Potential failed hot water tank thermostat?

[suavegarve]

My hot water is way to hot, also radiators too hot to touch.

I checked the thermostat connected to the hot water tank, it shows 55 (advised setting) and the green light is illuminated for "water temp below". But the water is definitely well above 55.

Any advice on what the problem could be?

Many thanks.

 

[oldbuffer]

1. Radiators will generally be too hot to touch. On an older system they will have an average temperature of 72 degrees Celsius while on, on a more modern system, around 65.
2. How is the hot water thermostat connected to the hot water cylinder? You picture appears to show it attached to a wall. If that white wire from the bottom of it goes to a sensor this sensor should be in contact with the body of the cylinder, not on the outside insulation.
3. Picture of the hot water water cylinder with sensor / thermostat might help.

 

[suavegarve]

The thermostat does touch the copper on the tank. I removed it for the benefit of the pictures attached.

 

[CBW]

That doesn’t look like the same thermostat. Also check if the immersion is on.

 

[suavegarve]

Not sure what you mean by not the same thermostat. But one end of the wire is in a thermostat and the other end of the wire is in the reader that attaches to the copper on the side of the water tank.

The immersion is off.

 

[polesapart]

The old style Potterton cylstats are like this. (Haven't seen one for a while.)

Does the green light go out if you turn it down, with the sensor back on the cylinder?