Digital Gas Manometer

A gas manometer is used to measure gas pressure. In the United States pressure is typically measured in psi. Noritz highly recommends using a digital manometer and referencing it in “inches of water column.” There are 28 inches of water column in 1 psi. The gas pressures inside the heater will be set to a value that cannot be measured with an analog manometer because the values needed to be measured will be a fractions of “inches of water column” or in newer heaters a negative reading which will require a digital gas manometer to measure suction pressure. There are many manufacturers of gas manometers and can be typically purchased from an HVAC distributor or online.