Install entire unit inside building

[MixManSC]

Attached image might help explain it. I'm finishing out about 5200 SF of interior space in an existing 10k sf building I have. The building is close to the property line, no easy way to install a roof top unit, no real room on other 3 sides of building for a unit. I possibly could get the neighboring owner to let me have the huge 10 ton unit stick 8 feet out onto their property but one of my guys here had the idea of cutting into the side of the building and setting the entire package unit inside the building. This would also eliminate having to build up a slab for it to site on outside that would need to raise it up about 2 feet from the existing outside ground level.

Basically would also keep the unit out of the weather and give added security to the unit since we could install a chain link gate on the outside. We would completely wall the opened space up sealing it off from the inside. Is there any code issues to doing this?

I do realize would could also go with a split system instead of a package but I already happen to have a 10 ton package unit sitting around unused. Its also a commercial 3 phase unit and I have 600 amp 3 phase (delta) power service and a fairly massive 3" gas main to the building so I'm all set on power for it.

Adding a chainlink gate to the outside will serve a few good purposes. 1 - keep anyone from trying to rip the copper out (dang thieves), 2 - keeps critters out, and 3 help to keep leaves and **** out.

 

[JCfreak]

You just need headroom above the unit. Probably should slope the roof upwards as well.

 

[porschedude996TT]

Sounds good to me, you certainly have the space to do it...

 

[fastcar1954]

unit needs airflow around and above it. 6 ft min above unit. plus a way to service it.

 

[Boyd]

You just need headroom above the unit. Probably should slope the roof upwards as well.

I second this. Instead of making the roof to the enclosure flat, make it angle up at about a 7/12 pitch (30dgs).

 

[theoldwizard1]

unit needs airflow around and above it. 6 ft min above unit. plus a way to service it.

This, plus insulate all walls and ceiling !

 

[LS6 Tommy]

I'm on board with the above statements about clearance. Look at the spec sheet for the machine to get minimum side/top clearances. It's gonna be a little noisy, too. If it has gas fired heat, it's a no-go. It has to be exposed to provide combustion air & exhaust. You definitely can't enclose it with an economizer.

Tommy

 

[MixManSC]

Thanks for the replies. Been quite some time since I looked at the unit. Went and checked it over and refreshed myself on it's specs. Ideally I'll want the condenser toward the outside which means I'll have the ductwork coming out of the opposite end I'd prefer but not a big deal. Carrier calls for 4' clearance on all sides (except for the duct end when side ducted). So realistically I'll have the duct end pretty close to the wall, while the back, other end, and top will get at least 4 foot clearance. I like the suggestion of more on top with a slight angle for the ceiling and I will have gobs of unused space above so I'll taper the ceiling from 4' at the inside to about 5' at the outside.

The unit is a big ol' hoss. 60" wide x 90" long x 50" tall. Oddly with this property I have more free interior space than outside space. 1.25ac with 21500sf of buildings leaves little for parking and movement.... I was also thinking on sloping the floor to the outside - maybe an inch higher at the innermost end. Not sure of the best way to accomplish that - looks will not really matter. The current floor is a 10" slab so I'm thinking of just pouring a little concrete on top?? The plan will be to frame in inner walls as 2x6 to allow for heavier insulation and soundproofing. I need to figure out what will be best for that. I'll cover the inside facing into the main building with osb and the side facing the unit with something I can make 100% waterproof.

I had forgotten but the unit is fully electric including the heat and it does not have an economizer installed.

 

[LS6 Tommy]

Sounds like you're pretty good to go. I'd also suggest mounting it on vibration isolators even if it's on a slab...

Tommy