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Hey folks.

So what is the difference between a slab coil for low velocity and high velocity? Assuming TXV is in, is the difference only in dimensions? High velocity is wider, while low velocity is taller and deeper?

What happens if high velocity coil used with a low velocity air handler?  The supply duct is greater ofcourse, but I guess it gets choked in the coil and there is not enough velocity?

Usually on a high velocity air handler you would install the coil on the return side.  I've seen the more expensive slab coils used and standard A-coils used and never came across a static problem issue with either. 

The Air Max high velocity air handler has a round duct port and that's why I mention installing the coil on the return side.

It is good practice to install a tee in your drain line with these types of systems as they tend to pull the water back into the air handler.

Yeaaah.  The issue isnt about placing a low velocity coil on a high velocity air handler.

The issue is placing a slab coil rated for high velocity, on a low velocity air handler.

I have the room for giant ducts. Its a 4 ton unit and the air handler can push 2.4k cfm, but I wonder if the slab coil dimensions will choke down the cfm and without the velocity - freeze up.