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Connections
22
Safety Connections and Pressure Testing
Installation Instructions
Viessmann Safety Header
(Accessory)
Install safety devices on the boiler
Install safety devices.
1.
Install pressure relief valve, discharge
pipe, air vent and pressure gage as
described in installation instructions
of Safety Header.
2.
Install discharge pipe on pressure
relief valve. The end of the pipe must
not
be threaded.
The pressure relief discharge pipe
should extend to a floor drain and
end approximately 6” / 150 mm
above the drain.
Do
not
install shut-off valve in
discharge pipe.
Do
not
reduce discharge pipe
diameter.
Do
not
pipe discharge to outdoors!
Minimum connection diameters:
Pressure relief valve
3
/
4
“
. . . . . . . . . . . . . . . . . . . . . . . . . .
Discharge pipe
3
/
4
“
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Piping to precharged
expansion tank
3
/
4
“
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
This boiler does
not
require a flow
switch.
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.
5167
404
v1
.9
IMPORTANT
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.
WARNING