Operating instructions

Part number 550-141-887/0800
17
AHE Series 4 Direct Vent Wall-Mounted Boilers — Boiler Manual
4d Water piping — pressure test
Perform hydrostatic pressure
test
Pressure test boiler before attaching gas piping or
electrical supply.
1. Close shutoff valves between boiler and system.
Remove air vent cap on top of boiler and open air
vent on circulator/mixing valve 2 full turns.
2. Feed water into the boiler through cold water fill
— Do not exceed 45 psig. Boiler is filled and air
is vented when boiler air vent valve is depressed
and water spurts from valve. Screw cap back on air
vent on boiler and close air vent on circulator/
mixing valve completely, then open both one full
turn. Turn off cold water fill.
3. Test at 45 psig for more than 10 minutes.
Do not leave boiler unattended.
Cold water fill could expand and
cause excess pressure, resulting in
severe personal injury, death or
substantial property damage.
4. Make sure constant gauge pressure has been
maintained throughout test. Check for leaks. Repair
if found.
Leaks must be repaired at once.
Failure to do so can damage boiler,
resulting in substantial property
damage.
Do not use petroleum-based
cleaning or sealing compounds in
boiler system. Severe damage to
boiler will occur, resulting in
substantial property damage.
5. With shutoff valves still closed, attach hose adapter
and hose to one drain valve and discharge water
through other drain valve until no air is present.
Use line water pressure.
6. Close both drain valves. Remove hose and adapter.
7. Open cold water fill. Fill pressure should be
between 30-40 psig
.
8. Open shutoff valves.
4c Water piping — refrigeration systems
Prevent chilled water from
entering boiler
Install boiler so that chilled medium is piped in parallel
with the heating boiler. Use appropriate valves to prevent
chilled medium from entering boiler. See Figure 14 for
typical installation of balancing valve and check valve.
If boiler is connected to heating coils located in air
handling units where they can be exposed to refrigerated
air, use flow control valves or other automatic means to
prevent gravity circulation during cooling cycle.
Figure 14 Piping refrigeration systems