RT310RF : Questions & Answers (6.1.1) .
My receiver has a flashing red light, what does this mean ?
A flashing red light on the receiver means the Receiver and Thermostat have lost their communications link and the devices need pairing.
I have a blank screen / no display and new batteries do not bring the screen back on ?
If the batteries are not changed with the correct procedure (ie. allowing time for the internal capacitors to fully discharge before the new batteries are fitted) or before the batteries become totally drained, the thermostat can go into a locked / suspended state and appear to not work. Your thermostat is not broken, but you need to click on the link below and follow the procedure :
Why does my screen show 5’C and not let me increase the temperature ?
This is because your Thermostat is in Frost Protection Mode. Simply Press the Frost Button to exit Frost Protection Mode and then you will be able to change the temperature.