What is the best way to inspect those commercial units on the roofs that are both Heat and A/C in one? I have an inspection coming up that has this type of system and have never inspected one before.
Thanks for your help.
Thank You
Sid 
I haven’t found anything specific to look for. It’s just a packaged system incorporating both parts of a standard split system. However, perhaps I haven’t found anything specific to look for because I don’t climb up on roofs. I operate the heating and cooling system as a normal homeowner would do on a normal day, i.e., using normal user controls like a thermostat. Then I caution my Clients about the weight on the roof, the dangers of climbing up there, and tell them that if the sellers cannot prove that it has been inspected/serviced within the last 12 months (and the sellers never can), to have it inspected/serviced before close of escrow. That’s worked in 4½ years, and I do have many Clients who have gotten new systems, mainly because anything on a residential roof out here seems to be about 30 years old, perhaps time for a new one anyway just because they are more efficient and cut down on the energy bills.
Sid,
It is basically a packaged unit (furnace and a/c unit), but if this were a commercial building, I would recommend going on the roof to look at it.
Some items to check are: The bird screen on the intake for any damage, Should have a dis-connect box, check the filters and that there is a maintenance company that is keeping up with servicing of unit( should be marked on unit or screens), Make sure there are not any grease hoods or other exhaust vents near the intake of the unit. If on a built up roof make sure unit is not sitting on the roof (should be on raised curbs or wood blocks), condensate pan holding water, Mold in unit, Look very close around all roof penetrations for water leaks.
If I think of more things later I will post them
Make a note that a re-call was just issued for some combo unite,and yes i just got off the roof and a day later the re-call came out, sure am glade I get model & ser numbers, I had HEIL units
This is on a commercial building.
Thanks for your input. If anyone thinks of anything else to look for let me know.
Thanks
Sid
Where do you look for info on recalls?