Drayton Iflo Digistat +2 RF thermostat shows error E16 when powered up after fitting new batteries. I believe this is a thermostat error, but is it repairable or do I need a new unit? Plus, when I check for connection (power up after pressing the No.1 and No.2 buttons in sequence ) the red light flashes , so I believe I have connection, but I can't clear the error, any ideas please?

Gareth, November 2022

Did a quick search and found these:

https://www.justanswer.co.uk/hvac/fdn5s-fault-code-e16-drayton-thermostat-fix.html

https://www.ultimatehandyman.co.uk/forum1/viewtopic.php?t=57448

5rf, November 2022