How to Repair a Rheem Water Heater  

Repairing your own Rheem gas water heater requires some do-it-yourself skill. Just following the manual does not always cut it. Whether you are replacing Rheem water heater thermostat, Rheem heater gas control valve, or simple cleaning your Rheem water heater burner assembly; here are a few tips may prove helpful. These are tips from the field, you should always follow the manufactures instructions when working on or installing a new gas appliance. 

How to Replace the Thermocouple on a Rheem Gas Water Heater 

1.      Turn the gas control knob on top of the gas control valve to its off position. For safety, turn off the gas supply valve feeding the water heater.  

2.      Remove the outer burner chamber door. Disconnect the pilot tube, main burner tube and thermocouple from the Rheem gas control valve with a small adjustable wrench. Remove the inner burner chamber door. 

3.      Install a new Rheem thermocouple through the inner door and into position nest to the pilot orifice. 

4.      Install a new seal on the inner door and reinstall. 

5.      Reconnect the pilot and main burner tube to the Rheem heater gas valve, and then the thermocouple. Turn the gas supply back on to the control. Light the pilot and turn the gas control knob on. Check the tube connections with a liquid leak detector. If leaks detected, immediately turn the gas supply off and reseal all connections to the Rheem gas control valve.   

Cleaning the Burner on a Rheem Gas Water Heater 

1.      Turn off the main gas supply to the waterheater thermostat control.  Set the gas control knob to ‘Off’. Rotate the temperature dial to vacation. 

2.      Disconnect the burner, pilot and thermocouple from the control valve. 

3.      Remove the front cover and inner burner cover.  

4.      Pull the burn assembly straight out of the water heater. 

5.      Vacuum the inner burner chamber inside the water heater with a shop-vac. 

6.      Turn the burner assembly upside down over a waist receptacle and shack it back and forth to remove any buildup. Vacuum the burner to remove smaller partials of debris. 

7.      Replace the Rheem water heater thermocouple while you have the burner assembly out.  

8.      Install a new Rheem combustion chamber seal, and then reinstall the burner assembly and inner door. 

9.      Reconnect the burner, pilot and thermocouple to the gas valve. 

10.  Follow the Rheem water heater lighting instruction.  

How to Install a New Rheem Water Heater Thermostat 

1.      Close the main gas supply valve. 

2.      Drain all the water from inside the water heater tank. Connect a garden hose to the drain valve. Run the open end of the hose to a floor drain. Open the drain valve and let the water run under pressure it flow freely. Caution- the water may still be very hot. 

3.      Disconnect the gas, pilot and thermocouple from the thermostat. Shut off the main water supply to the Rheem heater. Open the (T&PR) Temperature and pressure relief valve to allow the water to drain. If you do not open the relief valve, the tanks will air lock and not drain. 

4.      Unscrew the Rheem thermostat with a large pipe wrench. Turn the gas control valve counterclockwise to remove. 

5.      Wrap the male threads of the new Rheem thermostat with several rounds of thread tape. 

6.      Screw the new gas valve into the tank and secure it with your pipe wrench. Line up the new control with burner fittings. 

7.       Reconnect the gas burner tube, pilot supply tube and thermocouple to the new Rheem gas control thermostat.  

8.      Close the T&PR valve and drain valve. Disconnect the drain hose from the water heater. 

9.      Turn the main water supply back on. Open the hot water faucet in the bathtub to allow all the air to escape from the filling water heater. When water-not air- is flowing freely from the hot water faucet in the bathtub, close the tub faucet.  

10.   Open the waters gas valve and light the water heater according to the manufactures instruction label.