Water Heaters · Gas Components
Thermocouple
A safety device in gas water heaters that generates electricity from heat to keep the gas valve open, shutting off gas if the pilot light goes out.
Common uses
Pilot light safety, gas control, flame sensing
Common symptoms
- Pilot won't stay lit
- No gas flow
- Cold water only
Common repairs
- Thermocouple replacement
- Connection cleaning
- Gas valve service
Related terms
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