Carrier 48LC Series Installation Instructions Manual page 15

Fig. 20 - - Gas Piping Thru- - Base Connections
When installing the gas supply line, observe local codes
pertaining to gas pipe installations. Refer to the NFPA
54/ANSI Z223.1 NFGC latest edition (in Canada, CAN/CSA
B149.1). In the absence of local building codes, adhere to
the following pertinent recommendations:
1. Avoid low spots in long runs of pipe. Grade all pipe
1
/4- - in. in every 15 ft (7 mm in every 5 m) to prevent
traps. Grade all horizontal runs downward to risers.
Use risers to connect to heating section and to meter.
2. Protect all segments of piping system against physical
and thermal damage. Support all piping with appro-
priate straps, hangers, etc. Use a minimum of one
hanger every 6 ft (1.8 m). For pipe sizes larger than
1
/ - - in., follow recommendations of national codes.
2
3. Apply joint compound (pipe dope) sparingly and only
to male threads of joint when making pipe connec-
tions. Use only pipe dope that is resistant to action of
liquefied petroleum gases as specified by local and/or
national codes. If using PTFE (Teflon) tape, ensure
the material is Double Density type and is labeled for
use on gas lines. Apply tape per manufacturer's in-
structions.
4. Pressure- - test all gas piping in accordance with local
and national plumbing and gas codes before connect-
ing piping to unit.
NOTE: Pressure test the gas supply system after the gas
supply piping is connected to the gas valve. The supply
piping must be disconnected from the gas valve during the
testing of the piping systems when test pressure is in
excess of 0.5 psig (3450 Pa). Pressure test the gas supply
piping system at pressures equal to or less than 0.5 psig
(3450 Pa). The unit heating section must be isolated from
the gas piping system by closing the external main manual
shutoff valve and slightly opening the ground- - joint union.
Check for gas leaks
factory- - installed gas lines after all piping connections
have been completed. Use soap- - and- - water solution (or
method specified by local codes and/or regulations).
C08018
at the field- - installed and
WARNING
!
FIRE OR EXPLOSION HAZARD
Failure to follow this warning could result in personal
injury, death and/or property damage.
S Connect gas pipe to unit using a backup wrench to
avoid damaging gas controls.
S Never purge a gas line into a combustion chamber.
S Never test for gas leaks with an open flame. Use a
commercially available soap solution made
specifically for the detection of leaks to check all
connections.
S Use proper length of pipe to avoid stress on gas
control manifold.
NOTE: If orifice hole appears damaged or it is suspected
to have been redrilled, check orifice hole with a numbered
drill bit of correct size. Never redrill an orifice. A
burr- - free and squarely aligned orifice hole is essential for
proper flame characteristics.
Fig. 21 - - Orifice Hole
15
BURNER
ORIFICE
A93059