Triton shower buzzing/MCB buzzing?

[chunkymonkey2778]

Hi all, just after a bit of advice on a potential problem I've just come across today please?

I have a Triton Enrich 8.5kw electric shower, my son was using it today and I just happened to walk by the fuse board as the shower was on and it was making a substantial buzzing noise from the 32A MCB.

If I push upward on the MCB the buzzing stops.

Once the shower had dried out I've had the front of it off to see if there's anything obvious but couldn't see anything.

There is also a buzzing from the shower unit now, but the MCB is a lot quieter.

If I push upward on the MCB so it goes quiet I can hear the buzzing from the shower upstairs.

The shower is probably about 8 years old so is it likely I might need a new one, should I try an MCB first or am I likely to have further problems that I need an electrician for?

 

[flameport]

8.5kW is about 35 amps, more than the 32A MCB is designed for.

 

[chunkymonkey2778]

So would it be worth me trying a 40A MCB?

I do remember something about when the new shower was fitted it was a slightly higher rating than before, maybe the old one was 7.5kw.

A plumber fitted the shower, but I asked an electrician friend of mine about it and he said it might 'nuisance trip' but should be fine?

 

[EFLImpudence]

So would it be worth me trying a 40A MCB?

Yes and no.

You might (unlikely) only have 4mm² cable which has a current-carrying-capacity of 37A - method C - so no.

Having said that, you have been using the shower which draws 35.4A @ 240V and is unlikely to cause an overload so it won't make any difference to anything except save the MCB overheating, so yes.

But - then everyone will tell you it is not compliant.

but I asked an electrician friend of mine about it and he said it might 'nuisance trip' but should be fine?

Has it ever nuisance tripped?

 

[Taylortwocities]

The great thing about the “nuisance” trip is that it doesn’t happen right away. Usually a few minutes into the shower.
This new feature will encourage everyone to keep their showers short, thus saving you £££

 

[chunkymonkey2778]

It's never tripped out or misbehaved at all until yesterday, sometimes being used three times a day, they're not short showers either.

It's not tripped out yet just makes that buzzing that comes and goes dependant on if the MCB is being pushed up or not.

Is there a way to find out what wiring I have at all please? The house was built in 2003 if that makes a difference regulations wise etc.

 

[pete01]

I would change the 32 amp to another 32 amp, it's on the brink and it finally worn out, cable size dependant a 40 amp would be a better solution.

 

[chunkymonkey2778]

If I took the cover back off the shower and took a photo of the wiring to it would that help knowing what size cable I have or difficult to say from a photo?

 

[Taylortwocities]

Have good careful look underneath the MCB. Main switch off.
Make sure the busbar is properly located snd securely clamped by the MCB screw at the bottom.

 

[EFLImpudence]

I would change the 32 amp to another 32 amp, it's on the brink and it finally worn out, cable size dependant a 40 amp would be a better solution.

But, as I said, a 40A won't make any difference apart from not over-heating a 32A MCB - so would be better.

The cable and the current drawn by the shower won't change.

 

[chunkymonkey2778]

 

[chunkymonkey2778]

Is the above post relevant at all?

 

[pete01]

But, as I said, a 40A won't make any difference apart from not over-heating a 32A MCB - so would be better.

The cable and the current drawn by the shower won't change.

Not over heating is a big difference to me.

 

[Taylortwocities]

Is the above post relevant at all?

No, and it is largely wrong and/or misleading.

 

[chunkymonkey2778]

The shower is the second single MCB from the left.

So 6mm wiring?

Worth trying a 40A as the screws all seem tight?