Where does this harness connect in the furnace

Field Serviceable: Features replaceable components and an inlet screen to protect the internal seat from line debris

it can be installed in return air ducts provided the 18 3/4-inch sensing element is adequately exposed to the main airstream for accurate sampling

While technical specifications might overlap

Reversing rotation will significantly degrade airflow and may lead to compressor overheating

Beckett Igniter 51621U Unit Heater 323080-701 Where does this harness connectThe Beckett 51621U Igniter Unit Heater Start Helper Kit is a critical accessory for oil fired systems where cold starts often lead to poor combustion or delayed ignition. This genuine Beckett Start Helper utilizes a solid state, self regulating heating element to maintain consistent oil temperature within the nozzle line. By pre heating the fuel, the 51621U ensures superior oil atomization, resulting in smoother light offs and higher combustion