Before installing a new gas cooktop in your home, you need to determine if the gas supply line for it will be adequate. Follow the directions below to learn the minimum supply line diameter your new gas cooktop will need.
BTU to Cubic Feet per Hour
Gas supply is measured in cubic feet per hour. Appliance ratings for energy, on the other hand, are provided in British Thermal Units. Divide the BTU measurement by 1,000 to get an approximate CFH. A gas cooktop rated at 45,000 BTU would take 45 CFH of gas supply.
Pipe Size Needed
On average a house using 300 to 400 CFH for all its needs requires 1.25-inch pipe from the gas meter to where the devices that use it branch off from the pipeline. A pipe flow conversion chart will help you calculate your total and individual device usage.
For Each Specific Device
The pipe flow must be narrower for each device to distribute the gas flow. For your gas cooktop at 45 CFH, you will need just a 1/2-inch supply line. This diameter line will provide 56 CFH to your cooktop, which is a bit more than needed. If you use a gas oven as well, totaling 75 to 80 CFH, this takes a 3/4-inch diameter line.