Page 28
7 -
NOX units only
- Remove screw securing NOX
insert. Remove NOX insert. See figure 26.
8 -
Remove screws from both sides, top and bottom of
vestibule panel.
9 - Remove heat exchanger. It may be necessary
to spread cabinet side to allow more room. If so,
remove five screws from the left side or right side of
cabinet. See figure 27.
10 -
Backwash using steam. Begin from the burner
opening on each clam. Steam must not exceed
275°F.
11 -
To clean burners, run a vacuum cleaner with a soft
brush attachment over the face of burners. Visually
inspect inside the burners and crossovers for any
blockage caused by foreign matter. Remove any
blockage. Figure 25 shows burner detail.
12 - To clean the combustion air inducer visually inspect
and using a wire brush clean where necessary. Use
compressed air to clean off debris and any rust.
13 - Reinstall heat exchanger in vestibule. (Replace the
five screws in the cabinet from step 10 if removed).
14 - NOx units only - Replace NOx inserts.
15 - Reinstall collector box and combustion air
assembly. Reinstall all screws to the collector box
and combustion air inducer. Failure to replace all
screws may cause leaks. Inspect gaskets for any
damage and replace if necessary.
16 - Reinstall burner box and manifold assembly.
17 - Reconnect all wires.
18 -
Reconnect top cap and vent pipe to combustion air
inducer outlet.
19 - Reconnect gas supply piping.
20 - Turn on power and gas supply to unit.
21 - Set thermostat and check for proper operation.
22 - Check all piping connections, factory and field, for
gas leaks. Use a leak detecting solution or other
preferred means.
23 - If a leak is detected, shut gas and electricity off and
repair leak.
CAUTION
Some soaps used for leak detection are corrosive
to certain metals. Carefully rinse piping thoroughly
after leak test has been completed. Do not use
matches, candles, flame or other sources of ignition
to check for gas leaks.
24 - Repeat steps 24 and 26 until no leaks are detected.
25 - Replace access panel.
NOx INSERTS
NOx Insert
FIGURE 26
Remove 5 screws if necessary
(either side of cabinet)
1
2
3
4
5
FIGURE 27
