and 3ARR3MARS65 units often found in high-performance HVACR systems

Total Internal Restoration: Includes a high-durability diaphragm

Plenum Rated: Built with a 1/2" NPT nipple and UL listed for use in plenum spaces

and 60-24180-01

Always verify the part number cross-reference before installation

Carrier HH22QC074 Thermostat 30067439-890 and 3ARR3MARS65 units often foundThe Carrier HH22QC074 Thermostat is a high precision OEM control component engineered for light commercial and residential HVAC applications. As the direct replacement for HH22UC034, this unit ensures seamless integration with existing system wiring and mounting configurations. Designed primarily as a PTAC thermostat, it provides reliable 24VAC regulation for heating and cooling stages, maintaining tight temperature tolerances to optimize mechanical