Carrier 48KHA - Manual (Page 9)

Unit Preparation
STARTUP
A WARNING
Failure to observe the following warnings could result
in serious personal injury;
1
2 .
3.
4.
Follow recognized safety practices and wear protective
goggles when checking or servicing refrigerant system.
Do not operate compressor or provide any electric
power to unit unless compressor terminal cover is in
place and secured.
Do not remove compressor terminal cover until all elec­
trical sources have been disconnected.
Relieve all pressure from system before touching or dis­
turbing anything inside terminal box if a refrigerant
leak is suspected around compressor terminals.
5. Never attempt to repair a soldered connection while
refrigerant system is under pressure.
6. Do not use a torch to remove any component. System
contains oil and refrigerant under pressure. To remove
a component, wear protective goggles and proceed as
follows:
a. Shut off gas supply first, and then electrical power
to unit.
b. Relieve all pressure from system.
c. Use tubing cutter to cut tubing that connects com­
ponent, and remove component from unit.
d. Carefully unsweat remaining tubing stubs when
necessary. Oil can ignite when exposed to torch
flame.
PRE-START-UP PROCEDURES-Proceed as follows to
inspect and prepare unit for initial start-up:
c. Maike sure air filter(s) is in place.
d. Make sure condensate dredn pan is filled with water
to ensure proper drainage.
e. Make sure 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.
A WARNING
Never attempt to repair a soldered connection while
refrigerant system is under pressure. Severe bodily
injury may result. Always wear protective goggles
when servicing the refrigerant system.
3.
1. Locate leak and ensure that refrigerant system pres­
sure has been relieved.
2. Repair leak following accepted practices.
NOTE; Install a filter drier whenever system has been
opened for repair.
3. Add a small cheu-ge of R-22 refrigerant vapor to system
and leEik-test unit.
4. Evacuate refrigerant system if additioned leaks are not
found.
5. Charge unit with R-22 refrigerant, using a volumetric-
charging cylinder, such as Dial-a-Charge, or accurate
scale. Refer to unit rating plate for required charge. Be
sure to add extra refrigerant to compensate for interned
volume of filter drier.
NOTE: See Cooling Section Start-Up and Adjustments—
Checking and Adjusting Refrigerant Charge.
Remove edl access panels.
Read and follow instructions on all WARNING, CAU­
TION and INFORMATION labels attached to or Heating Section Start-Up and Adjustments
shipped with the unit._______________________________________________________________________ _
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 connections
and on unit base. The presence of oil generally indi­
cates a refrigerant leeik. Leak-test all refrigerant
tubing connections using electronic leak detector,
halide torch or liquid soap solution. If refrigerant
leak is detected, see Refrigerant Leaks in next
section.
A CAUTION
Complete required procedures given in Unit Prepara­
tion section before starting unit.
c. Inspect all field- and factory-wiring connections. Be
sure connections are completed and tight.
d. Inspect coil fins. If damaged during shipping and
handling, carefully straighten fins with a fin comb.
A WARNING
Do not purge gas supply into combustion chamber. Do
not use a match or other open flame to check for gas
leaks. Failure to adhere to this warning may cause an
explosion.
4. Verify the following conditions:
a. Meike sure gas supply has been purged, and all gas
piping has been checked for leaks.
b. Make sure outdoor fan blade is correctly positioned
in fan orifice. Blades should clear fan motor by no
more than % inch.
Do not jumper any safety devices when operating unit.
Ensure that burner orifices are properly aligned. Unstable
operation may occur when the burner orifices in the mani­
fold are misedigned. To ensure correct burner orifice edign-
ment, check orifice angle with a machinist’s protractor or
other suitable device. The orifice angle must be from hori­
zontal to 3 degrees down, as measured from unit base.
Follow instructions on heating section operation label
(located in unit near the gas valve) or in Owner’s Manual, to
start the heating section.
CHECKING HEATING CONTROL OPERATION-Start
and check unit for proper heating control operation as
follows:
Place room thermostat selector switch in HEAT position
and fan switch in AUTO, position. Set heating temperature
control of thermostat above room temperature. Observe
that after built-in time delays, the pilot automatically
lights, burners light and blower motor starts. Observe that
burners and pilot are extinguished, and that after a built-in
delay, blower motor stops when heating control setting of
thermostat is satisfied.