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20
AST 14 C 257/00
Three-way valve view:
The boiler is fitted with an automatic bypass and a non-return valve, with an opening
threshold of 400 mb ar. In the event of system load losses due to intervention of the
thermostatic valve, the bypass ensures a minimum flow inside the primary exchanger.
Its job is to prevent the primary condensing heat exchanger from overheating caused by
low or no water circulation.
COLD WATER
DHW
B ypass pipe with
non-return valve
3-WAY
VALVE
FLOW
RETURN
Pressure
transducer
3 bar
saf ety valve
Expansion vessel
connection
SHUTTER
THERMOPOLYMER
CARTRIDGE
3-W AY VALVE STATUS
DHW
Shutter pointing up
Actuator piston home
Heating
Shutter pointing down
Actuator piston thrust
ACTUATOR
