Legacy Support: Serves as the official AK-40613 replacement

it simplifies retrofits and new installations

It is technically identical to the Honeywell 4074ELR/U

This insert orifice type pilot burner is engineered for maximum field flexibility

Whether you are performing a new multi-stage heating setup or replacing a failed element

Lochinvar & A.O. Smith 100074281 Output Thermistor 320788-702 Legacy Support: Serves as theThe Lochinvar & A. O. Smith 100074281 Output Thermistor is a critical NTC temperature sensor engineered for precise thermal monitoring in high efficiency tankless water heaters and commercial boilers. As a genuine OEM replacement part, this thermistor (equivalent to EKK2T) provides real time resistance feedback to the control board, allowing the system to modulate gas and water valves with surgical accuracy. This ensures consistent output water