Lennox 78H40 Expansion Valve Refrigerant If you're seeing oil seepage

If you're seeing oil seepage on the shaft or getting a "limit trip" due to low airflow

It monitors pressure thresholds rather than temperature probe activation

managing the 3nd-stage spark and flame sensing for reliable start-ups

Can this handle chilled water applications

Always verify the rating plate on the appliance before installation

Lennox 78H40 Expansion Valve Refrigerant If you're seeing oil seepageThe Lennox 78H40 Expansion Valve is a critical 6 ton thermostatic expansion valve (TXV) engineered for precise refrigerant metering in high capacity light commercial and residential cooling systems. As a veteran grade HVAC replacement part, the 78H40 (identical to Lennox 78H4001) regulates refrigerant flow into the evaporator coil by sensing heat load changes, preventing liquid slugging and ensuring the compressor receives superheated vapor. This TXV