[Trocque]

Greetings HVAC-Talk friends!

I'm working in Chicago and have been tasked with sizing the proper system for a three 10,943 lbs capacity elevators. The elevator equipment room is approx. 800 sq ft in size, with brick walls, and it is on the 18th floor.
How do I determine the size and type of unit to install?
The customer wants to have a 42,000 Btu split heat pump system installed (he wants supplemental heat in the frigid winters). I told my boss that I didn't think a heat pump in Chicago winters (weeks on end it can get well below 0 degrees) was a good choice. Also, the customer does not want the outdoor condenser to sit on the roof, it must be mounted on the side of the elevator room outside wall. This means that he has a residential split system in mind. Is this possible? Is this a good decision?
So, if someone could tell me how to take a proper load count on an elevator room (i.e. does one need to take the HP of the motors into consideration) and what the most prudent system configeration would be, I'd be verygrateful.

 

[craig1]

I did this exact job, but 4 elevators, also in chicago. I used two 3 ton residential condensers and air handlers. I sized it based on the fact that this was the largest unit that could be carried through the building. Anything larger would require a helicopter lift.

I told them if that wasn't enough, we could add additional 3 ton systems. It worked fine with just 2 and the room was all windows.

 

[Trocque]

Thanks Craig!

I thought about using residential units, but he also wants supplemental heat with no gas going up to the 18th floor. Then I wondered about having to apply duct work to the coil. Then I thought about installing a mini-split, but then I would be stuck with having to install electric heaters. What I ended up doing is calling my buddy at W.L. Engler and he turned me onto a Bard W36A1 wall mounted packaged air conditioning unit with a low ambient kit and a 15 kw heater. I think in this application and considering the budget I think this would be the best option. However, after I do another walk through I might find that this is not a good option, at which time I will have to review the residential units again. One of the really nice things about this job, and I found this out after I made my previous post, was that the total Btu output per day is only 45,000. I did a load calc. on HP assuming that the elevators were not efficient and came up with a number that would be equal to 12 tons of cooling. Ouch!
Again...thanks for your rely