Kelvinator R-404A Installation Manual Download

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COMPRESSOR INSTALLATION & MAINTENANCE / DIAGNOSTICS

MAINTENANCE & REPAIR

HOLD DOWN BOLTS

All models with Copeland compressors have hold
down bolts. The compressor has a metal hold down
band strapping it tightly to the cabinet body. This band
should be removed and discarded upon installation. If
compressor does not float freely, keep backing off all of
the retaining nuts until it does.

CHECKING COMPRESSOR THAT WON’T
START ON CORD CONNECTED CABINETS

1. Check that the supply plug is in wall outlet and that

outlet has the proper voltage.

2. Check that the cabinet thermostat is on a numerical

setting.

If items 1 & 2 are OK:

3. Pull condensing unit out of the cabinet and remove

compressor terminal cover. Check proper voltage at
terminals.

TO CHANGE THE COMPRESSOR:

1. Disconnect the power supply to the cabinet.

2. Disconnect power supply leads at the compressor.

3. Disconnect the wires to the relay and capacitors.

4. Remove the relay and starting capacitor and install

on the new compressor.

5. Remove the defective compressor from the

condensing unit base.

6. Set the new compressor in place.

7. Reconnect the relay and capacitor wires.

8. Reconnect the power supply lead.

9. Leak test, evacuate, and weigh in charge.

CHANGING DRIER

If flare connected, make sure flares and faces of
fittings on new drier are clean and in good condition
before installing new drier.
Cut tubing only with tube cutters, not hacksaw’s, to
avoid metal filings from entering the system. Driers
must be replaced any time you enter the system,
except when you are obtaining operating pressures.

SERVICE VALVES

The compressors on some cabinets have service
valves for measuring suction and discharge pressures.
Two types are used. The first type is connected directly
to the compressor body or shell and back seats to
connect gauges to the access port. The second
(Schrader type) is on the end of a process tube and
requires a gauge or charging line with a depressing pin
to open valve when the connection is made.

CAUTION

This type valve should be tightly capped except when
making the gauge connection.

TO CHECK FOR OPEN WINDINGS

Use a multimeter. Measure ohms between “C” and “R”
and between “C” and “S”.
If windings are OK, multimeter will show a resistance
reading between terminals.
If there is no reading, the compressor, winding or
windings are open and the compressor should be
replaced.

TO CHECK FOR GROUNDED COMPRESSOR

Use multimeter. Touch probe from each terminal to an
unpainted surface of compressor body. If there is no
ground, there will be no change of the meter.

WARNING: Be Careful Not to Touch

Uninsulated Parts of the Meter Probes.

A reading indicates a ground and the compressor
should be replaced.

If there is voltage at the compressor terminals and the
compressor tries, but does not run, check voltage at the
compressor terminals while attempting to start the
compressor. If the voltage at the compressor terminal is
below 90% of the nameplate voltage, it is possible the
motor may not have developed sufficient torque to start.
Check to determine if:

A. Wire sizes are adequate.

B. Electrical connections are loose.

C. The circuit is overloaded.

D. The power supply is adequate.

A defective relay or capacitor may prevent the
compressor starting.

TO CHECK OUT THE RELAY

1. Disconnect the cabinet from the power supply.

2. Remove the wires from the relay.

3. Touch probes to the terminals. Meter should show

infinity if closed.

4. Touch probes to the terminals of coil. The meter

should show a resistance reading.