HVAC Procedure and Performance Guide

Measure pressure drop across coil or filter using manometer and probes


Air-pressure differential across coil or filter must be accurately measured using probes and manometer or static-pressure gage as recommended in recognized publications.  Applicable safety procedures must be followed.


  1. Review manufacturer’s specifications.
  2. Collect tools, equipment and materials.
  3. Put on safety and protective equipment and apparel.
  4. Inspect equipment and determine locations for insertion of probes.
  5. Prepare openings for probes on either side of filter or coil.
  6. Ensure that system is operating at rated air-flow.
  7. Insert probes and read differential pressure across coil or filter.
  8. Record measurements.
  9. Reseal duct openings.
  10. Leave equipment in required operating status.
  11. Remove safety and protective equipment and apparel.
  12. Gather tools, equipment and leftover materials, and leave work site clean.