A.O. Smith Water Heater Replacing the Manifold/Burner, Assembly, Replace door gasket if damaged

10. Reposition the two piece wire connector in the	Replacing the Manifold/Burner	Assembly
manifold door opening and secure it with the retainer
clip.

11.Carefully bend the new pilot tube and thermocouple to match the bend of the manifold tube. NOTE: When

bending DO NOT crimp or crease the pilot tube or thermocouple. (Figure 25)

12.Place the new brass ferrule nut on the pilot tube before proceeding to the next step.

13.See Replacing the Manifold/Burner Assembly.

External Inspection & Cleaning of the Base-Ring Filter

,At least annually check the base-ring filter (Figure 26)

for any dust or debris that may have accumulated on the filter screen. NOTE: If the water heater is located

in an area that is subjected to lint and dirt, it may be necessary to check the base-ring filter more frequently.

,Follow the Lighting Instructions to turn off the water heater and allow it to cool for 10 minutes before attempting to clean the base-ring filter.

,Use a vacuum cleaner with a hose attachment to remove any dust or debris that may have accumulated on the filter. NOTE: If unable to inspect or clean the

base-ring filter, follow the "Cleaning the Combustion Chamber and Flame-arrestor" instructions.

,After the base-ring filter has been cleaned, follow the Lighting Instructions to return the water heater to service.

Cleaning the Combustion Chamber and Flame-arrestor

,Follow procedure outlined in "Removing the Manifold/ Burner Assembly".

2.Use a vacuum cleaner/shop vac to remove all loose debris in the combustion chamber (Figure 29). Use compressed air to clear any dust or debris that may have accumulated in the flame-arrestor.

COMBUSTION CHAMBER

FLAMEARRESTOR

DOOR GASKET

BASE-RING

FIGURE 29.

3.Reassemble following the procedure under "Replacing the Manifold/Burner Assembly".

Explosion Hazard

•Tighten both manifold door screws securely.

•Remove any fiberglass between gasket and combustion chamber.

•Replace viewport if glass is missing or damaged.

•Replace two piece wire connector if missing or removed.

•Replace door gasket if damaged.

•Failure to follow these instructions can result in death, explosion, or fire.

,Check the door gasket for damage or imbedded debris prior to installation.

,Inspect the view port for damage and replace as required.

,Insert the manifold/burner assembly into the burner compartment making sure that the tip of the manifold tube engages in the slot of the bracket inside the combustion chamber (Figure 30).

,Inspect the door gasket and make sure there is no

fiberglass insulation between the gasket and the combustion chamber.

,Replace the two screws, which secure the manifold/ burner assembly door to the combustion chamber and tighten securely. Once the manifold/burner assembly door is tightened, visually inspect the door gasket between the manifold/burner assembly door and the combustion chamber for spaces or gaps that would prevent a seal. IMPORTANT: Do not operate the water heater if the door gasket does not create a seal between the manifold door and the combustion chamber.

,Reconnect the two wire leads to the thermal switch, the manifold tubing, pilot tubing, and thermocouple to the gas control valve/thermostat. NOTE: L.P. gas systems use reverse (left-hand) threads on the manifold tube. Do not cross-thread or apply any thread sealant to these fittings. The thermocouple nut should be started and turned all the way in by hand. An additional quarter turn with a 7/16" open-end wrench will then be sufficient to seat the Iockwasher.

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