Does this unit function without a pressure differential

Smith and Lochinvar

The Belimo KH8 is designed to clamp onto shafts ranging from 10 mm to 18 mm (approximately 3/8" to 11/16")

Versatile Application: Optimized for air

Lennox 98M85 Ignitor R-134A Does this unit function withoutThe Lennox 98M85 Ignitor (also identified by part number 100220 01) is an OEM silicon nitride hot surface ignitor designed for high performance gas furnace applications. Engineered specifically for Lennox, Armstrong, and Ducane heating systems, this replacement furnace ignitor produces a precise, high temperature spark to ensure consistent fuel ignition and reliable startup cycles. Unlike standard glass or silicon carbide alternatives, the 98M85