For this guy, HVAC (Heating, Ventilation, and Air Conditioning) start-up comes after the electrician and plumbing crews have trimmed out (See Step 31). As the homeowner/general contractor I may need to facilitate a little dialogue between these different crews, maybe even get them on the phone together if someone’s not on site, but for the most part I just let the heating and air team in the house and stay out of their way. They’ll know what to do and all I might do is slow them down by asking too many questions while they work.
The electrician will run power to any HVAC unit(s) and if the equipment is gas powered, that gas line work will be completed by the plumber. The HVAC team can’t finish their part without the other two.
The heating and air crew will have some trim out of their own; vent covers for registers, return air grille(s) and filter(s) as well as installation of thermostat(s). These activities are not going to take a lot of time. They’re important and will help make each room look complete, but they’ll be done quickly. The HVAC contractor could easily knock this all out while he’s waiting for the plumber or electrician to tie up any loose ends before he confirms that their unit is ready to heat and cool the house. Then, be around and ready to ask questions about operating the unit after they have everything in working order.
Finally, be ready to write a check once the crew passes any required inspections. Larger companies will probably give you thirty days to pay, but smaller operators will need to be paid as soon as they're finished. And when you hand over the payment, this is the time to accept paperwork such as the owner's manual and warranty certificate's. Make sure the technician has filled in any model and serial number info. then fill out your part and mail it in.