this device is specifically engineered and tested for UL555(S) fire and smoke applications and should not be used as a safety limit in other non-rated systems

making it a versatile HVAC control board replacement for service vans

The separate O and B terminals provide maximum flexibility for heat pump reversing valve configurations

While the 24V coil can accept DC

Carlyle HT31AZ120 Crankcase Heater Freon this device is specifically engineeredThe Carlyle HT31AZ120 Crankcase Heater is a critical component for maintaining compressor reliability in low ambient conditions. As an insertion type heater, it provides direct thermal transfer to the lubricant, effectively preventing refrigerant migration and ensuring a flooded start does not occur after extended off cycles. Rated at 120 Volts and 100 Watts, this heater is engineered for high performance thermal regulation in Carlyle semi hermetic