Why does my Atwood water heater pilot light go out as soon as I release the pilot knob?

This is most commonly caused by a faulty or weak thermocouple. The thermocouple is a safety device that senses the pilot flame and keeps the gas valve open. If it's worn out, corroded, or improperly positioned in the flame, it won't generate enough voltage to hold the gas valve open, causing the pilot to extinguish as soon as you release the knob.

How do I check if the thermocouple on my Atwood water heater is bad?

First, visually inspect the thermocouple tip to ensure it is positioned directly in the pilot flame. If it looks corroded, bent away from the flame, or damaged, it likely needs replacement. You can also use a multimeter to test the thermocouple's output; it should read between 20-30 millivolts when heated by the pilot flame. Anything below 20 millivolts typically means it needs to be replaced.

Could a dirty pilot tube or orifice cause the pilot to not stay lit on my Atwood water heater?

Yes, a clogged or partially blocked pilot tube or orifice can produce a weak or inconsistent pilot flame that doesn't adequately heat the thermocouple. Use compressed air or a fine needle to carefully clean out any debris, spider webs, or insect nests from the pilot tube and orifice. After cleaning, relight the pilot and verify the flame is steady and blue, fully enveloping the thermocouple tip.

Can wind or drafts cause my Atwood RV water heater pilot to keep going out?

Absolutely. Since RV water heaters are externally vented, wind gusts can blow out the pilot flame, especially if the exterior door screen or wind baffle is damaged or missing. Inspect the outside access door for a proper wind screen and ensure it is intact and correctly installed. Also check that the burner tube and combustion chamber are properly sealed so crosswinds cannot disrupt the flame.

Are there other components besides the thermocouple that could prevent the Atwood pilot from staying lit?

Yes, a faulty gas control valve (ECO valve) can fail to stay open even with a functioning thermocouple. Low propane tank pressure, a partially closed supply valve, or an air lock in the gas line can also starve the pilot of fuel. Additionally, check that the reset button on the ECO (Energy Cut-Off) switch hasn't tripped due to overheating, as this will shut off gas flow entirely until manually reset.

Atwood Water Heater Pilot Won't Stay Lit — RV Diagnostic Guide

Probable Causes

The most common reason an Atwood water heater pilot won't stay lit is a failed or weak thermocouple (or ECO/thermal cutoff). Other likely causes include:

Dirty or clogged pilot orifice restricting gas flow
Faulty gas control valve (not reading the thermocouple signal properly)
ECO (Emergency Cut-Off) tripped or failed — the reset button on the back of the unit
Loose thermocouple connection at the gas valve
Wind or drafts entering the burner chamber through a damaged exterior door or gasket
Low propane supply or partially closed valve upstream

Urgency & Safety

Moderate to High. Any issue involving propane and an open flame warrants prompt attention. Do not repeatedly attempt to relight if you smell gas. If the pilot lights but dies immediately upon releasing the knob, it is likely a thermocouple issue and not an active gas leak — but always verify. Never bypass the thermocouple or ECO. Ensure your LP detector and CO detector are functional before troubleshooting.

DIY Difficulty

Beginner to Intermediate. Checking the ECO reset, cleaning the pilot orifice, and replacing a thermocouple are all manageable for a handy RV owner with basic tools. Replacing the gas control valve is more advanced.

Typical Repair Cost

| Repair | DIY Cost | Shop Cost | |---|---|---| | Thermocouple replacement | $10–$25 | $75–$150 | | Pilot orifice cleaning | $0–$5 | $50–$100 | | ECO reset/replacement | $15–$30 | $75–$125 | | Gas control valve replacement | $80–$150 | $200–$350 |

Parts You May Need

Atwood thermocouple (match your model — commonly 93868 or equivalent)
Pilot orifice assembly
ECO thermal cutoff switch
Gas control valve (if all else fails)
7/16" and 3/8" wrenches, needle-nose pliers, compressed air

Step-by-Step Diagnosis

Check propane supply. Confirm your tank is not empty and the main valve plus the individual appliance valve are fully open. Try running your stove to verify gas flow to the coach.

Reset the ECO. Access the rear of the water heater from outside the RV. Locate the small reset button on the ECO switch (mounted on the inner tank wall near the gas line). Press it firmly. A tripped ECO is the single most overlooked cause of this problem.

Attempt to light the pilot. Turn the gas control knob to PILOT, press and hold it down, then ignite. Hold the knob down for a full 60 seconds before releasing. Many owners release too early — the thermocouple needs time to heat up.

Inspect the thermocouple position. The tip of the thermocouple must sit directly in the pilot flame. If it has shifted, bend it gently back into position so the flame fully envelops the tip.

Check the thermocouple connection. At the gas control valve, snug the thermocouple fitting with a 7/16" wrench. It should be finger-tight plus a quarter turn — do not over-torque.

Clean the pilot orifice. Remove the pilot assembly and blow compressed air through the orifice. Do not ream it with a wire or drill bit, as this can enlarge the opening and create a dangerous condition.

Test the thermocouple. With a multimeter set to DC millivolts, light the pilot and measure output at the thermocouple leads. You should see 8–30 mV. Below 6 mV, replace it.

Check for drafts. Inspect the exterior door, door gasket, and burner tube for damage or gaps that allow wind to blow out the pilot.

Evaluate the gas control valve. If the thermocouple tests good, the ECO is fine, and the pilot flame is strong and properly positioned, the gas valve itself is likely not holding the magnet open. Replace the valve.

When to Call a Technician

Call a certified RV technician if you smell gas at any point during diagnosis, if the pilot flame appears yellow or erratic after cleaning, if the gas control valve needs replacement and you're not comfortable working with gas fittings, or if you've replaced the thermocouple and ECO and the problem persists. Any time you're unsure, err on the side of professional service — propane mistakes can be catastrophic.

Atwood Water Heater Pilot Won't Stay Lit

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