Our UH8-RF/RF Switch have a function called fail safe.
What is Fail safe?
Fail safe is designed to prevent frost damage e.g. pipes freezing by heating the zone affected for 12 minutes in every hour (20% of the time) until the signal is restored. This happens if the UH8-RF/RF Switch haven't received a signal from the thermostat within a 40 minute period.
What can cause fail safe to happen?
1. The neoAir / Slimline-RF has run out of battery
2. The signal is poor between the neoAir/Slimline RF and the RF Switch/UH8-RF
3. The aerial on the UH8-RF/UH8-RF V2 is not pointing upwards
Whilst you can turn this function off, we don't recommend this because you remove the safety system in your home. It also masks a potential signal issue that we would recommend is identified and corrected by the use of our wireless repeaters.
If you do want to disable fail safe, please consult the thermostat product manual for instructions on how to do this.