State Industries Commercial Gas Water Heater Gas Piping, Venting Through a Roof CONT’D

Installing the New Water Heater (cont’d)

VENTING THROUGH A ROOF (CONT’D) Gas Piping

2.Only 3″ ABS Schedule 40 piping and fittings are acceptable materials on the first five feet of the outlet vent system.

3.3″ PVC, ABS, or CPVC Schedule 40 piping and fittings are acceptable materials for the inlet vent system and for the out- let vent system after the first five feet.

4.It cannot be connected to existing vent piping or chimney.

5.It must terminate vertically to the outdoors.

6.The total vertical and horizontal vent runs cannot exceed the maximum length with a maximum number of 90˚ elbows as specified in the table below. If more elbows are required, the venting distance must be reduced 5 feet for every 90° elbow.

3″ DIA. VENTS	NUMBER OF 90˚ DEG.
MAX. LENGTH (FT.)	ELBOWS*
45	1
40	2
35	3

*NOTE: Two 45˚ elbows are equivalent to one 90˚ elbow. One 90˚ elbow equals 5 feet of equivalent vent length.

TOTAL VERTICAL AND

HORIZONTAL RUNS - SEE

CHART ABOVE (ITEM 6).

WARNING

Make sure the gas supplied is the same type listed on the model rating plate. The inlet gas pressure must not exceed 10.5 in. water column (2.6kPa)for natural gas or 13 in. water column (3.2 kPa) for propane (L.P.) gas. The minimum inlet gas pressure listed on the rating plate is for the purpose of input adjustment.

WARNING

If the gas control valve is subjected to pressure exceed- ing 1/2 pound per square inch (3.5kPa), the damage to the gas control valve could result in a fire or explosion from leaking gas.

WARNING

If the main gas line shutoff serving all gas appliances is used, also turn “OFF” the gas at each appliance. Leave all gas appliances turned “OFF” until the water heater installation is complete.

A gas line of sufficient size must be run to the water heater. Consult the latest edition of National Fuel Gas Code ANSI Z223.1, also referred to as NFPA 54 and the gas company concerning pipe size.

There must be:

—A readily accessible manual shut off valve in the gas sup- ply line serving the water heater, and

—A drip leg (sediment trap) ahead of the gas control valve to help prevent dirt and foreign materials from entering the gas control valve.

—A flexible gas connector or a ground joint union between the shutoff valve and control valve to permit servicing of the unit.

Be sure to check all the gas piping for leaks before lighting the water heater. Use a soapy water solution, not a match or open flame. Rinse off soapy solution and wipe dry.

When installed at elevations above 2,000 feet, input rat- ings should be reduced at the rate of 4 percent for each 1,000 feet above sea level.

WARNING

The appliance and its individual shutoff valve must be disconnected from the gas supply piping system during any pressure testing of that system at test pressures in excess of 1/2 pound per square inch (3.5kPa).

The appliance must be isolated from the gas supply pip- ing system by closing its individual manual shutoff valve during any pressure testing of the gas supply piping sys- tem at test pressures equal to or less than 1/2 pound per square inch (3.5kPa).

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