scope:

This European Standard specifies the safety, construction and performance requirements for mechanical thermostats intended for use with gas appliances and similar use, hereafter referred to as "thermostats".
This European Standard covers type testing only.
It applies to thermostats controlling the gas flow directly or indirectly through an integral gas valve, and which do not require external electrical energy for their operation.
It applies to thermostats of nominal connection sizes up to and including DN 50 with declared maximum inlet pressures up to and including 500 mbar (50 kPa) for use with one or more fuel gases in accordance with EN 437.
It only applies to thermostats used with gas appliances which are not installed in the open air.
Thermostats dealt with in this standard are intended for control functions.