Viessmann WB1A007 - Page 22

Boiler Connections
22
Connections (continued)
Heating water connections
Legend
BWR Boiler water return, ¾”
BWS Boiler water supply, ¾”
BD Boiler drain
BF Boiler fill
GC Gas connection, ¾” NPTM
PRV Pressure relief valve
NPT National Pipe Thread
PG Pressure gage
1. Thoroughly flush heating system
(particularly before connecting the
boiler to an existing system).
2. Connect boiler to the heating
system.
Max. operating pressure 3 bar/ . . . . .
45 psig . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Test pressure 4 bar/ . . . . . . . . . . . . . . . . . . . . . . . . . . .
60 psig . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Damage resulting from pressure
exceeding those values stated is not
covered by Viessmann warranty.
H Use a two-hand wrench method
when tightening fittings or piping
onto the boiler connectors. Use one
wrench to prevent the boiler pipes
from twisting and the second wrench
to tighten the fitting or piping.
Failure to support the boiler
connection could damage the boiler
and its internal piping.
H All plumbing must meet or exceed all
local state and national plumbing
codes.
SUPPORT ALL PIPING USING
HANGERS. DO NOT support piping by
the unit or its components.
H Use isolation valves to isolate system
components.
5581 775 1.35581 775 1.3
BWS
BWR
NPT
GC
PRV
BD
PG
BF
IMPORTANT
IMPORTANT