Commercial HVAC Guides
Field-tested guidance on rooftop units, hydronics, chillers and controls — written by the technicians who service them.
Rooftop & Split · Pillar guideWhy Commercial Rooftop Units Short CycleA rooftop unit that starts and stops every few minutes is not a comfort problem. It is a compressor problem. How to tell which of five causes you have.Read the guide →Rooftop & Split · GuideEconomizer Damper Stuck Open: Cold Building, High Gas UseCold drafts all winter and gas use up year over year, with no change in occupancy. The economizer damper is open when it should be shut. How to prove it.Read the guide →Rooftop & Split · GuideWater Staining the Ceiling Under a Rooftop UnitCeiling tiles staining under the rooftop, and the unit stopped cooling. Those are one fault, not two, and clearing the drain may not fix it.Read the guide →