Carrier 48GH - Manual (Page 9)

3. Make following inspections;
a. Inspect for shipping and handling damages
such as broken lines, loose parts, disconnected
wires, etc.
b. Inspect for oil at all refrigerant tubing connec­
tions and on unit base. Detecting oil generally
indicates a refrigerant leak. Leak-test all
refrigerant tubing connections using elec­
tronic leak detector, halide torch, or liquid-
soap solution. If refrigerant leak is detected,
see REFRIGERANT LEAKS in next part
of this section.
c. Inspect all field- and factory-wiring connec­
tions. Be sure that connections are completed
and tight.
d. Inspect coil fins. If damaged during shipping
and handling, carefully straighten fins with
a fin comb.
WARNING; Do not purge gas supply
conibtistiou chamber. Do not use a match or
other open flame to check for ga.s leaks.
4. Verily the following conditions:
a. Make sure that gas supply has been purged,
and that all gas piping has been checked for
leaks.
b. Make sure that outdoor fan blade is correctly
positioned in fan orifice. Blades should clear
fan motor by no more than lj4 inch.
c. Make sure that air filter(s) is in place.
d. Make sure that condensate drain pan is filled
with water to ensure proper drainage.
e. Make sure that all tools and miscellaneous
loose parts have been removed.
5. Replace all access panels. Unit is now ready for
initial start-up.
REFRIGERANT LEAKS — Proceed as follows to
repair a refrigerant leak and to charge the unit;
WARNING: Never attempt to repair a soldered
cormeciion w'hik the refrigerant system is under
pressure. Severe bodily injury may result.
Always wear protective goggles when ser\dcing
the refrigerant system.
1. Locate leak and ensure that refrigerant system
pressure has been relieved.
2. Repair leak following aecepted practices.
NOTE: Install a filter-drier whenever system has
been opened for repair.
3. Add a small charge of R-22 refrigerant vapor to
system and leak-test unit.
4. Evacuate refrigerant system if additional leaks
are not found.
5. Charge unit with R-22 refrigerant, using a
volumetric-charging cylinder such as Dial-a-
Charge or accurate scale. Be/er to unit rating
plate for required charge. Be sure to add extra
refrigerant to compensate for internal volume of
filter-drier.
NOTE: See Cooling Section Start-Up and Adjust­
ments — CHECKING AND ADJUSTING RE­
FRIGERANT CHARGE for checking and adjust­
ing refrigerant charge.
Heating Section Start-Up and Adjustments
CAUTION: Complete required procedures
given in Unit Preparation section before startir^
unit.
Do not jumper any safety devices when operating
unit.
Ensure that burner orifices are properly aligned.
Unstable operation may occur when burner orifices
in manifold are misaligned. To ensure correct
burner orifiee alignment, check orifice angle with a
machinist’s protractor or other suitable device. The
orifice angle must be from horizontal to 3 degrees
down, as measured from unit base.
Follow instructions on heating section operation
label (located in unit near the gas valve) to start
heating seetion.
CHECKING HEATING CONTROL OPERA­
TION — Start and cheek unit for proper heating
control operation as follows:
Plaee room thermostat selector switch in HEAT
position and fan switch in AUTO, position. Set
heating temperature control of thermostat above
room temperture. Observe that after built-in time
delays, pilot automatically lights, burners light, and
blower motor starts. Observe that burners and pilot
go out, and that after a built-in delay blower motor
stops when heating control setting of thermostat is
satisfied.
GAS INPUT — Unit rating plate indieates 2 A.G.A-
certified gas inputs. When shipped from factory,
manifold has natural-gas burner orifices that deliver
minimum rated gas input. Optional field-installed
burner orifices are required to provide optional
maximum rated gas input. See Table 3.
When unit is being installed for operation at the
optional input, proceed as follows to install field-
supplied burner orifices:
1. Remove burner shield and burners.
2. Remove factory-supplied burner orifiees from
manifold and replace with field-supplied orifices.
3. Replace burners and burner shield.
4. Mark appropriate changes on unit rating plate.
CAUTION: These units are designed lo con­
sume rated, gas inputs using fixed orifices at
sp^ified
manifold pressures as shown in
Table 3. Do not redrilk orifices under any
drcxiinstances.