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Bigdog
Significance of Suction Line Size on OD AC unit

Could someone tell me the significance of the coolant line size running to the indoor coil. I was told that my 5 ton outside unit SHOULD be run with at least 7/8" to 1 & 1/8" size line to the coil and it's not. You can see where they sized it down to 3/4 when it was installed. The run length is only probly 8 to 10 feet however and maybe this is why BUT I would still like to know what effect the smaller line would have. I've been thinking of upgrading my outside unit with a newer higher seer rated unit and wonder if this will have to be changed to at least 7/8" for a 5 ton 15 seer rated unit. Thanks

Bob Gabrilson
Re: Significance of Suction Line Size on OD AC unit
Bigdog wrote:

Could someone tell me the significance of the coolant line size running to the indoor coil. I was told that my 5 ton outside unit SHOULD be run with at least 7/8" to 1 & 1/8" size line to the coil and it's not. You can see where they sized it down to 3/4 when it was installed. The run length is only probly 8 to 10 feet however and maybe this is why BUT I would still like to know what effect the smaller line would have. I've been thinking of upgrading my outside unit with a newer higher seer rated unit and wonder if this will have to be changed to at least 7/8" for a 5 ton 15 seer rated unit. Thanks

Too small of refrigerant lines will effect the efficiency and the capacity.
When the new system is installed, I'm hopeful they'll install the right size lines.

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