Shower switches off

[hansPulesh]

Hi all again.....

I posted a topic a while back about my shower unit tripping it's MCB. This issue was fixed by an electrician at the time but now I seemingly have another problem.

It's a Creda 10.5kW shower unit fed by 12m of 10mm twin & earth cable, fed by a 45Amp MCB. The cable runs through the floor void between the ground and 1st floor without any insulation.

I was using the shower this afternoon and it just switched off for no reason at all? The MCB had not tripped and the neon light on the isolator switch was still on as well (as would be expected as the MCB had not tripped).

After leaving the shower switched off for a few hours, I tried switching it on again and it worked again? What could have gone wrong with the shower unit?

Just to add, it's a Creda Advantage 550C

 

[skotl]

Were you using it for longer than usual? Could it have overheated?

 

[hansPulesh]

Just tried it again and the same thing happened - it switches itself off in about 4 minutes. That's deffo not too long?

What could have gone wrong with it?

 

[skotl]

It's not that, then. How about water pressure? Do the taps in the bathroom seem to be giving the same level of pressure that they used to?

Some showers have a "low pressure" warning light - does that come on just before it cuts out?

 

[hansPulesh]

Hi again,

water pressure is the same as before.

The shower unit works for a few minutes and then just stops?

Is there a part which goes wrong in these units?

 

[ban-all-sheds]

The thermal cutout could have gone wrong.

Or it could be working fine, and the heater can has furred up.

Do you have hard water, and how old is the shower?

 

[hansPulesh]

The thermal cutout could have gone wrong.

Or it could be working fine, and the heater can has furred up.

Do you have hard water, and how old is the shower?

Live in London/Essex border and so the water is pretty hard. The shower is approx. 3.5 - 4 years old now.


Is there a fix for these 2 scenarios that you mentioned?

 

[ban-all-sheds]

You could try optimistically replacing the cutout.

IMO the most likely cause of the problem is limescale inside the heater can which stops it from working properly (i.e. stops it from transferring heat to the water properly) so it overheats.

The fix for that is a new heater. Or if you can live without the shower for a while you could try removing the heater and descaling the inside. Problem is you can't get much liquid in there, so it will take a while.