All of my thermostats are blank – Heatmiser FAQ

This is when none of the thermostats are showing no display. Not even a power icon.

Does you thermostat look like this?

If yes, tap the power button to see if the unit switches back on.
If no or if it is this unit does not switch on?
Does it have a battery tray at the bottom?
If yes, push up, release the battery tray by pushing up and replace the AAA batteries.
Display should come on.

If hard wired thermostats

If they are controlling electric underfloor heating
Check the PCB board to see if the fuse spur is switched on
If still blank, call an electrician for investigation.
If they are controlling water underfloor heating
Look for a wiring centre and see if it has any lights on it. It may look like this.

At this stage, you may need an electrician to investigate
If the power light is on, it could suggest a wiring fault between the UH8 and the thermostats
If the power light is off, check the PCB board to see if the fuse spur is switched on.
If it is off, then it is possible that an internal fuse has blown inside the wiring centre, this can be caused by any of the following
- Faulty actuator
- Faulty pump
- Faulty valve
- Faulty thermostat
- There is a slim chance it could be the wiring centre
We would advise a local electrician or a heating engineer to test the wiring centre and the components before changing the fuse, otherwise damage could occur to the wiring centre.

An electrician can ring us on 01254 669090, option 2, lines are open from 9am to 4:30pm Monday to Friday.

The following information is for the electrician only