Wireless starter kit

msmith1504

Have replaced Drayton wireless thermostat and SCR receiver plus Honeywell 699. Hot water works ok but CH doesn’t work. It seems the thermostat/control unit just won’t trigger the boiler. Any thoughts?
Thank you in advance.

johnnyp78

Check your wiring, check for any existing items wired in to the boiler such as a timer or outdoor temperature sensor.

msmith1504

Thanks johnnyp78. I’ve checked and double checked the wiring and it’s exactly as Tado advised during installation. I’ve removed original wireless thermostat and receiver and all connected wiring.
Light on the new Tado receiver suggests wired ok for CH but it’s just not kicking up the boiler. A bit annoying.

johnnyp78

If you use the desktop version of the forum you can post photos of the wiring, someone may have an idea.

msmith1504

Here is the current Tado receiver wiring and the original Honeywell control unit it's replacing.

wateroakley

1. How have you bridged the Drayton wireless SCR receiver? Unless the SCR is bridged, the CH wont call the CH valve and boiler for heat.
2. When you call for heat on the CH ... a) Does the CH light come on the wireless receiver? b) Can you hear the relay 'click'? c) Is there power on the CH NO terminal ? You can use the 'test' button on top of the wireless receiver to check this.
3. P.s, don't forget to terminate the Earth wire (assuming that is actually E).