Centralite Pearl Thermostat - won’t turn off A/C

I recently purchased a Centralite Pearl thermostat for my A/C unit. Just A/C-/ not a heat pump.

When connected to the thermostat, the A/C unit never shuts off.

The HVAC guy said it is sending a request for cooling on Y even though the set point is reached and even if the thermostat mode is OFF.

We double and tripled checked the wiring and the settings (set to Cool Only).

Is there something I’m missing? Maybe a setting that could cause this?

I sent an email to support@centralite.com but would welcome any assistance here!


So usually, these are issues with wiring. Could you post photos of the wiring at the thermostat AND at the air-handler/furnace control board?

Did you perhaps take a photo of the old thermostat wiring? It might help with troubleshooting.

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Since the Pearl thermostat didn't work as expected, I have another non-communicating thermostat installed and it works correctly so I'm reasonably assured that the wiring is correct. The photo I've attached is of the currently installed thermostat but the wiring for the Pearl was to the same terminals.

I do have a photo of the old/previous thermostat wiring but it was connected to a heat pump. I got rid of the heat pump and instead installed an A/C only unit.

I was hoping that there might be a setting in the thermostat menu that is causing this behavior. Does anyone have a Pearl Thermostat connected to an A/C only unit that could share their thermostat menu settings? THANKS FOR ALL OF THE HELP!

I have 2 pearls but heating only sorry... maybe remove the jumper between RH & RC? - not sure why this would matter though. Otherwise the wiring looks good to me.

I had a pearl for heating only however I don't see why cooling only should be so difficult.

I can't see any settings that would keep the A/C on above the setpoint.

Question: Is the A/C compressor on and the circulation fan or just the circulation fan only.

If you go to menu 18 the display will list all the settings. I would take a video of the screen as they go by and sort out the settings later.

When the Pearl is in place both the air handler fan and the compressor fan are on.

Again, the compressor and fan internal relays should both go off when the targeted temperature is reached.

Could be a bad thermostat, ebay or retail?

I would:

  1. Reset the thermostat by by going to menu item 17
  2. if still bad I would take the batteries our, remove all the current thermostat wires and see if "G" in connected to "C" (it should not be)
  3. Do the same for "Y1" and "C"
  4. It shouldn't matter but I would try removing the "RC" to "RH" jumper.
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Since I have a second Pearl thermostat I swapped them and the second one works just fine with the A/C. I guess the first one is bad. I bought both brand new from Amazon. (I need the other one for my heat only so if it works for heat then I’m good to go.). THANKS EVERYONE FOR THE HELP.