Westinghouse WGR050LP076, Руководство по установке

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WHL-001 REV. 9.3.14
The gas supply shall have a maximum inlet pressure of less than 14" water
column (350 mm), ½ pound pressure (3.5 kPa), and a minimum of 3.5" water
column. The entire piping system, gas meter and regulator must be sized
properly to prevent pressure drop greater than 0.5" WC as stated in the
National Fuel Gas Code. This information is listed on the rating plate.
It is very important that you are connected to the type of gas as noted on the
rating plate: "LP" for liquefied petroleum, propane gas, or "Nat" for natural or
city gas. All gas connections must be approved by the local gas supplier or
utility, in addition to the governing authority, prior to turning the gas supply
on.
Do not remove the adaptor in
Figure 20
! It is mandatory that this fitting is used
for connection to a field fabricated drip leg per the National Fuel Gas Code.
You must ensure that the entire gas line to the connection at the water heater
is no smaller than ½”.
Once all inspections have been performed, the piping must be leak tested. If
the leak test requirement is a higher test pressure than the maximum gas
inlet pressure, you must isolate the heater from the gas line to continue leak
testing. To do this, you must turn off the factory and field-installed gas cocks.
This will minimize the possibility of damaging the gas valve. Failure to do so
may damage the gas valve. In the event the gas valve is exposed to a
pressure greater than ½ PSI, 14" water column, the gas valve must be replaced. Never use an open flame (match, lighter, etc.) to
check gas connections.
UL recognized fuel gas detectors are recommended in all enclosed propane and natural gas applications where there is a potential for
an explosive mixture of fuel gas to accumulate. The installation of these detectors should be made in accordance with the detector
manufacturer
’s recommendations, and/or local laws. Failure to install fuel gas detectors in these applications could result in fire,
explosion, property damage, severe personal injury, or death.
A. GAS PIPING
Run the gas supply line in accordance with all applicable codes. Locate and install manual shutoff valves in accordance with local and
state requirements.
Support gas supply piping with hangers, not by the heater or its accessories. The heater gas valve and blower will not support the
weight of the piping. Make sure the gas piping is protected from physical damage and freezing, where required. Failure to follow these
instructions could result in gas leakage, and result in fire, explosion, property damage, severe personal injury, or death.
Do not use Teflon tape on gas line pipe thread. Use a pipe compound rated for use with natural and propane gases. Apply sparingly on
male pipe ends, leaving the two end threads bare. Failure to follow these instructions could result in gas leakage, and result in fire,
explosion, property damage, severe personal injury, or death.
B. GAS TABLE
Refer to the table below to size the supply piping to minimize pressure drop between meter or regulator and unit.
Maximum capacity of pipe in cubic feet of gas per hour for gas pressures of .5 psi or less and a pressure drop of .3 inch water column.
Nominal Iron
Pipe Size (In.)
Internal
Dia. (In.)
Length of Pipe (Feet)
BTU’s
Per Hour
x
1,000
10 20 30 40 50 60 70 80 90 100 125 150 175 200
½
¾ .824 278 190 152 130 115 105 96 90 84 79 72 64 59 55
1 1.049
520 350 285 245 215 195 180 170 160 150 130 120 110 100
1 ¼ 1.380
1,050 730 590 500 440 400 370 350 320 305 275 250 225 210
Table 9
– Source – ANSI Z223.1
Figure 20
–Gas Connection