The situation
Illustrative example. Not a real job or customer.
A Brea household's garage gas water heater loses its pilot every few days through the cooler months. They relight it using the label instructions, it runs for a while, then goes out again. There is no gas smell, but the bottom of the heater is surrounded by stored boxes and a dryer stands nearby.
- The owner keeps a short symptom log: dates, whether the garage door was open, and whether the dryer had been running.
- They notice the pilot goes out most often after laundry days.
- They clear the boxes away from the heater and call a licensed plumber.
- The plumber finds lint packed into the heater's air intake screen and a thermocouple that no longer holds the gas valve open reliably.
The plumber cleans the intake per the manufacturer's instructions, replaces the thermocouple and checks the vent's draft. The owner moves storage away and keeps the area around the intake clear.
What was going on
Many gas water heaters draw combustion air through a screen near the base. Lint from a nearby dryer, dust and pet hair can clog it, starving the burner of air. The heater's safety system then shuts it down. On older models, a worn thermocouple adds to the problem by dropping the pilot even when air is fine.
The log was the key in this example. Linking outages to laundry days pointed the plumber toward air supply before replacing parts at random.
Where this could have gone differently
- IfThe owner had smelled gasThenThe right move is to leave and call 911 or SoCalGas from outside, not to relight.
- IfScorch marks had appeared at the burner doorThenThat suggests flame rollout; the heater should stay off until a plumber finds the cause.
- IfThe vent was disconnectedThenExhaust could spill into the garage; the heater stays off until repaired.
- IfThe heater were very oldThenThe plumber might have discussed replacement instead of parts.
Lessons from the example
Questions to ask in a similar situation
- Is the air intake clean?
- Is the thermocouple or flame sensor working?
- Is the vent drawing properly?
- Is anything nearby, like a dryer, affecting the heater?
Common questions
Is this based on a real customer?
No. It is an invented example to explain a common cause of pilot outages.
Can a dryer affect a water heater?
Lint from a nearby dryer can clog a gas heater's air intake. Keep the area clean and the intake clear.
How many times should I relight a pilot?
If it goes out again soon after relighting, stop and have it checked by a licensed plumber.
General information for Brea, not a quote or professional advice. In an emergency, call 911.