Carrier 48KHA - Manual (Page 6)

7. Pressure-test all gas piping in accordance with loceil
and national plumbing and gas codes before connecting
piping to unit.
NOTE: When pressure-testing the gas supply system
after the gas supply piping has been connected to the
unit gas valve, the supply piping must be disconnected
from the gas valve during any pressure testing of the
piping systems at test pressures in excess of 0.5 in.
psig. When pressure testing the gas supply piping sys­
tem at test pressures equal to or less than 0.5 in. psig,
the unit heating section must be isolated from the gas
piping system by closing the external main manual
shutoff valve and slightly opening ground-joint union.
A CAUTION
Unstable operation may occur, peirticularly under high-
wind conditions, when gas valve and manifold assembly
are forced out of position while connecting improperly
routed, rigid gas piping to gas valve. Use a backup
wrench when making connection to avoid strain on, or
distortion of, gas control piping.
8. Where permitted by local codes, use an approved corru­
gated metal tubing gas connector between rigid gas
piping and unit manual shutoff.
A WARNING
Never use a match or other open flame when checking
for leaks. Failure to adhere to this warning may cause
an explosion.
9. Check for gas leeiks at eJl field-installed and 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).
Step 3—Make Duct Connections— Model 48KHA,KLA
has duct flanges on the supply- and return-air openings on
side of unit. See Fig. 4 for connection sizes and locations.
A WARNING
The design and installation of duct system must be in
accordance with standards of National Fire Protection
Association for installation of non-residence type air
conditioning and ventilating systems. NFPA No. 90; or
residence-type NFPA No. 90B; and/or local codes and
ordinances.
2. Use a flexible transition between rigid ductwork and
unit to prevent transmissions of vibration. The transi­
tion may be screwed or bolted to duct flanges. Use suit­
able gaskets to ensure a weathertight and air-tight
seal.
3. Install external, field-supplied air filter(s) in return-air
ductwork where it is easily accessible for service. Rec­
ommended filter sizes are shown in Table 2.
4. Size all ductwork for maximum required airflow (either
heating or cooling) for unit being installed. Avoid
abrupt duct size increases or decreases.
5. Adequately insulate and weatherproof all ductwork
located outdoors. Insulate ducts passing through an
unconditioned space, and use a vapor barrier in accord­
ance with the latest issue of SMACNA and NE SC A
minimum installation standards for heating and air
conditioning systems. Secure all ducts to building
structure.
6. Flash, weatherproof and vibration-isolate all openings
in building structure in accordance with local codes and
good building practices.
Table 2—Filter Sizes (Field Supplied),
(Sq In.)*
STANDARD CLEANABLEOR
MODEL 48- DISPOSABLE HIGH CAPACITY
TYPE TYPE
KLA118310BE 302 202
KHA024310BF 454 303
KLA124310BE 384 257
KHA030310BF 480 320
KLA130310BE 480 320
KHA036310BF 694 462
KHA136510CE 576 384
KHA036510CF 694 462
KHA136310BE 576 384
KLA136510CE 576 384
KLA136610CE 576 384
KLA136310BE 576 384
KHA042310BF 694 462
KHA042510CF 694 462
KLA142510CE 672 448
KLA142310BE 672 448
KHA048310BF 768 512
KHA048510CF 768 512
KLA148510CE 768 512
KLA148610CE 768 512
KLA148310BE 768 512
KHA060310BF 960 640
KLA160310BE 960 640
*Required air filter areas shown are based on the ARI-rated cooling air­
flow or the heating airflow at a velocity of 300 fpm depending on
whichever value is larger. Air filter pressure drop should not exceed 0 08
, in wg
Step 4—Make Wiring Connections
Adhere to the following requirements when selecting, sizing
tmd installing duct system;
1. Select and size ductwork, supply-air registers and
return-£ur grilles according to ASHRAE recommenda­
tions emd as presented in Carrier System Design Man­
ual, Part 2.
A CAUTION
When duct system fastening holes are drilled into side
of Model 48KHA,KLA instead of the unit duct flanges,
use extreme care to avoid puncturing coil or coil tubes.
A WARNING
Unit cabinet must have an uninterrupted, unbroken
electrical ground to minimize the possibility of personeil
injury if an electrical fault should occur. This ground
may consist of electrical wire connected to unit ground
lug in control compartment, or conduit approved for
electrical ground when installed in accordance with
National Electrical Code ANSI/NFPA 70-1984 and
local electriced codes. Do not use gas piping as an elec­
trical ground. Failure to follow this warning could
result in the installer being held liable for personal
injury of others.