Below are the recommended steps to perform on site to gather existing HVAC system information:
1. Ask if there are existing plans of the HVAC systems.
These sometimes can be found on site.
2. Take some photos of the existing building for load calculations.
Photos are best if taken further back for overview of building type.
Photos of glass and overhangs are good.
Interior photos that show wall heights and glass.
Interior photos of RCP that show diffusers in grid (especially when ceiling to remain).
3. Document Existing HVAC Systems
A sketch of the building and HVAC equipment is very helpful.
Take photo from further back for locations.
Take photos of all HVAC tags with model/serial numbers (locations should be shown on sketch that corresponds to photo)
Typical HVAC Equipment you may see on site:
Rooftop unit with gas heat
Split System Condensing Units on Roof (Relief or Intake Hood in Background)
Larger Condensing Unit
Roof Exhaust Fan
Kitchen Hood Exhaust Fan
Walk-In Refrigerator/Freezer Condensers
Variable-Air- Volume (VAV) – Typically installed on interior zones with no heating required
Power-Induction Unit (PIU) or Fan-Powered VAV – Typically installed with electric heat and installed in perimeter zones where heating is required
Air-Handling Unit (Chilled Water)
Water-cooled chillers and pumps
Cooling Towers
And, please don’t tell your client they can reuse all the existing equipment…