J asked in Home & GardenMaintenance & Repairs · 3 weeks ago

Static pressure on an air handler.?

When we use static pressure probes to test air flow inside a furnace, we put one probe before the blower, and the other probe before the cooling coil.

This means that the cooling coil is not included.

But if we measure a central unit that only has a cooling coil, we put the pressure probes before the blower and then after the coil, which means that the coil is included.

How does this make sense.

1 Answer

  • 3 weeks ago
    Favorite Answer

    It doesn't since the flow rate at the fan's outlet has to be the same as the flow rate downstream of the cooling coil or any other device that is in the flow stream. The main advantage of having the downstream probe after the coil is the reduction in turbulence that you will get downstream of the fan.

    • J3 weeks agoReport

      So why would the furnace measurement include the heat exchanger?

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