inH2O

Units & Measurements abbreviation · Engineering Unit

inH2O stands for Inches of water column, an engineering unit abbreviation.

A small pressure unit equal to a one-inch column of water, about 249 pascals. HVAC duct static pressure, natural gas appliance pressure and chimney draft are measured in inches of water in the US.

Example: Set the gas valve outlet pressure to 3.5 inH2O for natural gas.

Usage notes

Also written in. w.c. (water column) or in WC. Residential natural gas is typically delivered at about 7 inches of water column, roughly a quarter psi, and appliances regulate it to around 3.5 inches; propane appliances run near 11 inches. Duct systems are commonly designed for about 0.5 inH2O total static pressure.

Related abbreviations

More engineering unit abbreviations

• GWh – Gigawatt-hour
• hp – Horsepower
• hPa – Hectopascal
• HRC – Rockwell hardness C (scale)
• Hz – Hertz
• in-lb – Inch-pound
• inHg – Inches of mercury
• J – Joule
• K – Kelvin
• kcal – Kilocalorie
• kgf – Kilogram-force
• kHz – Kilohertz

See all 103 engineering unit abbreviations →

Edited by the AbbreviationList.com team. Spotted an error or a missing meaning? Contact us.