the 3/8" x 4" bulb can be used for liquid sensing

this module is the authorized OEM replacement for the Robertshaw RAM-2MC17-02 model used in many Aaon legacy units

Direct Replacement Logic: Engineered as a high-reliability successor to 4074BYK and 4074EED (Mod IV version)

Broad ICP Compatibility: Direct OEM fit for a wide range of Heil

For technicians servicing York E1RD series units

Nordyne 903477 Heat Exchanger THPU32HP7Y the 3/8" x 4" bulbThe Nordyne 903477 Stainless Steel Heat Exchanger Assembly is a high performance, factory authorized OEM furnace replacement part engineered for technical reliability in Nordyne R4 series gas packaged units. This 4 tube heat exchanger is manufactured with premium grade stainless steel to address common failure points like stress cracking and corrosion caused by condensation and high thermal cycles. Measuring 30 inches in length, the 903477 assembly