Lennox 96L77 Heat Exchanger 320735-701 while the normally closed configuration

while the normally closed configuration provides fail-safe safety by automatically halting gas flow if power is lost

Designed to monitor suction pressure with high precision

Featuring auto-voltage detection

It is designed for select R4 series models requiring a 4-tube

ensuring seamless backwards compatibility with existing SpectrAlert Advance and L-Series systems

Lennox 96L77 Heat Exchanger 320735-701 while the normally closed configurationThe Lennox 96L77 Heat Exchanger (Catalog Number 96L77, superseding LB 58087BT) is a critical OEM replacement part engineered for high efficiency gas furnaces. This 125SS Heat Exchanger assembly is constructed from stainless steel to withstand high combustion temperatures and prevent premature thermal stress fracturing. Designed for large scale residential and light commercial Lennox units, it arrives as a robust assembly with a gross weight of 151