RLF Series

Thermo King RLF Series Bus HVAC unit.

RLF Series

Rooftop HVAC System for Coach and Transit

Integrated rooftop bus HVAC system for coach and transit applications. Replaces existing roof-mount units with a unit that weighs 42% less and replaces rear-mount units without sacrificing reliability, performance, weight or cost.

RLF Series bus coach HVAC front view.

Standard Features

IntelligAIRE III® Control System

  • Expanded CAN communications capability
  • Plugs directly into J1939 network to make more info available
  • Eliminates the gateway module required between bus & unit controllers
  • Less weight due to elimination of harnesses
  • Increased number of I/O for system & component monitoring 
  • Eliminates need for expansion modules external to controller where multiple zones must be controlled independently
  • Programmable pre-heater function with real time clock activation to start pre-heat when system is off

Optional Features

S391/S616 Screw Compressors

  • Exclusive oil management system for increased reliability
  • Fewer moving parts than reciprocating compressors
  • Lower noise levels and vibration than reciprocating compressors
  • Programmable capacity control for fuel savings

Electronic Energy Management System

  • Provides fuel savings with X426, X430, and X640 reciprocating compressors
  • Programmable electronic capacity control reduces the parasitic load on the engine

Benefits of the RLF Series


HFC Refrigerant R-134a or R-407C

  • Environmentally safe alternative providing protection for the earth’s ozone layer

The Thermo King X430 Compressor 

  • Engineered exclusively for transport applications
  • Built for extended service life
  • Field repairable

Next Generation Brushless Motors 

  • Integral electronics
  • No external controllers
  • Maintenance free
  • Advanced diagnostics
TE-Series bus HVAC units are part of our all-electric portfolio

Committed to sustainability

RLFE Series electric bus HVAC units are part of our all-electric portfolio, called evolve™. The evolve portfolio aligns with our customers’ goals to transition to more sustainable solutions for their fleets, and will help advance Trane Technologies’ 2030 Sustainability Commitments, including its Gigaton Challenge to reduce customer greenhouse gas emissions by 1 billion metric tons.



Support wherever you need us

With the Thermo King Dealer Network, you have access to service and proactive maintenance at over 200 locations. Find the support that’s closest to you with the online dealer locator—complete with contact details and service offerings.

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