To properly size IP gas regulators for a home, start by finding and writing down the BTU or SCF specifications of the gas appliance from the operational instructions. Determine the size of the regulator by gauging the gas inlet pressure.
The gas meter for any home typically has the proper inlet pressure posted on it for easy access. This information is also obtained by calling or emailing the gas company. Next, determine the outlet pressure for the appliance you are fitting. Many appliances list this specification in the operational instructions, as well. The proper regulator size is a combination of the inlet and outlet gas pipe diameters, and many times the sizes are the same. Finally, choose the type of gas, either natural or propane, for which the regulator is fitted.
Check with the gas company before turning the gas on for any appliance to be sure that an inspection is not required. Keep gas pressure low for safety. The regulator size is vital, as a large regulator leads to leaks that can cause explosions, and a small regulator inhibits proper operation. Always check that the regulator is suited to the right type of gas, as each type has a specific kind of regulator.