Viessmann VITOCAL 242-S Installation And Service Instructions Manual page 47

Electrical connection
Terminals Function
X3.1 Switched phase
X3.3 Flow switch
X3.4
X3.6 Power-OFF (factory-fitted
X3.7 jumper)
G
(cont.)
Explanation
Via control unit ON/OFF switch
Note
Observe the total load 1000 W of all con-
nected components.
Requires zero volt N/O contact:
■ Closed: Heat pump in operation
■ Open: Heat pump shut down
■ Breaking capacity 230 V~, 0.15 A
Remove jumper when connecting.
Requires zero volt N/C contact:
■ Closed: Heat pump in operation
■ Open: Heat pump shut down
■ Breaking capacity 230 V~, 0.15 A
Remove jumper when connecting.
Note
■ No parameters need to be set
■ The compressor is "forced" off as soon as
the contact opens.
■ Subject to the power supply utility the
power-OFF signal switches off the supply
voltage of the respective working part.
■ For the instantaneous heating water
heater, the stages to be switched off can
be selected (parameter "Output for in-
stant. heating water heater at power-
OFF 790A").
■ The power supply for the heat pump con-
trol unit (3 x 1.5 mm
the power-OFF signal can be combined
in a single 5-core cable.
■ For further information regarding power-
OFF, see chapter "Power supply".
Installation sequence
2
) and the cable for
47