Carrier 38AUQ 16 Series, Installation, Start-Up And Service Instructions Manual

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Table 11 – CADM Troubleshooting
Miswired Module Indication Recommended Troubleshooting Action
Green LED is not on,
module does not power up
Determine if both R and C module terminals are connected. Verify voltage in
present at module’s R and C terminals.
NOTE: The CADM requires a constant nominal 24VAC power supply. The
wiring to the module’s R and C terminals must be directly from the control
transformer. The module cannot receive its power from another device that will
interrupt the 24VAC power supply. See Figs. 18 and 19, the 38AUQ Wiring
Diagram.
Green LED Intermittent,
module powers up only
when compressor runs
Determine if R and Y terminals are wired in reverse. Verify module’s R and C
terminals have a constant source. See “ NOTE ” above for details on R and C
wiring.
TRIP LED is on but system
and compressor check OK
Verify Y terminal is wired properly per the 38AUQ wiring diagram (see Figs. 18
and 19). Verify voltage at contactor coil falls below 0.5VAC when off. Verify
24VAQC is present across Y and C when thermostat demand signal is present.
If not, R and C are reverse wired.
TRIP LED and ALERT LED
flashing together
Verify R and C terminals are supplied with 19-28VAC.
ALERT Flash Code 3
(Compressor Short Cycling)
displayed incorrectly
Verify Y terminal is connected to 24VAC at contactor coil. Verify voltage at
contactor coil falls below 0.5VAC when off.
ALERT Flash Code 5 or 6
(Open Circuit, Missing Phase)
displayed incorrectly
Check that compressor T1 and T3 wires are through module’s current sensing
holes. Verify Y terminal is connected to 24VAC at contactor coil. Verify voltage
at contactor coil falls below 0.5VAC when off.
Alert Flash Code *
(Welded Contactor)
displayed incorrectly
Determine if module’s Y terminal is connected. Verify Y terminal is connected to
24VAC at contactor coil. Verify 24VAC is present across Y and C when
thermostat demand signal is present. If not, R and C are reverse wired. Verify
voltage at contactor coil falls below 0.5VAC when off.
Outdoor Fans
Each fan is supported by a formed-wire mount bolted to
the fan deck and covered with a wire guard. Fan motors
have permanently lubricated bearings.
1. Shut off unit power supply. Install lockout tag.
2. Remove outdoor fan assembly (grille, motor, and fan).
3. Loosen fan hub setscrews.
4. Adjust fan height as shown in Fig. 31.
5. Tighten setscrews to 84 in--lbs (949 N--cm).
6. Replace outdoor fan assembly.
3.6 mm +0/0/-0.8
C10103
Fig. 31 -- Outdoor Fan Blade Position
Lubrication
Fan Motors —
The fan motors have sealed bearings. No provisions are
made for lubrication.
Compressor —
The compressor has its own oil supply. Loss of oil due to
a leak in the system should be the only reason for adding
oil after the system has been in operation.
Outdoor Coil Maintenance and Cleaning
Recommendation
Routine cleaning of coil surfaces is essential to maintain
proper operation of the unit. Elimination of contamination
and removal of harmful residues will greatly increase the
life of the coil and extend the life of the unit. The
following maintenance and cleaning procedures are
recommended as part of the routine maintenance activities
to extend the life of the coil.
Remove Surface Loaded Fibers —
Surface loaded fibers or dirt should be removed with a
vacuum cleaner. If a vacuum cleaner is not available, a
soft non-metallic bristle brush may be used. In either case,
the tool should be applied in the direction of the fins. Coil
surfaces can be easily damaged (fin edges can be easily
bent over and damage the coating of a protected coil) if
the tool is applied across the fins.
NOTE
: Use of a water stream, such as a garden hose,
against a surface loaded coil will drive the fibers and dirt
into the coil. This will make cleaning efforts more
difficult. Surface loaded fibers must be completely
removed prior to using low velocity clean water rinse.
Periodic Clean Water Rinse —
A periodic clean water rinse is very beneficial for coils
that are applied in coastal or industrial environments.
However, it is very important that the water rinse is made
with very low velocity water stream to avoid damaging
the fin edges. Periodic cleaning as described below is
recommended.
38A
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