Lavatory Hot
No failure report names the lavatory hot. 2 FAA approvals let 1 company make a replacement lavatory hot, Vogt Aero holding the most (2).
Approved replacement parts 2 parts manufacturer approvals
A parts manufacturer approval (PMA) lets a company other than the aircraft's maker make a lavatory hot and sell it as an approved part for the models named. These are the companies holding such approvals for a lavatory hot:
For these models most: Boeing 777 (1), Boeing 767 (1), Boeing 757 (1), Boeing 747 (1), Boeing 737 (1), Boeing 717 (1).
Sources: the FAA's service difficulty reports since 1995 (a report is a part that failed and was fixed, as filed by an airline, repair station or owner; the count shows reporting as much as reliability) and the parts manufacturer approvals in the FAA's Dynamic Regulatory System. The part name is the reporters' and the approval holders' own words, reduced to the first plain words so that spellings meet.