Trane M5MHWUN18A1N0A Ductless Mini-split Air Handler 18000 Btu/h 19 Seer R-454B 208-230V

Product Description

The Trane M5MHWUN18A1N0A is an 18,000 BTU/h ductless mini-split indoor air handler designed for single-zone cooling applications. Part of the Runtru 19 Series, this unit operates on R-454B refrigerant, a lower global-warming-potential alternative to R-410A, making it suitable for installations where updated refrigerant compliance is required. Rated at 19 SEER efficiency and configured for 208-230V single-phase power, it pairs with a compatible outdoor condensing unit to deliver zone-specific climate control. Licensed HVAC technicians handle installation and commissioning of this equipment.

This air handler is intended for residential and light-commercial ductless split-system installations where a single indoor zone requires dedicated, high-efficiency cooling. The wall-mount design allows direct room-level air delivery without ductwork, making it well suited for additions, server rooms, garages, or any space where extending existing duct systems is impractical. The R-454B refrigerant charge means the system must be handled by EPA Section 608 certified technicians using equipment rated for A2L refrigerants.

Key Features

• 18,000 BTU/h cooling capacity for single-zone applications
• 19 SEER efficiency rating in the Runtru 19 Series lineup
• R-454B refrigerant — lower GWP alternative to R-410A, A2L classified
• 208-230V single-phase operation for standard residential electrical service
• Ductless indoor air handler design eliminates the need for supply and return ductwork

Compatibility

Designed as an OEM indoor air handler for use in Trane Runtru 19 Series single-zone ductless split systems. Pair with a compatible Trane outdoor condensing unit rated for R-454B refrigerant. Confirm matching capacity and voltage ratings before ordering.

Installation Notes

Installation must be performed by an EPA Section 608 certified HVAC technician experienced with A2L refrigerant handling procedures, as R-454B has a mild flammability classification requiring specific tool and safety protocols. Shut off all electrical power to the circuit before mounting the indoor unit or making any wiring connections. Follow local mechanical and electrical codes, including NEC requirements for disconnect placement and wire sizing at the rated voltage and amperage. Do not mix refrigerant types or use recovery equipment not rated for A2L refrigerants.

Technical Specifications

• Cooling Capacity: 18,000 BTU/h
• SEER Rating: 19 SEER
• Refrigerant Type: R-454B
• Voltage: 208-230V
• Phase: 1-Phase
• Series: Runtru 19 Series
• Shipping Height: 15.95 inches
• Shipping Length/Depth: 45.87 inches
• System Type: Ductless Mini-Split Indoor Air Handler

Standard Information

• Brand: Trane
• Manufacturer Part Number: M5MHWUN18A1N0A