cylinder thermostat?

[wightcorp]

Hi all... thank you for your time.

I have a hot water cylinder with a cylinder thermostat mounted about half way up. It is set for 65 degrees C. When it reaches temperature it turns the boiler off (potterton suprima 60L) but it then comes straight back on again and repeats. I can here hot water been introduced to the cylinder coils to warm it up.

The temprature on the boiler itself is set to MAX (is this correct?)

I have changed the cylinder thermostat but the problem is still occurring.

I have test the thermostat in terms of when i manually turn it to zero it turns the boiler off (doesn't ask for heat) and the boiler remains off. When i turn it to 60 degrees the boiler turns on (asks for heat)

I am unsure if this is normal or not?

Once the cylinder reaches temperature, how long should it take to reduce enough for the boiler to have to kick in?

thank you

 

[leesparkykent]

The differential will normally be around 10~c. The ideal position is about 1/3 from the bottom of the cylinder. How well insulated is the cylinder?

 

[wightcorp]

The differential will normally be around 10~c. The ideal position is about 1/3 from the bottom of the cylinder. How well insulated is the cylinder?

thank you for your quick reply, i think it is well insulated. What do you mean by the differential will normally be around 10~c. is this between the temp of the boiler and the cylinder stat or the amount of degrees before the boiler should kick in?

i seems to be constantly asking for heat even thought the cylinder feels very hot

thank you

 

[jtsplumbing]

When you replaced the cylinder stat how meny wires did it have ?? should be 3 possible they are on wrong connections.

 

[wightcorp]

When you replaced the cylinder stat how meny wires did it have ?? should be 3 possible they are on wrong connections.

Yes three wires and and earth black brown blue i have tried swich both normaly closed and normaly opens over but no joy

 

[jtsplumbing]

You may be getting a feed from J/Box or motorised valve

 

[wightcorp]

You may be getting a feed from J/Box or motorised valve

Hi yes its fed by a junction box and there is a motorised valve next to the cylinder nt sure how it works though my plumbing skills are very limited

 

[Frog67]

Turn the boiler stat down. set it for about half way and see if that helps