Shower isolation ... again

[SUNRAY]

Just come off the phone with a colleague following a call out he attended.

Small block of 6 flats on 2 levels, ground floor tenant called landlord to say water coming through ceiling and upstairs tenant works late shifts and often runs into all night. Landlord arrived and turned off water to whole block and CU which stopped the shower running and called Emergency plumber/electrician as stairway lighting fed from that flat. There had been a powercut around 5pm.

Colleague turned water back on and directed shower head away from cubical door then turned CU back on, turned shower knob 2 clicks which happened to be from 'LOW' to 'OFF'. Tenant returned home to find landlord and my colleague. He insists he uses it on 'HIGH' and turned it one click to off but the assumption is he turned it the wrong way to 'LOW'

This is typical of Triton style although some are high on left and cold on right (like mine), I don't know which version is subject so I'll go with this one:

So assumed he turned it from right to down instead of right to up.

Apparently landlord went into the riot act for not pulling the isolator switch everytime as appears in the rental agreement.

Sorry but I've said it before and I still maintain it is a good habit to isolate these units when not in use.

 

[Hobobanobo]

The isolator switch pulled in my shower just means it runs cold. The water would still run if I left it switched to low (I'm surprised he didn't notice it was on when he finished showering. Odd)

 

[SUNRAY]

I'm a little surprised your water runs without power as I have not seen an electric shower heater like that for a very long time, these days they usually have an electric valve to start the water then a pressure differential switch powers the heater. This happened during a power cut.

 

[Adam_151]

For some reason gainsbrough stick in my head as doing this. I've also known other makes to do it when the microswitch that controls the solenoid valve for the water suffers condensation and starts tracking across*

*I've got a steam cleaner where the steam valve is opened by a mechnical linkage which pushes a pin in where the output hose attaches to the machine, which closes two small microswitches in series to power the steam valve. It seems that when O rings on the steam connetcion fail and you get a bit of steam leaking out at the point of connection, eventually it results in both microswitches tracking across. I guess the manufacturer knew that sort of thing was a possibily, hence the two in series, but clearly its not sufficinet in all situations

 

[SUNRAY]

I'm certainly aware of Gainsbrough and yes they were a bit of a market leader IIRC, our first 2 were 6KW and 7.2KW. Very basic: tap on the feed pipe, PRV in the form of a rubber sleeve over a hole in the inlet pipe, pressure switch, resetable thermal trip and copper vessel containing the element. However that was 50 years ago.

I haven't encountered that set-up for at least 30 years and the very small selection of Gainsbrough I have seen in recent times (Not many as they are more expensive than others) have all included an inlet valve.
I'm not saying all modern shower heaters follow the same format as I don't have experience of every model, I simply haven't encountered them without the valve.