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19
AST 14 C 258/00
Three-way valve section:
The boiler is provided with an automatic by-pass with non-return valve whose opening
threshold is of 400 mbar . In case of load losses in the system due to thermostatic valve
triggering, the by-pass ensures a minimum flow inside the primary exchanger.
It protects the primary condensing exchanger from overtemperatures due to the lack or a
poor water flow.
COLD WATER
D.H.W.
By-pass pipe with
non
-return valve
3-WAY
VALVE
FLOW
RETURN
Low water
pressure switch
Safety valve
3 bar
Expansion vessel
connection
SHUTTER
CARTRIDGE
IN
THERMOPOLYMERS
3-WAY STATUS
Domestic hot water
Shutter upwards
Actuator piston in rest
position
Central heating
Shutter downwards
Actuator piston in working
position
ACTUATOR
