Worcester Bosch Frost Thermostat 87161423930

The Worcester Bosch frost thermostat, part number 87161423930, is a temperature-sensing control used across Worcester Bosch oil and gas appliance ranges. It monitors the temperature around the appliance or in the space where the pipework runs and signals the boiler to fire as conditions approach freezing. This keeps the appliance and its water circuit protected during cold spells and supports safe, dependable operation.

• The boiler fails to fire in cold weather, leaving the appliance and pipework exposed to freezing
• The boiler runs when the ambient temperature is well above the frost setting
• Heating or hot water behaves erratically during cold spells
• Frost protection no longer responds where the appliance sits in an unheated space such as a garage or outbuilding
• Visible damage, corrosion or loose connections at the thermostat or its wiring

• Check the appliance model and serial number against the compatibility list to confirm this thermostat suits your unit.
• Note the alternative part number 1018149 when cross-referencing older service documentation.
• Confirm the thermostat's mounting position and wiring before removal, as frost stats are often sited away from the boiler itself.