Change blower speed on furnace for cooling season


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Old 06-15-24, 12:54 PM
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Change blower speed on furnace for cooling season









uxaire Unitary Model G8C10016MUC12H - 100k input/80k output
A-Coil - MC36C2AH1A Serial# A0L6074298 (3 tons)

guys - may not be visible on the am I right that the black wire on the bottom left is going to a density that says cool and brown says heat
1. does this mean currently my cool is set to high and heat set to medium high?
2. I canít find a low switch that Iíd like to attempt for the cooling season

Thanks
 
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Old 06-15-24, 01:24 PM
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does this mean currently my cool is set to high and heat set to medium high?
Yes.... that is correct.

I see.....................
black = high = cool
blue = medium = heat
red = low = park

You can't randomly slow down the blower especially on A/C.
You run the risk of the coil freezing.

You can make a Y cable and connect blue to cool and heat.
The black and red will be not used.
 
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Old 06-15-24, 01:38 PM
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Unfortunately, I have a 3 ton a-coil which is installed in the attic and just servicing the second floor, which is only 500 ft.≤ so obviously massively oversized. It does cycle every 5 to 7 minutes and not really removing humidity in this climate zone 4
1. What is the point of the Y cable?
2. I donít see a red cable, but I do want to attempt connecting cooling to low if you can guide me. I do understand the risk of this, but I only operate the air conditioner perhaps 15 total days in the summer. So far I already connected cooling to medium-but it only seems to make a marginal difference

thx
 
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Old 06-15-24, 02:42 PM
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According to the schematic you posted.... there should be a red wire.
Go to the motor and see what colors are there.
Red will probably be too slow for A/C.
 
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Old 06-15-24, 03:02 PM
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How much is the usual CFM difference in % between high & medium and medium & low?

For additional context, I have 2 large returns connected to this unit and it breathes very well
 

Last edited by lagetk; 06-15-24 at 03:13 PM.
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Old 06-15-24, 04:22 PM
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Not sure what the speed difference is.
There is detailed info on the wiring diagram but it's too small to read.
 
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Old 06-29-24, 01:40 PM
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You have a 3 ton evaporator coil but what size is the outdoor condenser?
 
 

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