Universal Defrost Controls w/ Jim Fultz

In this podcast episode, Jim Fultz with White-Rodgers joins us to discuss universal defrost controls. He also explains when and why you might use universal controls. Bryan and Jim cover a universal defrost control for heat pumps (Model #: 47D01U-843). You can follow along by reading the manual HERE.

Universal defrost controls can replace OEM defrost controls. Universal controls are sometimes more readily available than OEM parts, so they can be good repair options.  The White-Rodgers universal heat pump defrost control comes with the board, installation instructions, two wiring harnesses, two thermistor-style sensors, and a bag with screws, wire nuts, and other mounting materials. This particular control is compatible with 400 different product SKU numbers, so it's a versatile replacement.

The display of the White-Rodgers universal heat pump defrost control gives a lot of feedback; it has orientation options and can communicate more information than mere flashing LEDs. You'll have to set the display orientation in an ideal position, but the controls will help you out with that.

You'll also want to keep these defrost controls out of the sun, away from snow, and on the back of the unit. If you don't already have an outdoor coil temperature sensor set up, then you'll want to install the sensor at the bottom of the condensing unit coil.

As far as the actual defrost options go, you can set seven different options that correspond to specific manufacturers' controls (OEM Quick Setup). The short cycle time, reversing valve, time delay, and maximum defrost times can be tailored to each manufacturer's equipment.

Jim and Bryan also discuss:

  • Spade connections
  • Wiring diagrams for the universal defrost control
  • Outdoor thermostat and electric heat
  • Oil behavior
  • Demand defrost
  • Annual energy savings
  • Table settings
  • Reversing valve shift delay time
  • Auxiliary heat
  • Low-temperature compressor cutout
  • Brownout protection
  • Force-initiation

Learn more about Refrigeration Technologies HERE.

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