As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTS SMOKE & ODOR FROM FWD AFT LAVATORY UNDER SINK AREA. SMOKE WAS WHITE WITH ACRID ELEC TYPE SMELL. FLIGHT ATTENDANT DISCHARGED A HALON EXTINGUISHER UNDER SINK AT WATER HEATER & TOWARD AFT AREA OF COMPARTMENT. NO CB'S TRIPPED IN FLIGHT DECK. INSPECTED LAVATORY AS REQUIRED IAW AMM 05-51-10-200-801C. FOUND FWD AFT WATER HEATER EMITTING ODOR. INSPECTED WIRING IN ADJACENT AREA, NO DAMAGE FOUND. REMOVED TOP COVER OF WATER HEATER & CONFIRMED STRONG ODOR PRESENT. DEACTIVATE & DEFER WATER HEATER.