Mack Trucks never produced HVAC systems. Evans (vendor 2790) produced the 3-speed R/U/DM heaters. Kysor of Byron (vendor 7979) produced an integral R/U/DM heater/air conditioner (Mini Brute) that was uniquely used in glider kit production, and was also available thru Mack dealers as a retrofit kit. Introduced in the early 1980s, Signet (vendor 3230) was the first integral heater/air conditioner for the R/U/DM. Red Dot (vendor 4379) later became the integral heater/air conditioner for the R/U/DM with a superior performing design. A Red Dot HVAC system also replaced the Signet unit in late model MH production. Red Dot was again chosen to supply HVAC for the CH/CL.
