Table of Contents
Advertisement
The cable should be made in the following manner:
Cut the control cable to the desired length. When cutting
make sure ends are cut straight, not diagonally. Next, use
an RJ-11 connector crimping tool.
Use the stripper section of the tool to remove the outer insu-
lation of the cable. Be careful not to remove or break the
colored insulation of the inner conductors. Repeat on oppo-
site end.
Insert the prepared cable into the RJ-11 plug. When insert-
ing cable you MUST be sure that the black wire is on your
left as you look at the top of the plug. See FIG. 5. Insert the
RJ-11 plug into the tool and squeeze to the stop. Repeat
the procedure for other end.
FIG. 5
The finished cable can be tested with a 3107127.007 com-
fort control cable tester. See Section B16 for more informa-
tion on the testing of the cable.
3. COMPRESSOR
The compressor motor can be electrically checked. Be
sure to disconnect all power and turn all switches to the
"OFF" position, before starting to do the tests.
Remove the terminal cover from the compres-
sor and disconnect the three leads connected
to the terminals. Make note of the positions
so the wires can be replaced correctly.
Use an ohmmeter to check for continuity through the over-
load device. If no continuity is found and the compressor is
hot, allow 15 to 20 minutes for the compressor to cool. If a
repeat of the test shows the overload to be open, it is defec-
tive and requires replacement.
Continuity should exist between all three terminals of the
compressor. If there is no continuity the compressor wind-
ings are open and the compressor is defective.
Scrape the compressor casing to bare metal and check
continuity from each terminal to the casing. If continuity is
found to the casing on any of the terminals, the compressor
is shorted and it is defective.
4. CAPACITORS
Duo-Therm Air Conditioners and Heat Pumps use three dif-
ferent capacitors: 1) compressor run capacitor 2) compres-
sor start capacitor and 3) fan/blower capacitor. On some
units the compressor run and fan/blower capacitor are in
the same case.
The compressor run and fan/blower capacitor are housed in
a steel or aluminum case. The start capacitor is in a bake-
alite or plastic shell. Some have a 15,000 ohm bleeder
resistor across the terminals.
The power must be turned "OFF" and capacitors must be
discharged before making the test. Use an AC voltmeter
(set to the highest scale) or a 15,000 ohm 2 watt resistor to
bleed away any charge left in the capacitor.
Remove the wires from the terminals and inspect the cas-
ing. If it is bulged, cracked or split, the capacitor is defec-
tive.
Use an analog voltmeter (dial or hand reading indicator) to
test the capacitor after it has been discharged. Set the
ohmmeter to mid-range and check for resistance to the case.
Any resistance to the case from the terminals indicates it is
defective and it needs to be replaced.
Set the ohmmeter to the highest scale and read across the
terminals on the capacitor. The ohmmeter should swing
towards zero and slowly move back towards infinity. Re-
verse the leads and repeat the test. If the ohmmeter stays
on infinity, it is open and needs to be replaced. If very little
meter movement is noticed, switch the meter to a lower
scale and repeat test.
The capacitors with the 15,000 ohm resistor should be
checked on the 1,000 ohm scale. The ohmmeter should
swing below 15,000 ohms and return. Reverse leads and
repeat test. If the capacitor does not act as described it is
defective and needs to be replaced.
5. MOTORS
To determine if a motor is good, test the windings with an
ohmmeter. Disconnect the power supply, and turn all the
switches to the "OFF" position. Disconnect the motor leads
(on some models disconnect the 6 pin plug from the electri-
cal box). The motor should show continuity between all
leads and the white wire. Infinity or no continuity indicates
the winding is open and the motor is defective.
Check for continuity between the motor frame and each lead.
If a continuity reading is present to any lead, the motor is
shorted and defective.
The motor can be tested with an ammeter to determine if
the operation is within the rating (±10%) listed on the model
plate. Many times the motor windings will check good, but
bad bearings or capacitor may be found in an ampere test.
6. REMOTE SENSOR
The remote sensor is the temperature sensor that allows
the unit for a zone to cycle "ON" and "OFF" by temperature.
A remote sensor is used for each unit or zone. A remote
sensor is usually optional for zone 1; but, in some applica-
tions the Comfort Control Center is located for convenience
of access and the remote sensor placed for temperature
control.
3
Hide quick links:
Advertisement
Table of Contents
Troubleshooting
