Heat Transfer Phoenix, Installation & Operation Manual

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17
PREPARATION
PART 4: PREPARE WATER HEATER
(CONTINUED)
D. GAS TABLE
Refer to the below table 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 0.5 psi or Less and a
Pressure Drop of 0.3 Inch water Column
Gas Table
It is recommended that a soapy solution be used to detect leaks. Bubbles will appear on the pipe to
indicate a leak is present. The gas piping must be sized for the proper flow and length of pipe, to avoid
excessive pressure drop. Both the gas meter and the gas regulator must be properly sized for the total
gas load. If you experience a pressure drop greater than 1" WC, the meter, regulator or gas line is
undersized or in need of service. You can attach a manometer to the incoming gas drip leg, by
removing the cap and installing the manometer. The gas pressure must remain between 3.5" WC and
14" WC during stand-by (static) mode and while in operating (dynamic) mode at full output.
If an in-
line regulator is used, it must be a minimum of 10 feet from the Phoenix. It is very important that
the gas line is properly purged by the gas supplier or utility. Failure to properly purge the lines or
improper line sizing, will result in ignition failure.
This problem is especially noticeable in NEW LP
installations and also in empty tank situations. This can also occur when a utility company shuts off
service to an area to provide maintenance to their lines. The gas valve must not be replaced with a
conventional gas valve under any circumstances. As an additional safety feature in the Phoenix water
heater, the gas valve in this appliance has a flanged connection to the swirl plate and blower.
(Nominal
Iron Pipe Internal
Length of Pipe (Feet)
Size Diameter
(inches) (inches) 10 20 30 40 50 60 70 80 90 100 125 150 175 200
3/4 .824 278 190 152 130 115 105 96 90 84 79 72 64 59 55 BTU'S
1 1.049 520 350 285 245 215 195 180 170 160 150 130 120 110 100 PER
1 1/4 1.380 1,050 730 590 500 440 400 370 350 320 305 275 250 225 210
}
HOUR
1 1/2 1.610 1,600 1,100 890 760 670 610 560 530 490 460 410 380 350 320 x1,000