HTP PHR199-55C - Manual (Page 53)

53
LP- 325 REV. 3.21.14
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 29! 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 appliance is no smaller than ¾".
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
appliance 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.
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.
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
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
1 ½ 1.610 1,600 1,100 890 760 670 610 560 530 490 460 410 380 350 320
Table 10 – Source – ANSI Z223.1
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 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. 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 appliance. 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, the
gas valve in this appliance has a flanged connection to the swirl plate
and blower.
Figure 29 – Phoenix Gas Connection - LP-179-Q