What size AC?

[HotShoe]

I just found out the existing AC compressor in my warehouse is toast so I have to look at a new system.

I have a 20' wide x 50' long x 16' high open rectangle. CBS construction and concrete roof, northern exposure with an insulated 12' roll up. I'm doing an open floor plan with a loft so I wasn't considering any ducting to keep things simple. 150 amp service.

What size unit would be ideal for those dimensions? The warehouse is located in south Florida.

 

[HotShoe]

I was told today 3.5 to 4 ton by the first tech. No price yet.

 

[HotShoe]

The 20' side faces north.

I asked the same question about ducting but they suggested to simply mount the handler on the 50' wall on a stand and then run a plenum straight up with a duct blowing out the front and each side.

 

[hdossett]

Size does matter! Better to go smaller and more efficient, than larger and less efficient! Units too large will cool down fast but will not dehumidify, and that is very much needed in S. FL.

In the end, if a unit runs constantly and maintains temps, on the hottest day of year, it is just right!


H

 

[HVAC Phil]

The 20' side faces north.

I asked the same question about ducting but they suggested to simply mount the handler on the 50' wall on a stand and then run a plenum straight up with a duct blowing out the front and each side.

Was this an actual HVAC contractor recommending this or a wanna be HVAC guy because he has a set of gauges and an online EPA lic? Must not know how to size duct work correctly...let it blow wild! YEE-HAW!

 

[HotShoe]

Was this an actual HVAC contractor recommending this or a wanna be HVAC guy because he has a set of gauges and an online EPA lic? Must not know how to size duct work correctly...let it blow wild! YEE-HAW!

It was a very big AC company that's been around a long time.

I'm very cautious down here with AC companies. I get the impression they just want to cookie cutter every job and turn a quick profit. I'm not looking to go cheap but I don't want to just throw money around. I want best bang for the buck. If I owned the building I would just go full bore.

Maybe I'm just not the trusting type but I'm getting at least three est. from legit companies. We'll see what the second guy says this week.

 

[klhitman]

was your old unit ducted?

 

[HotShoe]

That doesn't mean anything.

I know. I was answering HVAC Phil's question about wether it it was a company or shade-tree.

If you rent/lease, I would invest no more than what is comparable to the agreement. If it is put in right, you could expect 15 years from the equipment, barring unusual circumstances. If you don't have half of that time ******* in a lease, I'd band-aid it together.

That's the problem. I can't get more than a years agreement so anything I invest is a calculated gamble. I'd like to fix what's there but as I said above I don't think I've found anyone that wants to bother. I don't mind paying for a good solution I just want to make sure I have a little info so I don't get taken. AC companies in south Florida in the summer can be picky if they want to.

was your old unit ducted?

The old unit had a half-*** duct that came off the handler straight up and then t-ed out two feet on each side with for a total of three vents. It was done almost as poorly as the electrical I tore out!