Carrier 48TC - Page 10

10
The thru-- base gas connector has male and female threads.
The male threads protrude above the basepan of the unit;
the female threads protrude below the basepan.
Check tightness of c onnector lock nuts before connecting
gas piping.
Install a 1/2--in NPT street elbow on the thru--base gas
fitting. Attach a 1/2--in pipe nipple with minimum length
of 16--in (406 mm) (field--supplied) to the street elbow
and extend it through the access panel at the gas support
bracket. See Fig. 15.
EMBOSSMENT
BRASS FITTING
FOR 3-6 TON UNITS
SUPPORT
BRACKET
C08016
Fig. 15 -- Gas Line Piping for 3 to 6 Ton Units Only
Other hardware required to complete t he installation of
the gas supply line will include a manual shutoff valve, a
sediment trap (drip leg) and a ground--j oint union. A
pressure regulator valve may also be required (to convert
gas pressure from pounds to inches of pressure). The
manua l shutoff valve must be loca ted within 6--ft (1.83 m)
of the unit. The union, located in the final leg entering the
unit, must be located at least 9 -- in (230 mm) away from
the access panel to permit the panel to be removed for
service. If a regulator valve is installed, it must be located
a minimum of 4--ft (1220 mm) away from the unit’s flue
outlet. Some municipal codes require that the manual
shutoff valve be loc ated upstream of the sediment trap.
See Figures 16 and 17 for typical piping arrangements for
gas piping that has been routed through the sidewall of the
curb. See Fig. 18 for typical piping arrangement when
thru--base is used. Ensure that all piping does not block
access to the unit’s main control box or limit the required
working space in front of the control box.
9” (229mm) min
Union
Shut Off
Valve
Drip
Leg
Thru-Curb Adapter
Unit Base Rail
C07469
Fig. 16 -- Gas Piping
Drip
Leg
Shut Off
Valve
Union
Thru-Curb Adapter
Burner
Access
Panel
9” (229mm) min
Unit Base Rail
C07470
Fig. 17 -- Gas Piping
C08018
Fig. 18 -- Gas Piping Thru--Base Connections
48TC