As the 3RB30 series evolved

While the AC output is not inherently polarized

Rugged Construction: Designed for an ambient temperature range of -22°F to 122°F

Professionals utilizing this Lennox 69W42 replacement part benefit from a 15A at 120VAC electrical rating and a high-durability SPDT contact configuration

As a drop-in replacement part

Heil Quaker ICP Z06G001 Switch 322027-701 As the 3RB30 series evolvedThe Heil Quaker ICP Z06G001 Block Vent Switch is a critical safety component engineered for oil fired heating appliances and high efficiency furnace systems. Designed as a Blocked Vent Shutoff Switch (BVSO), this genuine OEM part monitors the exhaust flue for restricted airflow or backdraft conditions. If the venting system becomes obstructed by debris, ice, or seasonal nests, the Z06G001 switch detects the resulting pressure or temperature change to