Replacing old programmer with progammable room stat

[rob7475]

Hi,

I've got an old ideal conventional boiler that is controlled by a glow worm mastermind programmer. At the moment there is no room stat in the house so I want to replace the programmer with a wireless room stat.

Is it fairly straight forward to change the programmer? Currently the wiring from the boiler, pump and programmer all go to a junction box near everything. If I post some pictures of the current setup - would anyone be kind enough to point me in the right direction?

Thanks,

Rob

 

[JohnD]

you need a room stat as well as a programmer, not instead. Else hot water will be on 24 hrs

 

[Whitespirit66]

Wire the new stat receiver into existing wiring centre connections. Keep the programmer, and turn the heating on to constant on it.

Therefore, the new wireless stat will control the heating times, and the old programmer will control the water.

You need pictures of the programmer connections, as well as inside the wiring centre box. Don't forget to say what make the programmer is, the boiler, and what system, eg. 3 port valve.

 

[rob7475]

Thanks for the replies.

I can't just have the heating on constant on the old programmer - the hot water has to be switched on before the heating is allowed to be switched on. If i just keep the existing programmer as it is, can I add just a wireless room stat so i can control the temp of the heating?

 

[JohnD]

- the hot water has to be switched on before the heating is allowed to be switched on.

That indicates that your programmer is set to Gravity HW feed (the boiler supply to the cylinder is not pumped).

To check if this is correct, let the cylinder cool down by turning off the boiler while you have your next bath, so it will be calling for heat (or turn the cylinder stat to max if you know how)

then turn off the CH at the programmer and turn on the HW. Does the pump start? If yes, you have a pumped HW circuit, and the programmer problem can be addressed quite easily. If no, or if you have no cylinder stat, then different work is needed. (A gravity HW circuit is slower and less efficient than a pumped one)

Your new room stat can be used to control the temperature of the heating anyway (it does not need to be a wireless one) and if you get one with a timer, it will control the times but they can never be greater than the "on" times at your programmer. If you felt like it, you could fit a simple room stat with a wired connection and start controlling your heating more efficiently, at quite low cost.

 

[Whitespirit66]

Thanks for the replies.

I can't just have the heating on constant on the old programmer - the hot water has to be switched on before the heating is allowed to be switched on. If i just keep the existing programmer as it is, can I add just a wireless room stat so i can control the temp of the heating?

Yes you can. This Danfoss one is suitable for your system, and doesn't have a programmer built in. It's what I install for situations like yours.

http://www.plumbnation.co.uk/site/d...ith-rx-1-radio-frequency-receiver-087n727600/

 

[rob7475]

Hi Whitespirit,

The danfoss stat looks like just what I need.

Does this just wire in to the terminal box on the wall near the boiler and if so, how do i find which terminals to wire it in to?

Thanks again,

Rob

 

[Whitespirit66]

Hi Rob

If yours is the system with a mid position motorised valve (5 wires to it), its any easy install.

L and N on the stat receiver go to L and N on the wiring centre connector strip (usually the left 2 terminals). This supplies the juice to run the receiver.

Next, disconnect the heating ON wire from programmer where it connects to the connector strip and connect it to terminal 2 on the stat receiver instead.

Lastly, disconnect the white wire for the motorised valve where it connects to the connector strip, and connect it to terminal 3 on the stat receiver.


See 'Receiver Wiring (RF Only)' on this link for a diagram - second diagrams down. You need the diagram on the left for RX1.

http://www.heatingcontrolsonline.co.uk/instructions/RET-B.pdf

Ian