Immersion heater thermal cut out

[RaceDiagnostics]

Does anyone know where you can buy these? I'm guessing this one should be about 80 degC max. It trips all the time below 60 degC so needs changing.

 

[brightspark]

+you dont need the seperate cutout the modern thermostats have over temperature ones built in . its a little white pin sticking out, check the length before buying . dual safety thermostat

 

[sparkysy]

Most of the newer immersion heater stats have thermal protection built in.
Sy

Edit' @brightspark well beat me to it!!

 

[JOEPRO]

Does anyone know where you can buy these? I'm guessing this one should be about 80 degC max. It trips all the time below 60 degC so needs changing.

View attachment 431710

Erm

Your stat is set below 60c.

If that's the way it was then turn it up and try again?

 

[AKN]

The thermostat appears to be. Set around 48 deg C!

 

[RaceDiagnostics]

Erm

Your stat is set below 60c.

If that's the way it was then turn it up and try again?

The thermostat appears to be. Set around 48 deg C!

The thermal cut out triggers before the thermostat regardless.

 

[brightspark]

Erm

Your stat is set below 60c.

If that's the way it was then turn it up and try again?

yes but there normally set at 60 so if the over temperature is tripping its obviously faulty

 

[JOEPRO]

This is unclear.

Stat is clearly set at below 60c.

Complaint is that the circuit trips out at 60c and does not reach 80.

The way it's set there it should cut out at 60c.

Unless the OP can clarify as follows.

Are you saying that when you test just that black component with a continuity tester when over 60c it cuts out? And the thermostat is therefore still calling for heat?

 

[RaceDiagnostics]

The item that is circled is a resettable thermal cut out (the brown bit is a button), it trips every time the immersion heater is used before the main thermostat regulates the water temp.

 

[JOEPRO]

The item that is circled is a resettable thermal cut out (the brown bit is a button), it trips every time the immersion heater is used before the main thermostat regulates the water temp.

Its likely tripping out for good reason.

Time for a new immersion heater.That's 100% what I would be doing anyway and isolating it until replaced.

 

[brightspark]

The item that is circled is a resettable thermal cut out (the brown bit is a button), it trips every time the immersion heater is used before the main thermostat regulates the water temp.

so there for the main thermostat may be going over its set temperature or the safety cutout is going off early . changing to a dual thermostat cures the problem in one

 

[JOEPRO]

so there for the main thermostat may be going over its set temperature or the safety cutout is going off early . changing to a dual thermostat cures the problem in one

Do you mean to cut the wires and bypass the black safety device in this heater? And the function is picked up in a newer thermostat?

Quality immersion heaters are inexpensive. For me I consider it a safety item and I would still replace the whole heater with a factory assembled and tested unit VS cutting factory crimped circuiits in an existing heater exhibiting faults if that is what you meant I could be misunderstanding.

 

[RaceDiagnostics]

This is very simple, the thermal cut out trips at about 40 Deg c and is faulty, nothing else is faulty, the thermostat works fine. Brightspark answered the question in the second post, so problem sorted.

Replace thermal cut out and thermostat with new thermostat with integrated cut out. Job done with no need to drain the system.

Let's leave it there.

 

[pedrobedro]

Our immersion went pop a couple of weeks before Christmas and a new one was £30. The old one was in when we moved here 40 years ago so it's not done bad.

 

[JOEPRO]

This is very simple, the thermal cut out trips at about 40 Deg c and is faulty, nothing else is faulty, the thermostat works fine. Brightspark answered the question in the second post, so problem sorted.

Replace thermal cut out and thermostat with new thermostat with integrated cut out. Job done with no need to drain the system.

Let's leave it there.

My posts were meant to help.

I will leave it here with some further helpful suggestions. If a new stat is the route you choose and it trips again then consider other reasons why this could be happening.

Such as but not limited to:

Air in tank and part of element exposed.
Scaled up element.
Loose wiring connections.
Other heating input sources (where applicable) could also be tripping the heater.

 

[RaceDiagnostics]

Got round to this job this morning. £10 for a new thermostat with integrated cut out. Old thermostat and thermo switch out.

New thermostat in.

Job done, working perfectly.

Absolutely no reason to replace the entire unit.