The Aprilaire #51 current sensing relay simplifies air cleaner installation on furnaces without accessory terminals.

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Product Review

The Aprilaire #51 current sensing relay simplifies air cleaner installation on furnaces without accessory terminals.

  • Voltage Range: 100-125 VAC, 50-60 Hz
  • Sensing Current: Minimum of 4.0 Amps
  • It can also be used to simplify installation of inline duct booster fans
  • Relay must sense all four amps in order for it to open and close properly