![background image](http://html.mh-extra.com/html/carrier/58cu0a-series/58cu0a-series_installation-start-up-operating-and-service-and-maintenance-instructions_2562744015.webp)
15
If pressure exceeds 0.5 psig (14--In. W.C.), gas supply pipe must
be disconnected from furnace and capped before and during
supply pipe pressure test. If test pressure is equal to or less than
0.5 psig (14--In. W.C.), turn off electric shutoff switch located on
furnace gas control valve and accessible manual equipment
shutoff valve before and during supply pipe pressure test. After
all connections have been made, purge lines and check for
leakage at furnace prior to operating furnace.
The gas supply pressure shall be within the maximum and
minimum inlet supply pressures marked on the rating plate with
the furnace burners ON and OFF.
UNION
SEDIMENT
TRAP
MANUAL
SHUTOFF
VALVE
(REQUIRED)
GAS
SUPPLY
A02035
Fig. 21 -- Typical Gas Pipe Arrangement
Table 5 – Maximum Capacity of Pipe*
NOMINAL IRON PIPE
INTERNAL DIAMETER
LENGTH OF PIPE --- FT. (M)
SIZE IN. (mm)
In. (mm)
10
20
30
40
50
1/2 (13)
0.622 (16)
175 (53)
120 (37)
97 (30)
82 (25)
73 (22)
3/4 (19)
0.824 (21)
360 (110)
250 (76)
200 (61)
170 (52)
151 (46)
1 (25)
1.049 (27)
680 (207)
465 (142)
375 (114)
320 (98)
285 (87)
1---1/4 (32)
1.380 (35)
1400 (427)
950 (290)
770 (235)
660 (201)
580 (177)
1---1/2 (38)
1.610 (41)
2100 (640)
1460 (445)
1180 (360)
990 (301)
900 (274)
* Cubic ft. of natural gas per hr for gas pressures of 0.5 psig (14---In. W.C.) or less and a pressure drop of 0.5---In. W.C. (based on a 0.60 specific gravity
gas). Ref: Chapter 6 current edition of ANSI Z223/NFPA 54.
Table 6 – Electrical Data
Unit Size
Volts-
Hertz-
Phase
Operating Voltage*
Range
Maximum
Unit Amps
Unit
Ampacity#
Minimum
Wire Size
AWG
Maximum
Wire
Length‡ ft
Maximum
Fuse or
CKT BKR†
Amps
Maximum
Minimum
040C17--12
115-60-1
127
104
11.4
12.6
14
29
15
060C17--16
115-60-1
127
104
11.4
12.6
14
29
15
080C21--20
115-60-1
127
104
17.8
18.9
12
30
20
100C21--20
115-60-1
127
104
17.8
18.9
12
30
20
* Permissible limits of the voltage range at which the unit operates satisfactorily.
# Unit ampacity = 125 percent of largest operating component’s full load amps plus 100 percent of all other potential operating components’ (EAC, humidifier,
etc.) full load amps.
{
Time---delay type is recommended.
}
Length shown is as measured one way along wire path between unit and service panel for maximum 2 percent voltage drop.
ELECTRICAL CONNECTIONS
ELECTRICAL SHOCK, FIRE OR EXPLOSION
HAZARD
Failure to follow safety warnings could result in dangerous
operation, serious injury, death or property damage.
Improper servicing could result in dangerous operation,
serious injury, death or property damage.
-- Before servicing, disconnect all electrical power to
furnace.
-- When servicing controls, label all wires prior to
disconnecting. Reconnect wires correctly.
-- Verify proper operation after servicing.
!
WARNING
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal
injury or death
.
Blower access panel door switch opens 115--v power to
control. No component operation can occur. Do not bypass
or close switch with panel removed.
!
WARNING
See Fig. 24 for field wiring diagram showing typical field 115--v
wiring. Check all factory and field electrical connections for
tightness.
Field--supplied wiring shall conform with the limitations of 63
_
F
(35
_
C) rise.