Hi Guys
I want to buy an AC 2 ton but I have a fairly large air plenum on my furnace about 20 by 22 inches and any AC’s that I have looked at come with a smaller A Coil so if I used this it would greatly reduce my air flow. The A Coil looks like it is meant for a furnace in an apartment size furnace. Do manufactures just make the one size now? Is there any where I can get a larger A Coil or even a Slant Coil that might be of a larger size?
Thanks
Rick

The coil boxes come in different sizes. A two ton coil will measure around 14 inches wide and 18 or so from front to back. You can make and transition to fit your plenum or you can have on made.
You should determine how big of an AC you need and not just decide that you want a two ton.

Thanks for responding
That is exactly the size of the A coil and that is the size that comes with 1&1\2 ton as well. I can make the transition no problem but If I’m going to restrict the flow of air down from 20 by 22 to less than about 15 by 11 because your dimensions are the out side of the coil then why do manufacture’s of furnaces make there opening so big. Going from 20 by 22 to 15 by 11 this is a big difference. There must be an A coil out there that is closer to the size of my opening on the furnace
Rick

Quote:

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Originally Posted by trickyrick0465

Thanks for responding
That is exactly the size of the A coil and that is the size that comes with 1&1\2 ton as well. I can make the transition no problem but If I’m going to restrict the flow of air down from 20 by 22 to less than about 15 by 11 because your dimensions are the out side of the coil then why do manufacture’s of furnaces make there opening so big. Going from 20 by 22 to 15 by 11 this is a big difference. There must be an A coil out there that is closer to the size of my opening on the furnace
Rick

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The coil is sized to allow the right amount of air to pass through.

Look at your blower assembly to determine the minimum sized opening typically 10" x 10"

Ok I know that the blower is about 10 inches by 10 inches. But what Im thinking is that if I were to install a plenum 10 by 10 then I would not get as much air flow as if I were to install a plenum 20 by 20. I know that the A Coil is sized for the AC unit, I just can't get my head around that fact that it will restrict my air flow dramaticly. Would it not make sense to insert an A Coil that was a bigger size letting more air through
Thanks
Rick

Quote:

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Originally Posted by trickyrick0465

OK I know that the blower is about 10 inches by 10 inches. But what I'm thinking is that if I were to install a plenum 10 by 10 then I would not get as much air flow as if I were to install a plenum 20 by 20. I know that the A Coil is sized for the AC unit, I just can't get my head around that fact that it will restrict my air flow dramatical. Would it not make sense to insert an A Coil that was a bigger size letting more air through
Thanks
Rick

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Actually the air needs time for exposure to the coil to give up its latent heat.
If the air moves through too quickly you won't get the temperature difference needed to operate properly.

I know it sounds screwy , but one solution would be to oversize the indoor coil by say 1/2 a ton to get better De-humidification,I've done this on my own home, IE; 2-1/2 ton condencer w/ 3 ton evaporator coil.

This would give you a coil with an additional need for more air movement, a larger opening and , satisfy your need to have a coil fit the existing plenhum.

Thanks
That sounds reasonable I think I will do that
Thanks again for everyone's input
Rick

I would agree and have done this also. Oversizing the coil is an old practice that works. Not that the smaller coil wouldn't, but I believe in oversizing the coil a bit to allow better cooling and less load on the system overall due to increased capacity...

Does anyone know a web sit that has the different size coils with dimensions
I would like to know the difference between a 2 1\2 ton and a 3 ton coil
Thanks