A.O. Smith Water Heater Replacement Parts, Removing the Burner from the Manifold/ Burner Assembly

Temperature and Pressure Relief Valve

Explosion Harzard

Temperature-pressure relief

valve must comply with ANSI Z21.22-CSA 4.4 and ASME code.

•Properly sized temperature- pressure relief valve must be installed in opening provided.

•Can result in overheating

and excessive tank pressure.

•Can cause serious injury or death.

Manually operate the temperature and pressure relief valve at least once a year to make sure it is working

Replacement Parts

IMPORTANT: The following maintenance procedures are for the FVlR System components and should be performed by a qualified technician.

Replacement parts may be ordered through your plumber or the local distributor. Parts will be shipped at prevailing prices and billed accordingly. When ordering replacement parts, always have the following information ready:

1.model, serial, and product number

2.type of gas

3.item number

4.parts description

See Repair Parts Section for a list of available repair parts.

Removing the Manifold/Burner Assembly

1.Turn off the gas supply to the water heater at the manual gas shut-off valve. This valve is typically located beside the water heater. Note the position of the shut-off valve in the open/on position then proceed to turn it off (Figure 3).

2.On the lower front of the water heater locate the gas control valve/thermostat (see Figure 23). Before per- forming any maintenance, it is important to turn the temperature dial on the gas control valve/thermostat to its lowest setting.

3.On top of the gas control valve/thermostat turn the gas control knob to the "OFF" position. NOTE: On the Rob- ertshaw gas control valve/thermostat the dial stop must first be depressed before turning the gas control knob (Figure 19).

WHITE RODGERS GAS VALVE ROBERTSHAW GAS VALVE

properly. To prevent water damage, the valve must be properly connected to a discharge line which terminates at an adequate drain. Standing clear of the outlet (discharged water may be hot), slowly lift and release the lever handle on the temperature and pressure relief valve to allow the valve to operate freely and return to its closed position. See Figure 21. If the valve fails to completely reset and continues to release water, immediately shut off the manual gas control valve and the cold water inlet valve and call a qualified technician.

TEMPERATURE AND PRESSURE RELIEF VALVE

A I / MANUALRELIEF

T ZVALVE

DISCHARGE LINE TO DRAIN

FIGURE 21.

4.Remove the outer door.

5.Remove the two screws securing the manifold door assembly to the combustion chamber (Figure 23).

	GAS CONTROL		VALVE/
	THERMOSTAT
I	\			.	PtEZO
		t	_ _IGNITER	I	BUTTON
I		_. Liai==ji_
MANIFOLD_L		_ _. 1		I
TUBE				-P'L°T
THERMOCOUPLEI--ITUBE- I '(
I		\_I/, _' -		I	THERMAL
VIEW PO RT'I_{_)L_/I'_					SWITCH
I	•				MANIFOLD
					DOOR
/	/		/\		I
MANIFOLD_			\ TWO	PIECE
SCREWS (2)			WIRE	CONNECTOR

FIGURE 23.

,Disconnect the thermocouple (right-hand thread), pilot tube, the igniter wire from the igniter button, the two connectors attached to the thermal switch, and manifold tube at the gas control valve/thermostat. (Figures 22

&23.) NOTE: L.R Gas systems use reverse (left-hand) threads on the manifold tube.

7.Grasp the manifold tube and push down slightly to free the manifold, pilot tube, and thermocouple.

8.Carefully remove the manifold/burner assembly from the burner compartment. NOTE: Be sure not to damage internal parts.

T'LBOT

THERMOCO_PLE_._

MANIFOLD TUBE MANIFOLD TUBE

FIGURE 22.

Removing the Burner from the Manifold/ Burner Assembly

Natural Gas (Low Nox) & L.P. Gas Burner

1.Take off the burner by removing the two (2) screws lo- cated underneath the burner.

25