Startup - Dunkirk Q90-125 Installation, Operation & Maintenance Manual

Water Treatment And Freeze Protection - See
Appendix A
Filling Boiler With Water And Purging Air For Systems
With Diaphragm Type Expansion Tanks
Refer to the appropriate diagrams "Near Boiler Piping" on
page 8 and 9.
1. Close all zone service valves on supply and return
piping. Open feed valve and fi ll boiler with water. Verify
air vent is open. Hold relief valve open until water runs
air free for fi ve seconds to rapidly bleed air from boiler,
let relief valve snap shut.
2. Open zone service valve on supply pipe for fi rst zone.
Open purge valve on fi rst zone. Feed water fi lls zone,
pushing air out purge valve. Close purge valve when
water runs air free. Close zone service valve.
3. Repeat step 2 for all remaining zones.
4. Open all service valves. Any air remaining trapped
in return lines between service valves and boiler
are pushed towards air vent when boiler is placed in
operation.
5. 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.

10 - STARTUP

Filling Boiler With Water And Purging Air For Systems
With Conventional Closed Type Expansion Tanks
Refer to diagrams on "Near Boiler Piping" on page 8 and 9
for more information.
1. Close all zone service valves on supply and return
piping. Close expansion tank service valve. Drain
expansion tank. Open feed valve and fi ll boiler with
water. Hold relief valve open until water runs air free
for fi ve seconds to rapidly bleed air from boiler, let
relief valve snap shut.
Open zone service valve on supply pipe for fi rst zone.
2.
Open purge valve on fi rst zone. Feed water will fi ll
zone, pushing air out purge valve. Close purge valve
when water runs air free. Close zone service valve.
Repeat step 2 for remaining zones.
3.
4. 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
homeowner doesn't accidentally close it.
5. Open all service valves. Any air remaining trapped
in return lines between service valves and boiler will
push towards expansion tank when boiler is placed in
operation.
6. Inspect piping system. Repair any leaks immediately.
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