Daikin question

[Lsuby2]

New Member here! I plan on upgrading my 15 year old, 5 ton central air system, with a new 5 ton Daikin DX20VC. Along with upgrading the a/c system, I'll be adding a cathedral ceiling in the main room that will add approximately another 500 sq ft. Is it possible to have a 4 ton coil for the front of the house, approximately 2300 sq ft, and a 2 ton coil for the bedroom side of the house, approximately 1000 sq ft? I had a Daikin commercial rep tell me this was possible with the DX20VC unit as long as the air handlers and coils also were variable speed. Anyone familiar with this setup? Thank you in advance

[rider77]

You need to start with a proper load calculation to determine proper system size.

[pecmsg]

Sounds like your guessing at the size?
Try getting a manual “J” and sizing it properly.

[BaldLoonie]

Somehow I can't imagine Daikin approving of such a thing, even if it can be wired and work right.

[hvacvegas]

So your blowers are going to constantly run, and blow cold air in the addition space even when it's not needed?

I think that your Daikin rep has no idea what he's talking about, or doesn't understand what you want, or the consequences of what your trying to do.

No. It won't work. Even if it technically functions, you won't be comfortable.

Even if your doing 1 furnace, 2 coils, that still wouldn't make sense. Just use 1 coil

[Mr Bill]

What? I think there must be some sort of misunderstanding here.

[dan sw fl]

New Member here! I plan on upgrading my 15 year old, 5 ton central air system, with a new 5 ton Daikin DX20VC. Along with upgrading the a/c system, I'll be adding a cathedral ceiling in the main room that will add approximately another 500 sq ft. Is it possible to have a 4 ton coil for the front of the house, approximately 2300 sq ft, and a 2 ton coil for the bedroom side of the house, approximately 1000 sq ft? I had a Daikin commercial rep tell me this was possible with the DX20VC unit as long as the air handlers and coils also were variable speed. Anyone familiar with this setup? Thank you in advance

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