Why Won't My Hot Water Heater Light?: 1 Minute to Troubleshoot Your Water Heater Issues

If your hot water heater won't light, it can be a frustrating experience—especially when you need hot water most. There are several potential reasons behind this issue, and pinpointing the root cause will help you determine the best solution. The most common culprits include problems with the pilot light, thermocouple, gas supply, or electronic ignition system.

The pilot light is a small, continuously burning flame that ignites the gas burner in most traditional water heaters. If this light goes out, your heater won’t produce hot water. Sometimes, a draft, dirty thermocouple, or malfunctioning gas control valve can extinguish the pilot. If you have a newer, electronic ignition model, ignition failures might stem from issues with the igniter or control board. Gas supply interruptions—like a closed or faulty gas valve—can also prevent your heater from lighting.

As a designer who’s seen many home layouts, I’ll point out that sometimes simple environmental factors impact your water heater’s performance. For example, poor ventilation or awkward placement can lead to pilot light outages due to drafts or dust accumulation. When planning your utility area, consider accessibility and airflow—not just appearance. If you’re imagining a remodel or building from scratch, integrating a utility-friendly solution with designated spaces for appliances makes troubleshooting and maintenance much easier. Tools like a room planner can help you visualize and optimize appliance placement before you commit to a layout.

Tips 1:

Check your user manual for lighting instructions specific to your water heater model. If you smell gas or suspect a leak, shut off the gas supply and contact a professional. Regular inspection and proper placement can help prevent many common problems with hot water heaters.

FAQ

Q: Why does my hot water heater's pilot light keep going out?

A: The pilot light may go out due to a faulty thermocouple, a draft, accumulated dust, or a malfunctioning gas valve. Addressing these issues usually resolves the problem.

Q: How do I know if my thermocouple is bad?

A: If your pilot light won’t stay lit, the thermocouple could be to blame. This safety device senses heat from the pilot—if it’s not working, gas flow is stopped for safety reasons.

Q: Can low gas pressure affect my water heater lighting?

A: Absolutely. If there’s not enough gas pressure, the pilot or igniter may not work properly. Check that your gas valve is fully open and consult a professional if you suspect a supply problem.

Q: Should I try to repair my water heater myself?

A: For basic issues like relighting the pilot, follow your manufacturer’s instructions. For anything involving gas or electrical parts, professional help is safer and often required.

Q: How does water heater placement affect performance?

A: Poor placement can expose your water heater to drafts or restrict airflow, increasing the risk of pilot outages and other issues. Proper utility layout design improves both function and maintenance access.