Safety unit of water heater - has sub assembly enabling safety valve to be replaced independently of unit

摘要

The safety unit of a water heater contains a stop valve, a non-return valve, a safety valve and an overflow connection. The safety valve is made as a sub assembly with a body which has a male, thread on its largest dia, and a locating flange. It is screwed into the main part of the unit so that the sub-assembly can be removed and replaced independently of the whole unit. The main part has a cylindrical body into which the sub-assembly screws and which also has connections for cold water inlet flow to the heater and an overflow discharge. The sub assembly has a spring loaded valve closing on a seat within the sub assembly body.