As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
BOS - FLT 6429 - AFTER DEPARTURE FROM BOS, CREW GOT A RIGHT AIR VALVE FAIL LIGHT. AIRCRAFT DIVERTED BACK TO BOS AND LANDED WITHOUT INCIDENT. MAINTENANCE REPLACED THE ANTI-ICE START BLEED VALVE WHICH WAS STICKING, AND THE AIR VALVE FOR PRECAUTIONARY REASONS. (M)