Watts Aerco AM Series, Operation & Maintenance Manual

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AM Series Pool Heater User Manual
SECTION 6: INSTALLATION - NATURAL GAS
OMM-0111_B: • GF-146-P • 10/29/2019
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The unit is shipped ready to fire on natural gas. Check appliance rating plate to determine which
fuel the appliance is set for. If set to natural gas, it may be converted to propane gas following
instructions in Section 7.9 of AM Series User Manual GF-146.
6.4 Natural Gas Pipe Sizing
Refer to the table below for pipe lengths and diameters. For additional gas pipe sizing information,
refer to ANSI Z223.1 (or B149.1 for Canadian installations).
TABLE 7-1: Gas Pipe Capacity for Natural Gas
Iron Pipe Size (in)
Nominal: 3/4 1 1 1/4 1 1/2 2 2 1/2 3 4
Actual ID: 0.824 1.049 1.380 1.610 2.067 2.469 3.068 4.026
Length (ft
) Capacity in Cubic Feet of Gas per Hour
10 273 514 1060 1580 3050 4860 8580 17500
20 188 353 726 1090 2090 3340 5900 12000
30 151 284 583 873 1680 2680 4740 9660
40 N/A 243 499 747 1440 2290 4050 8270
50 N/A 215 442 662 1280 2030 3590 7330
60 N/A 195 400 600 1160 1840 3260 6640
70 N/A 179 368 552 1060 1690 3000 6110
80 N/A 167 343 514 989 1580 2790 5680
90 N/A 157 322 482 928 1480 2610 5330
100 N/A 148 304 455 877 1400 2470 5040
125 N/A 131 269 403 777 1240 2190 4460
150 N/A 119 244 366 704 1120 1980 4050
175 N/A N/A 224 336 648 1030 1820 3720
200 N/A N/A 209 313 602 960 1700 3460
250 N/A N/A 185 277 534 851 1500 3070
NOTE:
Maximum pipe capacity is based on a 0.60 specific gravity gas at a pressure of 0.5 PSIG and
a 0.3” W.C. pressure drop.
6.5 Natural Gas Supply Pressure Requirements
•
Install 100% lockup gas pressure
regulator in supply line if inlet pressure can exceed 13”W.C.
at any time. Adjust lockup regulator for 13” W.C. maximum.
•
Pressure required at the gas valve inlet pressure port:
o
Maximum 13” W.C. with no flow (lockup) or with appliance off.
o
Minimum 3” W.C. with gas flowing (verify during high fire).
6.6 Propane Gas Pipe Sizing
Contact gas supplier to size pipes, tanks, and 100% lockup propane gas pressure regulator.
6.7 Propane Gas Supply Pressure Requirements
•
Adjust propane supply regulator provided by the gas
supplier for 13”W.C. maximum pressure.
•
Pressure required at the gas valve inlet pressure port:
o
Maximum 13” W.C. with no flow (lockup) or with appliance off.