This question is regarding Triton T80si/T90z Thermal Cut-out (TCO) (From 2011) - 22012680

mad hot or cold

The shower is either very hot or cold, it runs cold on cold setting turn it up, until you hear the heater click in then it runs very hot no matter what setting you have it on
Asked 8 years ago by John
The things to check first are:

1 That the main valve coming into your house is fully open.

2 Then check that the valve on the line to the shower is fully open.

If these valves are not fully open then there may not be enough water getting to your shower to cool it properly the overheat safety device will turn the power off until it cools Then it all starts again



Make sure that the shower head is clean and clear, that the hose isn’t kinked (this can happen just behind the hand set where it is difficult to see) also check the inside of the hose although it can look OK on the outside it could have collapsed internally

The other possibility is a faulty flow/stabilizer valve not allowing the correct amount of water into the shower.

A rough check is to remove the shower head turn temperature control to fully hot the water coming out of the hose should be a bit more than a dribble then turn to fully cold and it should be coming out at full flow.

If there is not much difference between the two then you could have a faulty flow valve.

Carry out this check after you check the inlet valves.

Also as it is a Triton have a look at the outlet TCO

The outlet Thermal Cut Out this is a black disk with two wires going to it and it is mounted on the out let pipe (The bit between the heating tank and the hose)


Examine the connections closely if you see any discoloration / signs of overheating then the TCO needs replaced.

Answered 8 years ago by Anonymous

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