Rheem hot water tank (propane) pilot light will ignite, however once gas control knob is moved to ON and thermostat dial moved from Pilot Light to LOW, the burner flame quickly ignites and is extinguished?

Answer 1

1. Thermocouple Issue

The thermocouple detects whether the pilot light is on and signals the gas control valve to stay open. If it's dirty, damaged, or not positioned correctly in the pilot flame, it may shut off the gas supply when you turn the burner on.

Solution: Check the thermocouple for dirt or damage. Ensure it is positioned correctly in the pilot flame. If necessary, replace it.

2. Gas Control Valve

If the gas control valve is faulty, it may not maintain the gas flow to the burner, causing it to extinguish after ignition.

Solution: Test the valve for proper function. If it's malfunctioning, it may need to be replaced.

3. Insufficient Gas Supply

An inadequate gas supply can cause the burner flame to extinguish. This might be due to a clogged gas line or regulator issue.

Solution: Inspect the propane tank, gas lines, and regulator for clogs, leaks, or blockages.

4. Ventilation or Draft Issues

Poor ventilation or a downdraft can blow out the burner flame. Check the area around the water heater for obstructions or drafts.

Solution: Ensure proper ventilation and check for any blockages in the flue or venting system.

5. Pilot Assembly

A dirty or partially clogged pilot assembly can produce a weak flame that fails to properly ignite or sustain the burner.

Solution: Clean the pilot assembly using a brush or compressed air.

6. Overheating Protection

Many water heaters have a safety mechanism that shuts off the burner if the system overheats or detects an unsafe condition.

Solution: Check for proper water flow and ensure the thermostat is set to an appropriate temperature.

Steps to Diagnose and Fix:

1. Turn off the gas supply.

2. Inspect and clean the thermocouple, pilot assembly, and burner.

3. Check the gas control valve for functionality.

4. Test the gas supply and regulator for consistency.

5. Reassemble and test the system.

If these steps do not resolve the issue, consult a licensed technician to avoid safety risks.