Mike PleziaInside service technician, Clark Associates · Commercial Equipment, HVAC, and Refrigeration professional

The Manometer: When Numbers Beat Guesses

16 Oct 2026 · 1 min

Watch on YouTube

1:00

In this instructional clip, the speaker introduces the manometer as an essential tool for HVAC technicians. He explains that a manometer measures pressure—both gas pressure in the fuel line and static pressure in the airflow system. For heating calls, the device is used to verify that gas supply pressure meets the manufacturer’s specifications before and after the regulator, highlighting the problems caused by pressures that are too low or too high. On the airflow side, the manometer reads external static pressure across the air handler, indicating how hard the blower is working against the ductwork. The speaker notes that either a digital or a simple inclined manometer can be used, emphasizing that obtaining a numeric reading is far more reliable than guessing. He stresses the safety importance of measuring gas pressure on every furnace tune‑up and encourages technicians to share this knowledge with peers.

Chapters

Hey, are you new to the trades? Here's something you may not know about the manometer and why it belongs in your tool bag. A manometer measures pressure, specifically gas pressure and static pressure. On a heating call, it tells you whether the gas supply pressure is within the manufacturer's specification before the regulator and after. Too low and the burners won't fire correctly. Too high and you have a different problem. On the airflow side, a manometer measures external static pressure across the air handler. That reading tells you how hard the blower is working against the duct system. You can use a digital manometer or a simple inclined manometer. Either way, it gives you a number, and numbers beat guesses every time. If you're not measuring gas pressure on every furnace tune-up, you're skipping a safety check. Now that you know, you can help someone else know.