Check the part number stamped on the existing orifice or cross-reference the Reznor replacement parts catalog using your unit’s model and serial number to ensure bore size alignment

The manual reset (M/R) configuration requires a technician to physically inspect the system for airflow obstructions or combustion issues before restoring operation

ensuring the correct BTU output and preventing soot accumulation or delayed ignition caused by improper fuel-to-air ratios

5 screw terminals are designed to accommodate up to 2 x 2

Carrier HH18HA490 Rollout Switch Check the part number stampedThe Carrier HH18HA490 Rollout Switch is a critical safety component designed for high efficiency gas furnaces. This manual reset rollout switch is engineered to monitor temperatures within the burner compartment, providing essential protection against flame rollout conditions. Functioning as a Single Pole Single Throw (SPST) device, it is calibrated to open the electrical circuit at approximately 290 degrees F, effectively shutting down the system if