Pentair Air Flow Switch For MasterTemp And Max-E-Therm Heaters | 42001-0061S Pentair 4000 Series Tank O Ring helping to prevent clogs and

helping to prevent clogs and mechanical damage

helping to maintain excellent functionality

Needs to be replaced: Every 3-4 years or when 0

With 60 sq

Pentair Air Flow Switch For MasterTemp And Max-E-Therm Heaters | 42001-0061S Pentair 4000 Series Tank O Ring helping to prevent clogs andThe OEM Pentair air flow switch (AFS), which senses the pressure drop across the air metering orifice. The air flow switch (AFS) senses the pressure drop across the air metering orifice. As soon as there is sufficient air flow, the AFS closes, closing the circuit to the hot surface igniter (HSI), which ignites the fuel mixture. On a call for heat, the blower and HSI are energized. In about 20 seconds, the gas valve opens and ignition occurs. The HSI