Pro’s and Con’s of Owning a Gas Furnace Sky Heating

4/12/2018 1 UNITS OF MEASURE •Inches of water column ("wc) - inches of water column is the traditional method for measuring natural gas or propane. There are 28 inches of water in 1 psi, so it is a fairly small amount of pressure •Pounds per square inch (psi) - used for measuring gas pressure in the distribution system and other areas where pressure exceeds the traditional 7" WC.. In Natural Gas lines, the gas pressure is typically 5" to 7" WC, but the furnace usually operates at pressures of 3.2" to 3.7" WC. The optimum setting can be found on the furnace rating plate. Depending on the altitude, a lower pressure may need to be set.

What Should Gas Furnace Pressure Be When Running? The correct gas furnace pressure when running depends on the type of fuel your furnace uses: For natural gas— The manifold pressure should be 3.5 inches of water column (WC). For propane gas — The manifold pressure typically ranges from 10 to 11 inches WC.. This article series gives the standard pressure ranges and pressure settings for LP gas, propane gas, and natural gas fuels, including pressures found in the distribution service piping, in the in-building gas piping, and at gas fired appliances such as gas stoves, clothes dryers, furnaces, boilers, and LP gas or natural gas fired water heaters.