Coleman-Mach 45000 heat pump model and temperature-split prep

Use this when a Coleman-Mach 45000 heat pump owner needs model, serial, ambient, return-air, and supply-air notes before HVAC service.

Owner-safe checklist

• Record model number, serial number, thermostat setting, fan speed, mode, outside temperature, and inside temperature.
• Measure only normal return-air and supply-register temperatures if the RV is safe and the unit is operating normally.
• Photograph owner-visible labels, thermostat state, filter condition, and the symptom timing.
• Use qualified RV HVAC service for no cooling, no heat, high-pressure lockout, abnormal noise, repeated shutdown, or service beyond normal filter and control checks.

Official sources

• Coleman-Mach 45000 Series Heat Pump Owner Manual 1980-054