What is the purpose of a manometer or digital manometer in gas piping?

• A. To measure gas pressure and ensure it is within the appliance’s required range.
• B. To measure airflow in the duct
• C. To measure temperature
• D. To measure humidity

Answer: (A)

The main idea is that a manometer measures the gas pressure in the piping so you can verify it stays within the appliance’s required range. Gas burners rely on a specific pressure to mix fuel with air properly and to ignite reliably. Using a manometer (or a digital one) lets you read the pressure at the supply or at the appliance’s gas valve and confirm it matches the manufacturer’s spec. If pressure is too low, the burner may not light or flame quality will suffer; if too high, it can cause overfiring or safety shutoffs. This tool is not for measuring airflow, temperature, or humidity, which are checked with flow meters, thermometers, or hygrometers, respectively.