Replacing a Randall 4033 with a homexpert THR872CUK

[suse71]

Hi
Can anyone help? I have a Randall 4033 timer which is now broken (clock not moving). Can I replace it with a homexpert THR872CUK? My thermostat isnt great either hence the need for a new thermostat too.

I have the randall wiring diagram and the meanings from this site:-
1 DHW COM (ignore)
2 heating on
3 heating off
4 water on
5 water off
6 L
7 N
Earth
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The homepert diagram just shows A B and C. Can anyone tell me what goes where or is there no direct replacement?

Thanks

Untitled

• suse71
• 3 Nov 2013
• 1

 

[Whitespirit66]

The Randall is a programmer to control hw and ch. The Homexpert is just a wireless stat that controls only ch. You need to give more details about your current setup, eg. boiler, motorised valves, if you have a hw cylinder, etc.

If you need a 2 channel programmer to control hw and ch timings, plus a room stat, I would consider the Drayton Mitime T720R. It is a programmer as well as having a wireless RF room stat.

 

[suse71]

Thanks - thought as much. I have a boiler and hot water cylinder tank. No thermostatic valves, motorised valves on the boiler set up.