Commercial Building HVAC Identification and Info

Hi, I am soon going to inspect a large commercial building. I am only inspecting several of the suites and am concerned about my ability to offer my clients a thorough understanding about the HVAC sytem. The sytem has 2 boilers in the basement and a chilling tower on the on the roof. I am asking anyone what the exact proper terminoligy for this type of heating and cooling system. I want to understand more about it than I currently know. I have my own opinion, but in this case I need to be exactly right.


Without going into any detail regarding what you should be writing in the report, I can tell by the question you need to sub this out to a licensed contractor, have him give you his report, and add it to the property condition report.


Plus…you will learn a great deal by having someone familar with these type of heating & cooling systems which will come in handy for the next inspection.

When there is a cooling tower involved don’t even write a single thing about the equipment unless you have a qualified contractor with you to do so correctly.

Uh-huh. Can you say Legionaires? :frowning:

I agree completely, and I am not going to inspect the chilling tower or the bolier. What I was looking at are the individual air handlers in the individual suites. There are 6 or 8 of them and I understand they are part of a bigger sytem. What are these called…Air Handlers, blowers…

Any of the above. In commercial, we’d typically call these a fan coil unit, wether or not it’s mounted below the window, or above he ceiling with connected ductwork. It might even be a VAV box, but I sorta doubt it if you have both chilled water and boiler water. If you have a big RTU for the A/C and a boiler water coil, it’s probably a VAV box. Since you have both chilled water and boiler water, just call it a fan coil unit and you’ll be good. They’re pretty simple, in reality. Just two big radiators and a blower. Probably a zone valve or a 3-way valve to turn the flow on or off. Some of these only have one coil, and the building management makes a decision at some point in the season whether to deliver chilled water or heated water through the system. This arrangement sucks, but is popular in older buildings that only originally had heat.

It is exactly as you describe, I think the building management determines when they have cold or hot air. They are mounted in the ceiling of these office suites. There are several thermostats in each suite, but the maintnence guy said he now controled everything from one central location. It is a very old building that has been renovated many times. I estimate there age at around 20 -25 years old. My client who currently resides in another section stated they were concerned because of the number of times thay have had to call on repairs for there current office space. I am not making any claims to have inspected the entire heating system, just want to give them some info regarding these paticular items. The set up is alot like a HOA at a condo. The tenants really do not have any say in the system performance or reliablity, but they want to know if they at least work.

Sounds like you’ve got it easy, then. Seems like all they want you to do is cut the bitch on and see if it makes warm air (or cold air)?

Ya, I think I do. Everything is owned by the owners, it is a lease and I guess they had some problems before in California. There original inspector finked out on them at the last minute and it fell in my lap, but absolutely no lead time. It is a great oppurtunity. Thanks for your help.


If you’re near Boulder on Tuesday, come to the chapter meeting. I may have some general info I can share as to common configurations and terminology.

Marc has given you some sound advice.

Dale gave you the best advice.

You’ll probabiy only be able to check it in the mode it set to at the time of inspection. Some can take quite awhile to switch back over to the other mode. But if there is a maintenance man or building eng. He might be able to help you out.