Dunkirk Q95M-200 Modulating Condensing Boiler - Manual (Page 23)

Water Treatment And Freeze Protection - See
Appendix B
12.1 Filling Boiler With Water And Purging Air
1. Systems With Diaphragm Type Expansion Tanks
A. Close all zone service valves on supply and return
piping. Open feed valve and fill boiler with water.
Verify air vent is open. Hold relief valve open until
water runs air free for five seconds to rapidly bleed
air from boiler, then let relief valve snap shut.
B. Open zone service valve on supply pipe for first
zone. Open purge valve on first zone. Feed water
will fill zone, pushing air out purge valve. Close
purge valve when water runs air free. Close zone
service valve.
C. Repeat step 2 for all remaining zones.
D. Open all service valves. Any air remaining trapped
in return lines between service valves and boiler
will be pushed towards air vent when boiler is
placed in operation.
E. Inspect piping system and repair any leaks
immediately.
12 - BOILER STARTUP
2. Systems With Conventional Closed Type Expansion
Tanks
A. Close all zone service valves on supply and return
piping and close expansion tank service valve.
Drain expansion tank. Open feed valve and fill
boiler with water. Hold relief valve open until water
runs air free for five seconds to rapidly bleed air
from boiler, then let relief valve snap shut.
B. Open zone service valve on supply pipe for first
zone. Open purge valve on first zone. Feed water
will fill zone, pushing air out purge valve. Close
purge valve when water runs air free. Close zone
service valve.
C. Repeat step 2 for all remaining zones.
D. Open expansion tank service valve and tank
vent. Fill tank to proper level and close tank vent.
Remove handle from expansion tank service valve
so it is not accidentally closed.
E. Open all service valves. Any air remaining trapped
in return lines between service valves and boiler
will be pushed towards expansion tank when boiler
is placed in operation.
F. Inspect piping system. Repair any leaks immediately.
NOTICE
Do not use stop leak compounds. Repair leaks in
threaded connections of aluminum boiler sections.
Aluminum threads do not seal themselves.
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