Safety Connections; Installing Safety Devices On The Boiler; Low Water Cut-Off - Viessmann Vitodens 100-W B1HA 26 Installation And Service Instructions Manual

Connections

Safety Connections

Legend
A Pressure relief valve
B Brass adaptor NPT
C O-ring
D Retaining clip
Minimum connection diameters:
Pressure relief valve .............................................. ¾ in.
Discharge pipe ..................................................... ¾ in.
IMPORTANT
Install the (approved) factory supplied pressure relief valve.
Removal of air from the system must occur via use of air
vent(s) in the system supply. To ensure the boiler can be
purged of all air, ensure supply/return water lines do not
contain restrictive piping where air could be trapped.
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Vitodens 100-W, B1HA/B1KA 26 to 125 Combi Installation/Service

Installing safety devices on the boiler

1. Assemble the brass adaptor B, O-ring C, and
retaining clip D to the boiler.
2. Apply sufficient amount of pipe sealant to adaptor B.
3. Install pressure relief valve A and tighten.
4. Install discharge pipe on pressure relief valve in such
a way that...
- the end of the pipe is not threaded.
- the pressure relief discharge pipe extends to a
floor drain and ends approximately 6 in. (150 mm)
above the drain.
Ensure that...
- there is no shutoff valve installed in the discharge pipe.
- discharge pipe diameter is not reduced.
- discharge is not piped to outdoors.
WARNING
Do not install an isolation valve between boiler and
pressure relief valve.
The discharge pipe for the pressure relief valve must
be oriented to prevent scalding of attendants.
Pipe pressure relief valve discharge pipe close to floor
drain. Never pipe discharge pipe to the outdoors.

Low water cut-off

A low water cut-off may be required by local codes. Do
not install an isolation valve between boiler and low water
cutoff (see subsection entitled "Boiler with low water
cutoff" on page 34 in these instructions).
Pressure relief valve discharge pipe
The pressure relief valve discharge pipe C must be
supported using either a ceiling mounted support A or
a wall mounted support B.
Legend
A Ceiling mounted support (field supplied)
B Wall mounted support (field supplied)
C Pressure relief valve discharge pipe (field supplied)