Why Does the Pilot Light Go Out on a Water Heater?

There’s nothing worse than stepping into the shower, expecting a nice hot blast of water, and instead getting hit with an ice-cold reality check. If you’ve been asking, “Why does the pilot light go out on a water heater?”, you’re not alone. This is one of the most common (and annoying) water heater issues homeowners face.

The good news? It’s usually fixable. The bad news? Ignoring it could mean a long-term headache, higher energy bills, and even safety risks. Let’s break down the reasons, the fixes, and how to prevent this from becoming a regular problem.

The Big Question: Why Does the Pilot Light Go Out on a Water Heater?

If your pilot light keeps going out, it’s usually due to one of the following:

• A faulty thermocouple – This tiny but mighty component senses the pilot light’s flame. If it’s dirty, bent, or just broken, it’ll shut off the gas supply, killing the flame.
• A clogged pilot tube – Dirt and debris can block the small opening where gas flows to the pilot light, making it difficult to stay lit.
• A draft or airflow issue – If the flame goes out suddenly, a drafty room or poor ventilation could be to blame.
• Gas supply issues – If gas isn’t reaching the pilot light consistently, it won’t stay on. A partially closed gas valve or a larger supply issue may be the culprit.
• A failing gas control valve – This is the big boss of your water heater’s gas flow. If it’s malfunctioning, the pilot light won’t stay lit.

Now that we know why this happens, let’s get into how to fix it.

Quick Fixes: How to Get Your Pilot Light to Stay On

Before you call a plumber (or start shopping for a new water heater in a panic), try these solutions:

1. Clean or Replace the Thermocouple

• Turn off the gas supply and let the water heater cool down.
• Locate the thermocouple—it’s the thin metal rod positioned near the pilot flame.
• If it’s dirty, gently clean it with steel wool or fine sandpaper.
• If it’s bent away from the flame, carefully adjust it back into position.
• If it looks damaged, replacing it is usually a cheap and easy fix.

2. Unclog the Pilot Tube

• Turn off the gas and wait for the heater to cool.
• Use a thin needle or compressed air to clear out any debris in the tube.
• Try relighting the pilot light and see if it stays on.

3. Check for Drafts

• Close nearby windows and doors.
• Look for gaps or openings near your water heater that could be letting in airflow.
• If the water heater is in a basement or garage, consider installing a draft guard.

4. Inspect the Gas Supply

• Make sure the gas valve is fully open.
• If other gas appliances in your home are working fine, the issue is likely with the water heater.
• If none of your gas appliances are working, call your gas provider immediately.

5. Test the Gas Control Valve

• If everything else checks out but the pilot still won’t stay lit, the gas control valve may be failing.
• Unfortunately, this is not a DIY fix. Call a professional to inspect and replace it if needed.

Why Does My Water Heater Pilot Light Keep Going Out?

If this isn’t a one-time issue and your pilot light keeps going out, it might be time to dig deeper:

• Older water heaters naturally have more issues – If yours is 10+ years old, it might be nearing the end of its life.
• Thermocouples wear out over time – Even if it worked fine last year, it might need replacing now.
• Gas line pressure can fluctuate – If you live in an area with inconsistent gas pressure, this could cause repeated pilot light failures.
• Rust and corrosion can block the gas line – If your water heater hasn’t been serviced in a while, buildup could be affecting performance.

Regular maintenance and cleaning can go a long way in preventing repeated failures.

Fun Fact: Your Water Heater Can Be a Silent Money Pit

Did you know that a malfunctioning water heater can skyrocket your energy bills? A pilot light that keeps going out means your heater isn’t running efficiently. If it struggles to stay lit, it might be using more gas than necessary. In short, a faulty water heater isn’t just an inconvenience, it’s a money drain.

Final Thoughts

A pilot light that won’t stay lit is frustrating, but it’s often a sign of a small issue rather than a major disaster. Cleaning or replacing the thermocouple, clearing the pilot tube, and ensuring proper gas flow can usually solve the problem. If not, a professional can help diagnose and fix it before it leads to bigger issues.

Regular maintenance can help you avoid cold showers, high energy bills, and unnecessary stress. If your water heater is acting up often, it might be time for a professional checkup, or even an upgrade to a newer, more efficient model.

FAQs

1. Can I replace a thermocouple myself?

Yes, if you’re comfortable with basic DIY repairs. Thermocouples are cheap (usually under $20) and easy to replace with a wrench and screwdriver. Just make sure the gas is off before starting.

2. How often should I check my pilot light?

It’s a good idea to check it every few months, especially before winter. If your heater is acting up, inspect it immediately.

3. What if I smell gas near my water heater?

Stop everything and get out. A gas leak is dangerous. Call your gas provider or emergency services immediately.

4. Is it worth fixing an old water heater?

If your unit is over 10 years old and constantly having problems, replacing it might be more cost-effective than repeatedly fixing it.

5. Can a water heater pilot light go out during a power outage?

Nope! Gas water heaters with pilot lights don’t rely on electricity, so a power outage won’t affect them. However, modern electronic ignition water heaters might need resetting after an outage.