71
Maintenance Procedures
Check Flame Signal
The flame signal can be read from the Boiler
Information screen. It should be a min. 1
μ Α
−
DC
.
Check the ignitor for fouling or damaged
insulation if a low flame signal is read.
Check ground wiring and continuity as a cause
for low flame signal. Replace ignitor if condi-
tions are satisfactory.
Check Combustion Levels
Refer to page 57 of this manual for measuring
combustion levels and burner adjustments.
Check Flue Gas Temperature
1. Manually place the boiler into high fire.
See page 57 for procedure.
2. Navigate to the Boiler Information Menu
to observe the flue gas temperature. See
page 47 for procedure.
3. If the flue gas temperature is more than 54°F
[30°C] above the supply water temperature,
shut the boiler down and follow the heat
exchanger cleaning procedure below.
Clean Heat Exchanger
1. Shut down the boiler:
- Follow the instructions on Page 60 "To
Turn Off Gas to Appliance"
- Do not drain the boiler unless the boil-
er will be subject to freezing condi-
tions.
- Do not drain the boiler if freeze protec-
tion fluid is used in the system.
2. Allow the boiler to cool down to room tem-
perature before servicing.
3. Disconnect the gas piping and gas valve
wire harness connector.
4. Disconnect the wiring harness connectors
from the blower and remove the blower
retaining screws or nuts. Remove the blow-
er from the unit.
5. Remove the mounting nuts securing the
burner mounting plate to the heat exchang-
er and set aside.
6. Carefully remove the burner mounting
plate assembly from the heat exchanger.
Ensure combustion chamber insulation is
not damaged during removal of burner
mounting plate assembly. See WARNING
on page 72.
7. Carefully remove the combustion chamber
insulation from the heat exchanger and set
aside. See WARNING on page 72.
8. Use compressed air or water to remove any
accumulation from the heat exchanger flue
ways.
9. Re-install the combustion chamber insula-
tion onto the heat exchanger.
10. Re-assemble the burner mounting plate
assembly onto the heat exchanger. Ensure
the burner plate gasket and combustion
chamber insulation is in place and not dam-
aged, replace gasket and insulation if nec-
essary. See WARNING on page 72.
11. Re-assemble the blower onto the burner
mounting plate and reconnect the wiring
harness connectors.
12. Reconnect the gas piping and wire harness
to gas valve. Check for leaks, repair if nec-
essary.
13. Close isolation valves on the boiler water
piping to isolate the boiler from the heating
system.
14. Attach a hose to the boiler drain valve and
flush the boiler thoroughly with fresh
water by using the purge valves to allow
water to enter through the make-up water
line to the boiler.
