Drip Leg / Sediment Trap Needed In Your San Antonio Area Home

A Drip Leg (Sediment Trap) is needed at your Gas Water Heater & Furnace

Drip Leg / Sediment Trap    
A sediment trap (drip leg) must be used on both propane and natural gas line installations, to trap condensate, oil, metal shavings and other debris and impurities, which might otherwise clog the burner orifice or lodge in the gas valve. Proper installation of the needed drip leg will help maintain the proper functioning of the gas furnace and water heater units but also help prevent a safety hazard.
The sediment trap should be installed as close to the water heater or furnace inlet as possible.  

The Drip Leg / Sediment Trap (called by either name) is a gas line safety device required by The National Fuel Gas Code, ANSI Z223.1 / NFPA 54 and by the IRC (International Residential Code), the UPC (Uniform Plumbing Code) and the NFPA (National Fire Protection Agency) along with most if not all manufacturers of large gas appliances including water heaters and furnaces, boilers and gas pool heaters and is listed in the installation procedures of the appliance manual/ installation instructions.
Not installing the appliances per manufacturers installation requirements may void the warranty
on water heaters and furnaces. 
      Furnace manufacturer requirements for drip leg - sediment trap installation.
The above photo image shows the installation reguirements from a furnace manufacturers manual for the sediment trap (drip leg) at the gas line. The image below shows a manufacturers requirements for the sediment trap for the water heater which will not only help maintain proper functioning but also per manufacturer will assist in preventing a Fire and / or Explosion Hazard. 
     Water Heater Manufacturers drip leg sediment trap installation instructions

The national codes for gas piping don’t require sediment traps at such appliances as-
 illuminating appliances, ranges, clothes dryers, or outdoor grills. 
 This leaves furnaces and water heaters that are required to have them in your San Antonio area home.      
International Residential Code (IRC) 2006- G2419
     San Antonio Drip Leg 
IRC G2419.4 states that-
"Where a sediment trap is not incorporated as part of the gas utilization equipment, a sediment trap shall be installed downstream of the equipment shut off valve as close to the inlet of the equipment as practical".
  Drip leg - sediment trap missing at gas water line of water heater Drip Leg- Sediment Trap installed at gas water heater   
Image at left shows a gas water heater without the required Drip Leg at the gas line at a San Antonio area New Home Inspection. Image at right shows the gas line drip leg after installation by the Builders plumber after the inspection revealed it was not installed as required.
Image below shows the UPC (Uniform Plumbing Code) requirements.

                          UPC- Uniform Plumbing Code Gas Supply Drip Leg


By Joseph W. Keresztury- JWK Inspections and Consulting 
San Antonio area Home Inspector, Consultant and New Home Construction Specialist

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