If the switch is open while the furnace is cool

this 40-004-A4 rubber repair kit provides all necessary elastomeric components to restore performance

or a complete failure of the system to initiate the cooling or heating sequence despite receiving a 24V signal

Where should the KVP be installed

Nordyne 669578R TXV 320788-702 If the switch is openThe Nordyne 669578R is a high performance 5 Ton R410A TXV designed to provide precise refrigerant metering for residential and light commercial air conditioning systems. Engineered for N Series evaporator coils, this TR6 Thermal Expansion Valve maintains optimal superheat across varying load conditions, preventing compressor liquid slugging while maximizing evaporator coil efficiency. As an OEM Nordyne replacement part, it ensures seamless