Tankless Water Heater Gas Supply Line Size

Gallons per minute gpm is the key when it comes to sizing tankless water heaters.

Tankless water heater gas supply line size.

Water heaters located in the garage may terminate on the garage floor with the same distance requirements cpc 505 6 cpc 505 4 508 5 608 5 t p does not discharge into a water heater drain pan. Branch 1 e tankless water heater 199 900 20 ft 1 g gas furnace 75 000 15 ft d branch main line 274 900 30 ft 1 branch 2 j gas dryer 25 000 20 ft h gas range 55 000 30 ft k gas logs 40 000 10 ft b c branch main line 120 000 45 ft main trunk a main trunk line 394 900 20 ft 1. In all cases a near 200 000 btu gas appliance will require a minimum of a inch gas supply line. Tables 2 and 3 provide the capacity by pipe size and length based on the maximum allowable pressure drops.

Since tankless water heaters supply endless hot water you don t have to worry about capacity but instead think in terms of water flow rate. Like a hot water tank for 5 people will require at least a 60 gallon tank. Typically the gas piping has to be upgraded to support the tankless water heater due to the volume of fuel that is required. Cpc508 5 provide gas line sizing calculations and isometric riser diagram of the gas delivery piping system for the equipment with permit application.