Installation & Operation Manual
65
12
Maintenance
(continued)
Perform start-up and checks
1.
Start boiler and perform checks and tests specified in
Section 10 - Start-up.
2.
Verify cold fill pressure is correct and that operating
pressure does not go too high.
Check burner flame
1.
Inspect flame through observation window.
2.
If the flame is unsatisfactory at either high fire or low fire,
turn off boiler and allow boiler to cool down. Remove the
burner and clean it thoroughly using a vacuum cleaner or
compressed air. Do not use compressed air to clean
burner if performed inside a building.
3.
Remove the burner, reference FIG. 12-2 below.
4.
When replacing the burner, ensure gasket is in good
condition and positioned correctly (FIG. 12-2).
Figure 12-2
Burner Assembly
Check flame signal
1. At high fire the flame signal shown on the display should
be at least 10 microamps.
2. A lower flame signal may indicate a fouled or damaged
flame sense electrode. If cleaning the flame sense
electrode does not improve, ground wiring is in good
condition, and ground continuity is satisfactory, replace
the flame sense electrode.
3. See Section 3 - Troubleshooting of the Knight Wall
Mount Service Manual for other procedures to deal with
low flame signal.
Review with owner
1. Review the Knight Wall Mount User’s Information
Manual with the owner.
2. Emphasize the need to perform the maintenance
schedule specified in the Knight Wall Mount User’s
Information Manual (and in this manual as well).
Cleaning boiler heat exchanger
1.
Shut down boiler:
• Follow the “To Turn Off Gas to Appliance” instructions
for the boiler in Section 10 - Startup.
• Do not drain the boiler unless it will be exposed to
freezing temperatures. If using freeze prevention fluid
in system, do not drain.
2.
Allow time for the boiler to cool to room temperature if it
has been firing.
3.
Remove the blower assembly (gas air/arm) from the heat
exchanger access cover. Set bolts aside.
4.
Remove the nuts securing the heat exchanger access cover to
the heat exchanger and set aside.
5.
Remove the heat exchanger access cover, cover gasket(s) and
chamber insulation assembly.
The boiler contains ceramic fiber materials.
Use care when handling these materials per
instructions on page 3 of this manual.
Failure to comply could result in severe
personal injury.
6. Use a vacuum cleaner to remove any accumulation on the
boiler heating surfaces. Do not use any solvent.
7. Finish cleaning using a clean cloth dampened with warm
water.
8. Install access cover gasket, chamber insulation assembly and
cover.
9. Secure nuts on the studs. DO NOT overtighten.
10. Re-install the blower assembly (gas air/arm) using the bolts
set aside in Step 3.
11. Close isolation valves on piping to isolate boiler from
system. Attach a hose to the boiler drain and flush boiler
thoroughly with clean water by using purging valves to allow
water to flow through the water make-up line to the boiler.
12. When the boiler has been flushed, restore boiler to
operation.
13. Perform start-up and check-out procedures in Section 10 -
Startup.
Oiled bearing circulators
1. The circulator shipped with the Knight wall mount boiler is
water-lubricated. No oiling is required.
2. Check other circulators in the system. Oil any circulators
requiring oil, following circulator manufacturer’s
instructions. Over-oiling will damage the circulator.
3. Replace the boiler front access cover.
WARNING
3. Remind the owner of the need to call a licensed contractor
should the boiler or system exhibit any unusual behavior.
4. Remind the owner to follow the proper shutdown
procedure and to schedule an annual start-up at the
beginning of the next heating season.
