How to replace a thermocouple on a gas water heater

Are you questioning how to replace a thermocouple on a gas water heater? and you find it difficult to replace it? Here is what to do

we’re going to explain how to replace the element of a gas water heater especially the thermocouple and thermopile and other elements, moreover, we’re going to show you how to test all these elements step by step

please follow these instructions and steps to know how to replace a thermocouple on a gas water heater and other elements and how to test them:

How to replace a thermocouple on a gas water heater step by step

1. CLOSED CIRCUIT THERMOCOUPLE TESTING (White Rodgers Control)

Step 1. Closed-circuit testing is a popular technique for testing thermocouples. Following the lighting instruction label on the heater, proceed to gentle the pilot and permit it to function for 3 minutes.

If the pilot is not going to keep lit, maintain the pilot button (situated on the mix thermostat/gas valve) down throughout this check

Step 2. Using a multimeter able to measure millivolts, join one lead utilizing an alligator clip to the copper sheath of the thermocouple, use the second lead of the multimeter to probe the highest terminal situated behind the mixture thermostat/gas valve.

Step 3. If the meter reads 10 millivolts or greater, the thermocouple is OK. If studying is beneath 10 millivolts, change the thermocouple.

2. CLOSED CIRCUIT THERMOCOUPLE TESTING (Robertshaw Control)

Step 1. Disconnect thermocouple from mixture thermostat/gas valve.

Step 2. Connect a thermocouple adaptor (BWC P/N 239-44642-00, Robertshaw P/N 75036) on the thermocouple location within the combination thermostat/gas valve.

Step 3. Reconnect the thermocouple to the adaptor. Make sure all connections are tight (finger tight plus ¼ flip)

Step 4. Using a multimeter able to measure millivolts, connect one alligator clip to the set screw of the adaptor, and the opposite alligator clip to the copper portion of the thermocouple.

Step 5. Following the lighting instruction label on the heater, proceed to light the pilot and allow it to function for 3 minutes. If the pilot is not going to keep lit, maintain the red reset button (positioned on the mix thermostat/gas valve) down during this test

Step 6. If the meter reads 13 millivolts or larger, the thermocouple is OK. If studying is under 13 millivolts substitute the thermocouple.

3. OPEN CIRCUIT THERMOCOUPLE TESTING (White Rodgers/Robertshaw Gas Valve)

Step 1. Disconnect thermocouple from mixture thermostat/gas valve.

Step 2. Using a multimeter able to measure millivolts, connect one alligator clip to the top ball or contact portion of the thermocouple, and the opposite alligator clip to a copper portion of the thermocouple.

Step 3. Following the lighting instruction label on the heater, proceed to mild the pilot and allow it to function for 3 minutes. It will probably be vital to carry the pilot button down constantly all through this take a look at. A studying of 20 to 30 millivolts signifies good thermocouple output.

4. THERMOCOUPLE REPLACEMENT (White Rodgers/Robertshaw Gas Valve)

Step 1. Turn off the fuel provide to the water heater. Rotate knob of combination thermostat/gas valve to “OFF” place.

Notes:

For White Rodgers Control, depress the knob barely and rotate clockwise to the “OFF” place.

For Robertshaw Control, rotate the knob clockwise to the “OFF” place.

Step 2. Remove outer jacket door.

Step 3. Remove the suitable aspect of the internal door per SERVICE PROCEDURE RG-I, steps 3a using 3c.

Step 4. Disconnect the thermocouple from the mixture thermostat/gas valve. Locate one other finish of the thermocouple within the combustion chamber and take away it from the pilot bracket. Pull firmly pulling away from the pilot meeting.

Step 5. Install new thermocouple into pilot bracket guaranteeing the thermocouple is engaged into the pilot bracket. Position thermocouple in opposition to left side interior door flange at its unique place. Connect one other finish of the thermocouple to the combination thermostat/gas valve (finger tight + ¼ flip).

Step 6. Inspect inside door gasket per SERVICE PROCEDURE RG-I. Install proper side internal door per SERVICE PROCEDURE RG-. To resume operation comply with the directions situated on the lighting instruction label or the lighting directions positioned within the setup and operation handbook

5. OPEN CIRCUIT THERMOPILE TESTING (Honeywell Gas Control)

The following takes a look at what needs to be carried out whereas the pilot flame is on.

Step 1. Turn knob to pilot place and depress.

Step 2. Continue urgent knob and take away red (+) wire from resettable thermal door change.

Step 3. Using a multimeter able to measure millivolts, join the constructive aspect of the multimeter to the terminal of the resettable thermal door change. Connect the unfavorable side of the multimeter to any earth-ground location (jacket base, screw, and many others.).

Normal thermopile operation will likely be between 350mV – 850mV. If studying is lower than 350mV.

Step 4. If thermopile reading is between 350mV – 850mV, take away multimeter and reconnect the red wire to constructive (+) terminal of Gas Control.

Step 5. Release the Gas Control knob and switch to the specified setting to renew regular operation.

6. PILOT/ELECTRODE ASSEMBLY INSPECTION, CLEANING, AND REPLACEMENT

Step 1. Turn off the gas provide to the water heater. Rotate knob of gas management/gas valve to “OFF” place.

Step 2. Remove outer jacket door.

Step 3. Remove the correct side of the internal door per SERVICE PROCEDURE RG-I, steps 3a via 3c.

Step 4. Disconnect thermocouple/thermopile, pilot tube, and feedline from gas management/gas valve.

NOTE: Feedline nut for pure gasoline management makes use of right-hand threads, LP management makes use of left-hand thread.

Step 5. Disconnect piezo ignition wire from the piezo igniter.

Step 6. Remove burner meeting from the combustion chamber.

Step 7. Remove pilot/electrode assembly from the feedline

Step 8. Inspect pilot for the next:

1) Primary air openings for blockage. Must be free from any particles (grime, lint, and so forth).

2) Kinks or cracks within the pilot tube. If discovered, the pilot should be changed.

Step 9. Inspect pilot orifice:

1) Remove ½” nut from the underside of the pilot assembly.

2) Remove the pilot tube and pilot orifice.

3) Inspect the pilot orifice for blockage, should be cleaned or changed. (Honeywell pilot orifice not replaceable, substitute pilot assembly)

Step 10. Install pilot/electrode assembly to feedline, safe with the screw from step 7.

Step 11. Re-Install burner assembly into the combustion chamber, join feedline, pilot tube, and thermocouple/thermopile to gas management/gas valve.

Step 12. Install internal door per SERVICE PROCEDURE RG-I, steps Four via 13.

Step 13. To resume operation observe the directions positioned on the lighting instruction label or the lighting directions located within the setup and operation guide.

Notes:

For Honeywell Control, rotate the knob counter-clockwise to the “OFF” place.

For White Rodgers Control, depress the knob barely and rotate clockwise to the “OFF” position.

For Robertshaw Control, rotate the knob clockwise to the “OFF” place

Removal of a thermopile from Honeywell pilot assembly isn’t really useful, however may be achieved by viewing the pilot assembly from the highest and urgent the thermopile in the direction of the correct whereas pulling to take away.

7. PIEZO IGNITER, ELECTRODE TESTING, AND REPLACEMENT

With the pilot not in operation (no pilot flame), you possibly can examine the Piezo and electrode circuit by viewing the pilot through the sight glass situated on the inside door and observing the spark motion.

Step 1. Remove outer jacket door.

Step 2. Repeatedly depress the Piezo igniter while viewing the pilot through the sight glass. If a spark is current, the circuit is OK. If there isn’t a spark, proceed to step 3.

Step 3. Remove the orange (or white) wire from the Piezo igniter and set up a jumper wire as an alternative. Hold the opposite finish of the jumper by the wire insulation or utilizing an insulated instrument, after an unpainted floor such because the feedline or gas valve, and depress the Piezo igniter.

If there’s a spark, the igniter is OK, the pilot is just not functioning, and should be changed, see SERVICE PROCEDURE RG-III for pilot replacement. If no spark is current the igniter is just not functioning and should be replaced.

Step 4. For White Rodgers/Robertshaw gas valves: With orange wire disconnected from the piezo igniter. Using a typical screwdriver, place the blade of the screwdriver below the piezo bracket and gently pry the bracket from the entrance of the gas valve and unhook the bracket from the rear of the gas valve.

8. Gas Valve Testing and Replacement (White Rodgers/Robertshaw)

A gas valve is a nonrepairable machine. If troubleshooting has decided an issue with the fuel valve, it should be replaced.

If the burner and/or pilot don’t perform, service checks for gas strain, thermocouple output, magnet assembly, and ECO are to be carried out. If these verify OK, the fuel valve could also be defective

1) LINE PRESSURE

The gas valve is designed for the most line strain of 14.0″ w.c. and minimal line pressure of 1.0″w.c. over the water heater-rated manifold pressure (test ranking plate). Line strain should be checked with the burner on and burner off to guarantee correct readings.

2) MANIFOLD PRESSURE TESTING

(this process assumes a most line pressure of 14.0″ w.c.)

Step 1. Set gas valve to “OFF” place.

Step 2. Remove pressure faucet plug and set up stress faucet.

Step 3. Connect manometer to pressure faucet.

Step 4. Follow lighting directions and proceed to gentle the principle burner and observe manometer reading.

Step 5. The correct working vary for pure gas is 4.0 ±0.3″ W.C. Proper working vary for L.P. gas is 10.0 ±0.5″ W.C.

Step 6. If pressure is OK, set the gas valve to “OFF” take away the manometer and strain faucet and substitute the pressure faucet plug. Check for gas leaks earlier than putting the water heater again in operation. If pressure is out of the specification famous in step 5, proceed to step 7 or 8 for the correct service process.

Step 7. For White Rodgers control, the manifold pressure is just not adjustable. If the manifold strain is exterior the varies in step 5, the management should be replaced.

Step 8. For Robertshaw management, the manifold pressure is adjustable, proceed to step 9 for the adjustment process

Step 9. While the burner is in operation, take away the regulator entry cap to show the regulator adjusting screw. With a small screwdriver, rotate adjusting screw clockwise to extend stress and counter-clockwise to lower pressure.

Step 10. Replace regulator entry cap, set gas valve to “OFF”. Remove manometer and pressure faucet and change stress faucet plug. Check for gas leaks earlier than inserting the water heater again in operation.

3) ECO (Energy Cut Off) TESTING

Step 1. Disconnect the thermocouple from the gas valve.

Step 2. Using a multimeter able to measure Ohms (or continuity), connect one lead (alligator clip) to the pilot tube. Insert the opposite lead (probe) absolutely into the magnet opening, Be positive the probe makes contact only on the prime middle of the magnet opening. Do not permit the probe to make contact with the threaded sides of the opening.

Step 3. If continuity is indicated, the ECO is OK. If continuity is just not indicated, the ECO has opened and the gas valve should be changed.

9. COMBINATION THERMOSTAT/GAS VALVE REPLACEMENT

Step 1. Rotate the knob of the gas valve to the “OFF” place.

Step 2. Turn off the gas provide to the water heater.

Step 3. Disconnect the gas provide line from the gas valve.

Step 4. Turn off the water supply and drain the water heater fully.

Step 5. Remove outer jacket burner entry door.

Step 6. Right aspect interior door elimination.

1) Disconnect resettable thermal swap wire leads (main from gas valve) and take away wire tie from feedline.

2) Remove (2) hex drive screws from the suitable aspect interior door.

3) Remove (2) hex drive screws from the flange part of the interior door.

4) Remove the proper aspect interior door and put it aside. Be cautious to not injure gasket materials on the interior door

Step 7. Removal of the gas valve.

1) Disconnect essential burner feedline, pilot tube, and thermocouple from gas valve & take away the burner from the combustion chamber.

NOTE: Feed line nut for pure gas control makes use of right-hand threads, LP management makes use of left-hand thread.

2) Remove piezo bracket with piezo igniter (seek advice from SERVICE PROCEDURE RG-IV) from the gas valve.

3) Remove gas valve from the water heater, rotating counter-clockwise utilizing a control physique wrench or a size of ½” NPT pipe threaded into the inlet of control.

Step 8. Installation of the gas valve.

1) Install a brand new fuel valve using a management physique wrench or a size of ½” NPT pipe threaded into the inlet of control.

DO NOT OVERTIGHTEN. Use warning to not injure the forged aluminum physique of the fuel valve. Be sure to not injure the bundled wire leads.

Note: The gas valve has to be put in within the correct upright place to guarantee the feedline will align correctly on the interior door flange.

DO NOT OVERTIGHTEN. If management is turned previous correct alignment, don’t reverse the path to align.

2) Reattach Piezo bracket with Piezo igniter to the gas valve.

3) Reattach the principle burner feedline, pilot tube, and thermocouple to the gas valve.

NOTE: Feedline nut for pure gas control makes use of right-hand threads, LP control makes use of left-hand thread.

4) Gather wire leads of the fuel valve and Piezo igniter and safe alongside feedline utilizing new wire tie offered.

5) Connect fuel provides piping to the inlet of management. Use again up wrench on wrench boss of control, by no means use on the physique of control.

Step 9.

Reinstallation of the interior door meeting.

Before reinstallation of the interior door, totally examine the interior door gasket for the next:

> Tears.

> Missing Material.

> Cracks.

> Dirt or particles.

> Gasket Adhesion to internal door.

> Other imperfections that may inhibit correct seal.

> Material left on the combustion chamber.

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If the gasket just isn’t affected by any of the above, a gasket alternative won’t be required. If replacement is required, exchange utilizing a brand new gasket package following the instructions supplied with the package.