cylinder thermostat and motorised valve.

[jobloggs]

Hi

My hot water cylinder is a long way from the boiler in an older house with a basic pumped CH system. Would it be possible to fit a motorised valve close to the cylinder and contolled by a cylinder thermostat in order to manage the temperature of the hot water more efficiently. There is an electricity circuit close by.

Would I need any other kit than the valve and thermostat? Do they operate at mains voltage? Does it matter if the valve is on the inlet or return side of the indirect coil?

Any advice gratefully recieved.

 

[ChrisR]

Make sure you leave path ot the vent, from the boiler, clear of any valves - which may mean putting your valve in the return side of the loop. May mean boiler on with your valve shut so you may need a bypass. Not if solid fuel either!
Yes it does work, you can get liquid operated valves designed for the purpose too.
And if the loop isn't pumped you can turn a new pump on too, in which case add a pipe stat so the pump only comes on if the water is hot.

You can also get radio cylinder thermostats which you can use to make the system conventional fully pumped without the wiring problem (Danfoss).

 

[chrishutt]

You need to "interlock" your cylinder controls with the boiler (so that boiler only fires when there is a call for heat), so unless you can run a length of cable between cylinder and boiler you really need the Radio Frequency kit from Danfoss mentioned above.

You can buy it from Screwfix for £85 (or there's a kit with a programmably RF room stat as well). Then you can locate the motorised valve near the boiler, or possibly use a 3 port mid-position valve rather than 2 x 2 ports