Triton Opal shower cuts out/ trips RCD.

[reado100]

Hi, My triton opal shower keeps cutting out tripping the RCD. I pull the
isolation switch, the light comes on so no problems there. When i turn the shower on (heated setting) it trips the RCD imediately after 1 second. If i turn the shower on cold, it works fine however. I removed the hose to make sure a blockage wasn't the problem. Any ideas?

 

[sparkyspike]

Yes, it sounds like the immersion heater in the shower unit is knackered - i.e. it is leaking current because it is corroded. How old is it?

 

[reado100]

i'm not sure how old it is but it was here when i moved in 3 years ago, i suspect about 4 years old.

i've seen the spares are quite pricey maybe cheapier just to get a new shower. Are there any that have the same fitments as this one and could i fit it myself?

 

[flameport]

Triton still make the Opal (Opal 2 now), so you could just replace the whole unit.
Replacing the heater in the old one is not likely to be much cheaper, and who knows what other parts might fail next week/month?

Replacing the shower is not notifiable work, so you could do this yourself.

 

[reado100]

I've manage dto source a 6 month old Opal 10.5kw so it will be a simple replacement. The thing is i noticed the MCB for the shower says "B32" on it, as does the sockets and the cooker one with water heater one says "B16". I'm assuming B32 means its a 32amp breaker. i was under the impression that a 10.5kw shower should have a 45amp breaker. If this is so how did it work at all for the last 3 years? One thing is, it did always trip the MCB if the ran for over 10 mins though, confused?

 

[luminaire]

Strickly speaking you should have a 50A MCB for 10.5kW as we now base our calculations on 230v.
You would also need to check on the size of cable used as 6mm² would definitely be too small.
You really need to get hold of an electrician to have a look at the whole situation as it sounds as though the MCB for your cooker may also need to be replaced and again possibly rewired.

 

[bernardgreen]

Breakers have a dual tripping mechanism. A slow response thermal trip that allows short time overloads that are not much more than the rated trip value and a fast magnetic trip that reacts almost instantly when the over load is several times the rated trip value.

So when the shower is on for 10 mins the approx 8 amps over load is warming up the thermal trip up to its tripping temperature.

 

[Spark123]

Strickly speaking you should have a 50A MCB for 10.5kW as we now base our calculations on 230v.

You need to look at the shower unit to see what voltage the rating is at, it may be 10.5kw @240v and 9.6kw @230v, they stick the former on the box because a 10.5kw shower sounds better than a 9.6kw shower.