It should not be confused with a vent limiting device (vLimiter) which is installed in the vent connection to manage diaphragm relief

Adjusting gas components like the Lennox main burner involves verifying manifold pressure and ensuring there are no gas leaks

While primarily a York/Johnson Controls part

System Reliability: Protects capillary tubes and expansion valves from organic acids and oil decomposition products

the 3T series provides a specialized geometry compatible with Series 3G and other custom industrial configurations

Zonefirst ZDB-12X18 12HX18W Parallel 24V 2-Pos S/R THPU32HP7Y It should not be confusedThe Zonefirst ZDB 12X18 is a professional grade 12HX18W Parallel 24V 2 Pos S R zone damper engineered for high static HVAC environments. Built with a heavy duty extruded aluminum frame and 3 inch parallel blades, this bottom mount zone damper ensures quiet, low leakage performance in rectangular ductwork. The unit utilizes a 2 wire spring return motor rated for 24VAC, providing a fail safe open position when de energized and a powered closed state.