At work we have a Worcester Heat Slave 20/25 oil fired combi boiler running the heating and hot water.

This is controlled by a Danfoss CP715 digital time controller.

No seperate room stat anywhere in the building. As far as i can tell the heating temp is controlled purely by the dials on front of boiler.

The landlord is having a fit about the amount of oil being used. He has asked me to do him a favour and look into how to fit a room stat to try and better control the temp of the building.

In our last house we had a vaillant boiler fitted and vaillant wireless stat / controller. Excellent bit of kit. Allowed me to not only select the on/off times but also what heating temp we wanted in each time zone.

Am i right in thinking i should be able to take off the Danfoss controller and replace it with a wireless reciever, then control the time and heat from a wireless unit from anywhere in the building (within range obviously).

Reason to ask is im wondering if anyone knows what wiring the reciever needs so i can investigate a bit more thoroughly before buying a controller.


I guess all the reciever does is switch the boiler on and off. Nothing more, nothing less - ie just acts as a switch.


Thanks in advance for help.

(New heating system is out of the question by the way, no gas here.)

Yep, you're right, they are normally just a simple switch. You should be able to find the installation manual for your boiler online somewhere which will have a wiring diagram.

Many boilers have an internal timer control panel and an additional connection for an external room stat / controller. These operate essentially as switches in series and the boiler runs when both "switches" are closed.

Here is the full documentation for your boiler.

[Edited on 7/11/08 by matt_claydon]

Thanks for that. Confirms what i thought.

Our other option is to keep the current timer and just fit a room stat. Only logic in changing to a wireless version is to save running the wiring for the new stat.

i just have to think about the 'fiddle' factor. ie non techy people in the office fiddling with the settings and buggering it up.

Landlords simple view was to have a basic room stat so last one to leave can turn it down, first one to arrive turns it up. i was just thinking one stage better to have the controller do it automatically.



A mate in the trade has also just said that if i go to city electrical, plumb centre, PTS etc they should be able to provide the wiring diagram applicable to swapping for what we have now to what they can recommend. Although from what i can see the reciever just needs a permanent 240V feed and connection back to the boiler.