Cylinder stat that works the opposite way to the standard ones

[manikki]

Does anyone know if I can buy such a thing as a Cylinder stat that works the opposite way to the standard ones?
I have a very basic heating system off a solid fuel back boiler plus an electric immersion in tank for back up. When the pump is off the water only heats up. When we turn on the pump the radiators also get warm. For years we have operated this manually, turning it on when needed and off before bed. It occurred to me that if we could have a thermostatic switch that sensed when the tank was up to temperature and turned the pump on then turned it off when the temperature dropped below a certain temperature, we could go to bed knowing the pump would go off in the night.
Does such a thing exist? Or can anyone suggest any other way to do it?

 

[Best]

Yes, - it is just a standard pipe stat. Usually has to be fitted on the return pipe where it leaves the copper cylinder coil. It will need accurately set to a temperature that will switch the pump on not too late.
It is the standard way to do solid fuel now.
You don't really need it fitted to the actual cylinder, because it is the solid fuel fire you are controlling and you just need to regulate the return from cylinder to fire. The immersion will then remain unaffected.
And welcome to the forum! :smile:

 

[manikki]

Yes, - it is just a standard pipe stat. Usually has to be fitted on the return pipe where it leaves the copper cylinder coil. It will need accurately set to a temperature that will switch the pump on not too late.
It is the standard way to do solid fuel now.
You don't really need it fitted to the actual cylinder, because it is the solid fuel fire you are controlling and you just need to regulate the return from cylinder to fire. The immersion will then remain unaffected.
And welcome to the forum! :smile:

Thank you for your speedy response. I can see that it would work with the return pipe so I have taken your advice and looked for pipe thermostats online. However I an still coming up with ones that work the same way as the cylinder stats. I.e. Contact is made when the temp drops bellow the level it is set at. I need one that breaks contact bellow a set temperature and makes contact to switch on the pump when the set temp is reached. I don't know how to search for what I need. Is it possible to suggest a model number or send a link to the correct item.

 

[tamz]

Danfoss APT.
Permanent live to C pump live to 2

 

[tamz]

And since i have nothing better to do here is a wiring diagram


You need an un-switched and switched fused spur, both fused at 3 amp.
The reason for 2 spur switches is you will still want the heating on at times that suit you so instead of having to wait until the hw is up to temperature you can bypass the pipe stat and just turn the heating on.