Viessmann BW 301.A090, Installation And Service Instructions Manual

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66
Terminals Function Explanation
Note
■ No parameters need to be set.
■ The compressor is "forced" off as soon
as the contact opens.
■ The power-OFF contact signal causes
the supply voltage to the relevant com-
ponents to be switched off (subject to
power supply utility).
■ For the instantaneous heating water
heater, the stages to be switched off can
be selected (parameter "Output for in-
stant. heating water heater with power-
OFF").
■ The power supply for the heat pump con-
trol unit (3 x 1.5 mm
2
) and the cable for
the power-OFF signal can be combined
in a single 5-core cable.
■ For further information regarding power-
OFF, see chapter "Power supply".
LP1 X3.8
LP1 X3.9
P
Primary circuit pressure
switch and/or frost stat
or
Jumper
Requires floating contact:
■ Closed: Safety chain has continuity
■ Open: Safety chain interrupted; heat
pump shut down
■ Breaking capacity 230 V~, 0.15 A
On-site connection:
■ Connected in series if both safety com-
ponents are installed
■ Insert jumper if no safety compo-
nents are installed
X3.10
X3.11 Fault message, lag heat
pump in a cascade
or
Jumper
Requires floating contact:
■ Closed: No faults
■ Open: Fault
■ Breaking capacity 230 V~, 0.15 A
No jumper should be installed if a message
contact is connected.
Installation sequence
Overview of electrical connections
(cont.)
5848 164 GB