Carrier 50TCA04-A07 - Manual (Page 40)

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2. Set the Enthalpy potentiometer to A. The Free Cool
LED turns on. The actuator should drive to between
20 and 80% open.
3. Remove the 5.6 kilo--ohm resistor and jumper T to
T1. The actuator should drive fully open.
4. Remove the jumper across T and T1. The actuator
should drive fully closed.
5. Return EconoMi$er IV settings and wiring to normal
after completing troubleshooting.
EconoMi$er IV Troubleshooting Completion
This procedure is used to return the EconoMi$er IV to
operation. No troubleshooting or testing is done by
performing the following procedure.
1. Disconnect power at TR and TR1.
2. Set enthalpy potentiometer to previous setting.
3. Set DCV maximum position potentiometer to previ-
ous setting.
4. Set minimum position, DCV setpoint, and exhaust po-
tentiometers to previous settings.
5. Remove 620--ohm resistor from terminals SR and +.
6. Remove 1.2 kilo--ohm checkout resistor from termin-
als SO and +. If used, reconnect sensor from termin-
als SO and +.
7. Remove jumper from TR to N.
8. Remove jumper from TR to 1.
9. Remove 5.6 kilo--ohm resistor from T and T1. Recon-
nect wires at T and T1.
10. Remove jumper from P to P1. Reconnect device at P
and P1.
11. Apply power (24 vac) to terminals TR and TR1.
WIRING DIAGRAMS
See Fig. 65--66 for typical wiring diagrams.
PRE--START--UP
PERSONAL INJURY HAZARD
Failure to follow this warning could result in personal
injury or death.
1. Follow recognized safety practices and wear pro-
tective goggles when checking or servicing refri-
gerant system.
2. Do not operate compressor or provide any electric
power to unit unless compressor terminal cover is
in place and secured.
3. Do not remove compressor terminal cover until
all electrical sources are disconnected.
4. Relieve all pressure from system before touching
or disturbing anything inside terminal box if refri-
gerant leak is suspected around compressor ter-
minals.
5. Never attempt to repair soldered connection while
refrigerant system is under pressure.
6. Do not use torch to remove any component. Sys-
tem contains oil and refrigerant under pressure.
To remove a component, wear protective goggles
and proceed as follows:
a. Shut off electrical power to unit.
b. Recover refrigerant to relieve all pressure from
system using both high--pressure and low
pressure ports.
c. Cut component connection tubing with tubing
cutter and remove component from unit.
d. Carefully unsweat remaining tubing stubs
when necessary. Oil can ignite when exposed
to torch flame.
!
WARNING
Proceed as follows to inspect and prepare the unit for
initial start--up:
1. Remove all access panels.
2. Read and follow instructions on all WARNING,
CAUTION, and INFORMATION labels attached to,
or shipped with, unit.
3. Make the following inspections:
a. Inspect for shipping and handling damages such
as broken lines, loose parts, or 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 refri-
gerant tubing connections using electronic leak
detector, halide torch, or liquid--soap solution.
c. Inspect all field--wiring and factory--wiring con-
nections. Be sure that connections are completed
and tight. Be sure that wires are not in contact
with refrigerant tubing or sharp edges.
d. Inspect coil fins. If damaged during shipping and
handling, carefully straighten fins with a fin
comb.
50TC