I can not light the pilot on my reliance sta-kleen 502 (30 gallon) waterheater. please help

Reliance is Rheem
Replace thermocouple is best start point.
Example Whirlpool manual shows general replacement steps on page 22:
Buy thermocouple at hardware or home center. measure length before going to store.
http://waterheatertimer.org/pdf/Whirlpool-6510397.pdf

Utube videos show how to replace thermocouple

Many things can affect pilot:
Low gas pressure, Water or air or debris in the gas control valve, High-heat event causing ECO to trip requiring new gas control valve, burner and tubes needing clean-out, FV sensor tripped, loose or bad thermocouple.
Manual above shows general steps for doing some of these things, but service technician is probably best choice if thermocouple does not fix problem.

Gas water heaters require periodic maintenance.
If repairs cost more than $330, then buy new gas water heater and install yourself.
Use the old one for a solar collector.
http://waterheatertimer.org/How-to-install-gas-water-heater.html

Upvote the help.
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