I have read the poster here:

Controlling 110v swamp cooler using Nest thermostat

about how to control the swamp cooler using the nest. However, I don't have reputation to post comments to that post yet. So I am asking a new question.

Currently, I have the Masterstat:


The model can also buy from amazon:


It has a big box with the Mastercool swamp cooler and then three lines coming out from the control board to the wall mounted control unit:

1: Fan Lo - Red wire 2: Pump - Black wire 3: Fan Hi - Black wire

I am wondering whether the 1 and 3 can connect to the Y1 or Y2 but not sure how to connect the pump.


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