Immergas Intermittent Power or Internal Fault

Thermostat frequently resets or reboots on its own

This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.

If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.

Possible Causes

Loose power connections, Voltage dips from boiler control board, Internal power regulator fault, Firmware instability

Safety: Turn off boiler power before checking wiring.

Step 1 – Tighten terminals: Check and tighten all thermostat power and BUS terminals at both thermostat and boiler.
Step 2 – Check supply stability: A technician can monitor the low-voltage supply for drops when the boiler starts.
Step 3 – Firmware update: Update thermostat firmware to the latest version.
Step 4 – Replace thermostat: If resets continue with stable power, the internal electronics are likely faulty and the thermostat should be replaced.

Medium 3/5

Immergas thermostat main PCB

Check Price on Amazon

We may earn a commission from links on this page.