Replace the pilot assembly when intake filter cleaning + thermocouple replacement haven't resolved "pilot won't stay lit." Bradford White pilot assemblies cost $60-$120; 45-minute DIY.
Replacement procedure
- Shut off gas, wait 5 minutes
- Open burner access door
- Disconnect thermocouple, pilot gas tube, ignition wire at gas valve
- Remove pilot assembly mounting screws
- Pull pilot out, noting orientation
- Install new assembly in same orientation
- Reconnect at gas valve
- Restore gas, relight per our lighting guide
Cleaning a dirty pilot (often skips replacement)
- Compressed air through pilot tube
- Thin wire (paper clip) to clear orifice
- Reconnect, restore gas, relight
Bottom line
$60-$120 part, 45-min DIY. Try cleaning first, then replace. For broader troubleshooting see troubleshooting hub.