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Replaced Defrost Board - Outdoor Unit Won't Come On

Article ID: 78
Last updated: 30 Jan, 2023

York Heat Pump

Re: 331-01975-102 DEMAND DEFROST CONTROL


Issue: Outdoor Unit Won't Come On

The Demand-Defrost control has a selectable defrost curve. The original board is programmed at the factory with the correct defrost settings for the unit on which it is installed. The factory-programmed board is set on defrost curve "P".

  • Replacement defrost controls have no program, but the control comes out of the box set on "P".

What to do:

  • The jumper pin MUST be placed in a numbered position. (The most common is position "2")
  • If the jumper is missing or in the "P" position, the replacement control will not energize the compressor.
  • Use Pin Position 1 for reciprocating compressors and Pin Position 2 for Scroll compressors.
    • Do not use Pin Positions 3 or 4 unless instructed to do so by Tech Support.
  • When the jumper position is changed, the control will not act upon the jumper change until the thermostat calls are de-energized or 24V power to the control is cycled.

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Article ID: 78
Last updated: 30 Jan, 2023
Revision: 9
Access: Public
Views: 199
Comments: 0
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