The MTZ series specifically requires 175PZ polyester oil (POE)

featuring a keyed plug for error-free wiring

as it prevents the "gulping" of air and provides a more linear airflow response compared to standard single-blade units

This specific unit is factory-set with a 26K Ohm sensitivity

Trane VAL9228 TXV 321702-401 The MTZ series specifically requiresThe Trane VAL9228 (also identified as VAL09228) is an OEM 3 ton R410A thermostatic expansion valve engineered for precise refrigerant metering in high efficiency cooling systems. This HVAC expansion valve features 5 8 inch mechanical fittings, eliminating the need for brazing at the valve body and reducing the risk of internal seat damage from overheating during installation. Designed specifically for Trane 3 ton evaporator coils, the VAL9228 utilizes