Pilot Light Won't Stay Lit in Tempe

This guide walks through the likely culprits in order, with notes on which ones are safe DIY checks and which ones mean stepping back and calling a professional. Gas appliances deserve caution, so when something feels off, trust that instinct.

Thermocouples wear out. After years in a hot flame, the sensor weakens and stops generating enough current to hold the valve open, even though the pilot flame looks perfectly fine. This is the most common reason a pilot lights but will not stay lit, and it is a routine, inexpensive repair.

A weak thermocouple sometimes shows early symptoms before it fails completely. The pilot may stay lit for hours and then die overnight, or it may need several attempts before it catches and holds. If your pilot's behavior has been getting flakier over weeks, the thermocouple is almost certainly the story. A dead pilot means no hot water, and our guide to no hot water causes and fixes in Tempe covers the other suspects when the pilot checks out fine.

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Tempe water heaters usually live in garages, and garages are drafty. A strong gust, especially during monsoon season when winds whip through open garage doors, can blow a pilot out. If your pilot problems started during a windy stretch, a draft may be the whole story.

Check whether the draft is normal garage airflow or something new, like a vent cap that blew off or a garage door that no longer seals. Persistent drafts can also signal a venting problem, which matters because proper venting carries combustion gases safely outside. When in doubt about venting, bring in a professional rather than experimenting.

Dust, spider webs, and corrosion can partially block the pilot orifice, producing a weak, wavering flame that cannot heat the thermocouple properly. Garages collect dust, and Arizona dust storms add to it, so a dirty pilot assembly is more common here than in cleaner indoor installations.

A weak yellow flame instead of a strong blue one points to a dirty orifice or low gas pressure. Cleaning a pilot assembly involves disassembly around gas components, which is why many homeowners prefer to let a technician handle it. It is a quick service visit, and the tech can inspect the burner and thermocouple at the same time. If you also notice a water heater leaking at the base, treat the leak as the more urgent problem, and a visit for gas water heater services covers the pilot, thermocouple, and burner in one trip.

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If the pilot will not light at all, not even briefly, check the gas supply before assuming the worst. Make sure the gas valve to the water heater is fully open and that other gas appliances in the home are working. If nothing gas works, the issue is with the supply, not the water heater.

Never try to force gas flow or bypass safety controls. If you smell gas at any point, leave the area and call for help from outside the home. Gas supply issues beyond a closed valve are strictly professional territory.

If you recently had other gas work done, like a new stove or dryer installation, a valve may have been left partially closed. Trace the gas line from the meter to the water heater and confirm every valve handle runs parallel to the pipe, which means fully open.

A single thermocouple replacement on a mid life unit is a no brainer. But repeated pilot problems on a water heater that is 8 to 10 years old tell a different story. Aging gas controls, corroded burners, and worn valves tend to fail in sequence, and each service visit buys less time than the last.

If your unit is in that age range and the pilot is just the latest complaint, read up on flushing a water heater in Tempe hard water and the other maintenance your tank may have missed. Sometimes the honest math favors putting repair money toward a replacement instead of nursing an old unit through another summer.

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