FCU 500, FCU 505 · Edition 02.17
33
Valve proving system
7 Valve proving system
The FCU..C1 is fitted with an integrated valve proving
system. This allows the tightness of two or more gas
solenoid valves and the pipework to be checked, see
page 34 (Tightness control). Alternatively, the closed
position of a gas solenoid valve can be checked using a
POC switch, see page 57 (Proof of closure function).
Once the test has been carried out successfully, the
furnace is enabled for start-up.
The tightness control function satisfies the require-
ments of EN 1643 (Valve proving systems for automat-
ic shut-off valves for gas burners and gas appliances).
By checking the closed position using the proof of clo-
sure function, the FCU complies with the requirements
of NFPA 85 (Boiler and Combustion Systems Hazards
Code) and NFPA 86 (Standard for Ovens and Furnaces).