All Field Gas Piping Must Be Pressure/Leak Tested Prior To; Operation. Never Use An Open Flame. Use A Soap Solution Or; Gas Pressure To Appliance Controls Must Never Exceed 14" W.c. (1/2 Psi); The Appliance, As Indicated On The Serial Plate, Must Not Exceed The Rated Input By More Than - Modine Manufacturing PDP Installation And Service Manual

installation

Gas connections

WARNING

1. All field gas piping must be pressure/leak tested prior to

operation. Never use an open flame. Use a soap solution
or equivalent for testing.
2. Gas pressure to appliance controls must never exceed 14"
W.C. (1/2 psi).
3. To reduce the opportunity for condensation, the minimum
sea level input to the appliance, as indicated on the serial
plate, must not be less than 5% below the rated input, or 5%
below the minimum rated input of dual rated units.
CAUTION
Purging of air from gas supply line should be performed as
described in ANSI Z223.1 - latest edition "National Fuel Gas
Code", or in Canada in CAN/CGA-B149 codes.
IMPORTANT
To prevent premature heat exchanger failure, the input to
the appliance, as indicated on the serial plate, must not
exceed the rated input by more than 5%.
1. Installation of piping must conform with local building
codes, or in the absence of local codes, with the National
Fuel Gas Code, ANSI Z223.1 (NFPA 54) - Latest Edition.
In Canada, installation must be in accordance with CAN/CGA-
B149.1 for natural gas units and CAN/CGA-B149.2 for
propane units.
2. Piping to units should conform with local and national
requirements for type and volume of gas handled, and
pressure drop allowed in the line. Refer to Table 11.1 to
determine the cubic feet per hour (cfh) for the type of gas
and size of unit to be installed. Using this cfh value and
the length of pipe necessary, determine the pipe diameter
from Table 7.1. Where several units are served by the
table 7.1 - Gas Pipe capacities
length
of Pipe 1/"
(feet) natural Propane
10 132 83
20 92 58
30 73 46
40 63 40
50 56 35
60 50 32
70 46 29
80 43 27
90 40 25
100 38 24
125 34 21
150 31 20
Gas Pipe capacities (up to 14" W.c. Gas Pressure through schedule 40 Pipe)
cubic feet per Hour with Pressure drop of 0.3" W.c.
natural Gas - specific Gravity - 0.60
Propane Gas - specific Gravity - 1.50
3/4"
natural Propane natural
278 175 520
190 120 350
152 96 285
130 82 245
115 72 215
105 66 195
96 60 180
90 57 170
84 53 160
79 50 150
72 45 130
64 40 120
same main, the total capacity, cfh and length of main must
be considered. Avoid pipe sizes smaller than 1/2". Table
7.1 allows for a 0.3" W.C. pressure drop in the supply
pressure from the building main to the unit. The inlet
pressure to the unit must be 6-7" W.C. for natural gas and
11-14" W.C. for propane gas. When sizing the inlet gas
pipe diameter, make sure that the unit supply pressure
can be met after the 0.3" W.C. has been subtracted. If the
0.3" W.C. pressure drop is too high, refer to the Gas
Engineer's Handbook for other gas pipe capacities.
3. Install a ground joint union with brass seat and a manual
shut-off valve adjacent to the unit for emergency shut-off
and easy servicing of controls, including a 1/8" NPT
plugged tapping accessible for test gauge connection
(see Figure 7.1).
4. Provide a sediment trap before each unit and in the line
where low spots cannot be avoided (see Figure 7.1).
5. When Pressure/Leak testing, pressures above 14" W.C.
(1/2 psi), close the field installed shut-off valve, disconnect
the appliance and its combination gas control from the
gas supply line, and plug the supply line before testing.
When testing pressures 14" W.C. (1/2 psi) or below, close
the manual shut-off valve on the appliance before testing.
figure 7.1 - recommended sediment trap/manual
shut-off valve installation - side or Bottom Gas
connection
GAS
SUPPLY LINE
MIN.
➀ Manual shut-off valve is in the "OFF" position when handle is perpendicular
to pipe.
Pipe diameter
1" 1-1/4"
Propane natural Propane
328 1050 662
221 730 460
180 590 372
154 500 315
135 440 277
123 400 252
113 370 233
107 350 221
101 320 202
95 305 192
82 275 173
76 250 158
6-580.4
GAS
GROUND
SUPPLY LINE
JOINT
UNION
W/ BRASS
➀
SEAT
MANUAL GAS
SHUT-OFF VALVE
TO
CONTROLS
PLUGGED
3" 1/8" NPT TEST
GAGE CONNECTION
SEDIMENT
TRAP
1-1/"
natural Propane natural
1600 1008 3050
1100 693 2100
890 561 1650
760 479 1450
670 422 1270
610 384 1150
560 353 1050
530 334
490 309
460 290
410 258
380 239
"
Propane
1922
1323
1040
914
800
725
662
990 624
930 586
870 548
780 491
710 447
7