Instructions / Assembly

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7.1.4. Flame Roll-Out Safety Switch
Heaters are equipped with a thermal cuto device to
prevent ame roll-out in the event the heat exchanger
becomes blocked. This is a “single-use” type fusible link
or thermal fuse, that must be replaced when disabled
by an over-temperature condition, caused by excessive
restriction in the heat exchanger ue passage, roll-out,
high winds, etc.
7.1.5. High Limits
The heater is equipped with two automatic high limits.
Both are located in the In/Out header. Both are set to open
at 135°F (57°C).
NOTE: An erratic high limit is often characteristic of an
internal heat exchanger problem, e.g. scale build-up,
defective bypass. Refer to Troubleshooting section.
7.1.6. High Limit Removal
1. Shut off main electrical power switch to heater.
2. Remove rear In/Out inspection panel.
3. Remove defective high limit and replace with a new
high limit.
4. Replace inspection panel.
Figure 39. High Limit Switch
7.1.7. Burner Tray Removal
1. Shut off main electrical power switch to heater.
2. Shut off gas upstream of heater.
3. Remove front door
4. Disconnect gas line from gas valve.
5. Remove (3) screws holding the anti-rotation bracket
in place.
6. Remove bracket an set aside.
7. Remove (4) screws as shown in the image.
8. Disconnect wiring from gas valve.
9. Remove (2) screws holding the control panel up.
10. Flip the control panel forward.
11. Disconnect ignition wire and remove with burner
tray.
12. Reverse above procedure to reinstall.
Figure 40. Burner Tray Assembly
7.1.8. Gas Valve Removal
1. Remove burner tray.
2. Disconnect pilot tubing from gas valve
3. Rotate the gas valve counter clockwise to remove
valve from nipple.
4. Reverse above procedure to reinstall.
SCREWS HOLDING
TRAY IN PLACE
Figure 41. Gas Valve Removal
7.1.9. Pilot Removal and Cleaning
1. Remove burner tray from heater
2. Disconnect tubing from gas valve.
3. Remove (2) screws holding pilot bracket in place.
4. Remove the pilot assembly by pushing the pilot
5. Remove the locating pilot screw from the bracket to
release the pilot assembly.
6. Reverse above procedure to reinstall