the heating is switched off, the domestic hot water is on and running fine, it happens when i switch the heating to on then it trips.

Thanks

Regards

 

[SJB060685]

Unplug burner and try again. Will give you an idea if it's the pump or a burner component.

Not a burner problem if hot water is ok mate

 

[Derek P]

Not a burner problem if hot water is ok mate

Not water is fine, just the heating.

Thanks

Regards

 

[SimonG]

Not a burner problem if hot water is ok mate

I'm in daft mode, note to self, read the original post properly 😀

 

[Aquarius]

Not water is fine, just the heating.

Thanks

Regards

Any motorised zone valves?

 

[SJB060685]

You could do with an engineer to run some tests.
I personally would disconnect and make safe the live, neutral and earth to pump and then bring on at programmer again to rule in or out the pump.
If its not the pump then somewhere inside the control panel is the fault, providing of course you only have one heating zone and not multiple as mentioned above.
You really need an engineer to do all this for you.

 

[Murdoch]

No water leaking.

Trips when demand for heating comes on from the programmer.

Nothing has changed, just started doing it today

Murdoch, what do you mean by ATM, if you mean at the moment the answer is no the heating is switched off, the domestic hot water is on and running fine, it happens when i switch the heating to on then it trips.

Thanks

Regards

what type of controller do you have?

 

[Nelder]

I have a grant vortex combi and it keeps tripping the main fuse when the programmer calls for heating.
This has just started, it was working fine before.

Anybody got any thoughts

What fuse is it tripping?

Is it the fuse in the fused connection unit or the MCB (or is it the RCD) in the consumer unit?

 

[Derek P]

Success i think, i disconnected the pump and turned the programmer on and it didn't trip.
Will post again after i get a new one fitted.

Thanks for your help.
[automerge]1596718140[/automerge]
Problem solved, when we went to remove the pump the pump cable was jammed between the front of the flame box and flame box casing, when we took the front off the cable was fried.

Put a new cable in and it's all working now.

Thanks for all your help

Regards