Replacement is required when the pressure drop reaches 10 psi or annually to maintain system efficiency and protect downstream equipment

The Cleveland Controls AFS-305 is a high-performance differential pressure switch engineered for precise monitoring of air flow and pressure in commercial HVACR systems

Using a longer or shorter probe than the original specification can lead to delayed responses or premature tripping

When troubleshooting HVAC control circuit power

Field Controls 46198901 Control Els PW 17895 Replacement is required when theThe Field Controls 46198901, specifically the Model 4" MG1, is a professional grade double acting barometric draft control designed for precise combustion stability in gas fired furnaces and boilers. Engineered for high efficiency venting systems, this 4 inch regulator stabilizes erratic automotive drafts caused by fluctuating outdoor temperatures and wind velocities. By maintaining a constant negative pressure between . 01" and . 1" water column