White Rodgers 37C72U Removing OLD Control, Special Installation Note, Installing NEW Control

INSTALLATION

REPLACEMENT INFORMATION

REMOVING OLD CONTROL

1.Shut off gas to water heater.

2.Shut off water at cold water inlet.

3.Connect hose to heater drain cock. Drain water to a nearby drain. Open a hot water faucet for faster drain- ing.

4.Disconnect gas line at union (figure 1). Remove piping from old control.

5.Disconnect the:

a.Thermocouple (left side).

b.Pilot burner (small tube on the right side)

c.Main burner (large tube in the middle).

6.Remove the control by turning it counterclockwise

( ). If needed, a short piece of 1/2” black iron pipe can be screwed into the control inlet to increase lever- age.

SPECIAL INSTALLATION NOTE

If replacing a Unitrol or Robertshaw control, install exten- sion adaptor fitting provided into the outlet of the control.

Gas supply pipe

Gas shut-off

valve

Union

(metal-to-metal)

Tee

Drip leg

(sediment trap)

Pipe cap

					PI
					LIG	LO
						T
					HTI
						N
						G
R	Y	T		HOTTER
E	O		WATER
V	H		WITH	INCREASES		L
C			SCALDING			O
			CAUTION:			W
B
			A

To pilot burner

To main burner To thermocouple

INSTALLING NEW CONTROL

All piping must comply with local and state ordinances or with the National Fuel Gas Code (ANSI Z223.1–NFPA 54), whichever applies.

Dirt or contamination in the gas line can block the control from operating creating a risk of explosion, injury or death. To protect the control from dirt/contamination, a drip leg or sediment trap (see Figure 1) must be installed in the piping leading to the control.

1.Apply pipe joint compound to the male threads of control, leaving the first two or three threads clean.

2.Install control in tank. Turn clockwise (). Use a short piece of pipe to help in turning. Align the control so that burner and pilot tubes may be connected.

NOTE

This control is equipped with LEFT-HAND threads on the outlet of the control. Check the fitting on the burner assem- bly to make sure the threads are also the LEFT-HAND type. If the threads are not LEFT-HAND type, return the control to the dealer and obtain an LP gas control with RIGHT-HAND threads on the outlet.

3.Make burner, pilot, and thermocouple connections. Do not use pipe joint compound or teflon tape. Thermo- couple nut should be hand tightened and then turned an additional 1/4 turn with a small wrench. DO NOT OVER-

TIGHTEN.

Figure 1. Typical gas connection

4.Connect gas line. Use new black iron pipe that has been properly reamed. If old pipe is used, be sure it is clean and free from rust and scale. Use pipe joint compound on male threads only. (Use a pipe joint compound approved for natural gas service.) Do not use TEFLON tape. Do not apply compound to first two threads.

5.DO NOT use joint compound or tape on the union connection.

6.To fill the water heater with water:

a.Close the water heater drain valve by turning the handle to the right (clockwise). The drain valve is on the lower front of the water heater.

b.Open the cold water supply valve to the water heater.

NOTE

The cold water supply valve must be left open when the water heater is in use.

c.To ensure complete filling of the tank, let air exit by opening the nearest hot water faucet. Allow water to run until a constant flow is obtained. This will let air out of the water heater and the piping.

d.Check all new water piping for leaks. Repair as needed.

2