Viessmann B2HF, Installation And Service Instructions For Contractors

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25
On-site connections on HMU heat management unit
A B
C
D
Fig. 15
A
Diaphragm grommets, 230 V cables
B
Diaphragm grommets, extra low voltage (ELV)
C
Plug-in connection on underside of appliance
D
Plug for connecting sensors and PlusBus
Remove plug from the pack of installation compo-
nents.
■
Open diaphragm grommets as required. Thread
through only one cable at a time without a plug.
Ensure diaphragm grommets are airtight. If required,
remove plug from cable. After threading the cable
through, re-fit the plug to the wire ferrules.
■
Required plugs are supplied in separate packaging.
■
For cables without strain relief bushings, provide
strain relief in the wiring chamber in the form of cable
ties.
Outside temperature sensor
!
Fitting location for outside temperature sensor
■ North or north-westerly wall, 2 to 2.5 m above
ground level; in multi storey buildings, in the upper
half of the second floor
■ Not above windows, doors or vents
■ Not immediately below balconies or gutters
■ Never render over
Outside temperature sensor connection
2-core lead, length up to 35 m with a cross-section
of 1.5 mm
2
Installation sequence
Electrical connections
(cont.)
5593201
Installation