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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). Pres
-
sure 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 at the 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).
NOTE: If orifice hole appears damaged or it is suspected to have
been re-drilled, check orifice hole with a numbered drill bit of cor
-
rect size. Never re-drill an orifice. A burr-free and squarely
aligned orifice hole is essential for proper flame characteristics.
See Fig. 26.
Fig. 26 —
Orifice Hole
Step 11 —
Install External Condensate Trap and
Line
The unit has one
3
/
4
-in. condensate drain connection on the end of
the condensate pan and an alternate connection on the bottom. See
Fig. 27. Unit airflow configuration does not determine which
drain connection to use. Either drain connection can be used with
vertical or horizontal applications.
To use the alternate bottom drain connection, remove the red
drain plug from the bottom connection (use a
1
/
2
-in. square sock
-
et drive extension) and install it in the side drain connection.
The piping for the condensate drain and external trap can be com
-
pleted after the unit is in place. See Fig. 28.
All units must have an external trap for condensate drainage. In
-
stall a trap at least 4-in. (102 mm) deep and protect against
freeze-up. If drain line is installed downstream from the external
trap, pitch the line away from the unit at 1-in. per 10 ft
(25 mm in 3 m) of run. Do not use a pipe size smaller than the
unit connection (
3
/
4
-in.).
Fig. 27 —
Condensate Drain Pan (Side View)
Fig. 28 —
Condensate Drain Piping Details
Step 12 —
Make Electrical Connections
NOTE: Field-supplied wiring shall conform with the limitations
of minimum 63°F (33°C) rise.
FIELD POWER SUPPLY
For those units without through-the-curb power, conduit must be
used to route the main power from the condenser end, via the
power entry in the corner post of the unit (see Fig. 29 and 30) to
either the factory option disconnect or the bottom of the control
box. A one-inch conduit is provided wrapped around compres
-
sor. A second conduit is provided with factory-installed powered
convenience outlet. For those units that require conduit larger
than 1-in., it must be field supplied. Fig. 29 and 30 show the wire
routings.
WARNING
Failure to follow this warning could result in personal injury,
death and/or property damage.
• Connect gas pipe to unit using a backup wrench to
avoid damaging gas controls.
• Never purge a gas line into a combustion chamber.
• 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.
• Use proper length of pipe to avoid stress on gas control
manifold.
BURNER
ORIFICE
WARNING
ELECTRIC SHOCK HAZARD
Failure to follow this warning could result in personal injury or
death.
Unit cabinet must have an uninterrupted, unbroken electrical
ground to minimize the possibility of personal injury if an
electrical fault should occur. This ground may consist of elec
-
trical wire connected to unit ground lug in control compart
-
ment, or conduit approved for electrical ground when installed
in accordance with NEC; ANSI/NFPA 70, latest edition (in
Canada, Canadian Electrical Code CSA [Canadian Standards
Association] C22.1), and local electrical codes.
DRAIN
(FACTORY-INSTALLED)
PLUG
CONDENSATE PAN (SIDE VIEW)
STANDARD
SIDE DRAIN
ALTERNATE
BOTTOM DRAIN
NOTE: Trap should be deep enough to offset maximum unit static
difference. A 4-in. (102 mm) trap is recommended.
MINIMUM PITCH
1” (25mm) PER
10’ (
3
m) OF LINE
BASE RAIL
OPEN
VENT
TO ROOF
DRAIN
DRAIN PLUG
ROOF
CURB
SEE NOTE
3
in. (76 mm)
MIN
Summary of Contents for 48LC Series
Page 5: ...5 Fig 2 Unit Dimensional Drawing Size 08 Unit ...
Page 6: ...6 Fig 2 Unit Dimensional Drawing Size 08 Unit cont ...
Page 7: ...7 Fig 3 Unit Dimensional Drawing Size 09 and 12 Units ...
Page 8: ...8 Fig 3 Unit Dimensional Drawing Size 09 and 12 Units cont ...
Page 11: ...11 Fig 6 Roof Curb Details Size 08 12 Units ...
Page 21: ...21 Fig 34 48LC 08 12 Electro mechanical Control Wiring Diagram ...
Page 22: ...22 Fig 35 48LC 08 12 RTU Open Control Wiring Diagram ...
Page 23: ...23 Fig 36 48LC 08 12 SystemVu Control Wiring Diagram ...
Page 25: ...25 Fig 38 48LC 08 12 Typical Power Wiring Diagram SystemVu Control 208 230 v Unit Shown ...
Page 61: ......