ACV CC105, Installation & Maintenance Manual

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8. Gas Piping
8.2 Natural Gas
8.2.1 Pipe Sizing
Refer to Table 1 for schedule 40 metallic pipe length and diameter
requirements for natural gas, based on rated CHALLENGER input
(divide by 1,000 to obtain cubic feet per hour).
- Table 1 is based on Natural Gas with a specific gravity of 0.60
and a pressure drop through the gas piping of 0.30” w.c. [0.75
mbar].
- For additional gas sizing information, refer to ANSI Z223.1. For
Canadian installations refer to CAN/CSA B149.1.
8.2.2 Supply Pressure Requirements
Pressure required at the gas valve inlet supply pressure port: 1.
- Maximum 13” w.c. [32 mbar] at flow or no flow conditions
to the burner.
- Minimum 5” w.c. [13 mbar] during flow conditions to the
burner. Must be verified during start up and with all other
gas appliances operating within the gas piping service.
- Maximum gas inlet pressure must not be exceeded and
minimum gas inlet pressure is for the purpose of input
adjustment.
Install 100% lockup gas pressure regulator in the gas supply line 2.
if inlet pressure can exceed 13” w.c. [32 mbar] at any time.
Adjust the lockup pressure regulator for 13” w.c. [32 mbar].
8.2.3 Orifice Requirements
Refer to Table 2 for orifice required for appliance operation using
natural gas. All units come set up for natural gas installation with the
appropriate orifice pre-installed.
DO NOT adjust or attempt to measure gas valve outlet
pressure. The gas valve is factory-set for the correct
outlet pressure. This setting is suitable for natural and
propane gas and requires no field adjustment. At-
tempts by the installer to adjust or measure the gas
valve outlet pressure could result in damage to the
valve and can cause substantial property damage, seri-
ous injury, or death.
WARNING
Length of Pipe in
Feet
Capacity of Schedule 40 Metallic Pipe in Cubic Feet of Natural Gas Per Hour
(based on 0.60 specific gravity & 0.30" w.c. pressure drop)
SCH 40 1/2" 3/4" 1" 1-1/4" 1-1/2"
10 132 278 520 1050 1600
20 92 190 350 730 1100
30 73 152 285 590 890
40 63 130 245 500 760
50 56 115 215 440 670
75 45 93 175 360 545
100 38 79 150 305 460
150 31 64 120 250 380
Table 1: Gas Pipe Sizing - Natural Gas
Table 2: Natural Gas Orifice Requirements
CHALLENGER
Model
Natural
Orifice Size
Orifice
Marking
CC105 0.256" [6.50 mm] 650
CC125 0.285" [7.25 mm] 725
CC125H 0.217" [5.50 mm] 550