Thermal relief valve with 3/8M BSP thread (16.5mm OD).
Must be fitted on the low pressure side of the pump system.
Seal all threads with thread tape when fitting.
Found on pressure washers on the low pressure 3/8F bypass port of the unloader
This valve opens to discharge water in the pump head when the temperature of the water in the pump get too hot (if the pump is left in bypass). This to protect the pump from overheating and damaging seals & valves.
