Carrier 69NT40-511-1 Capacitor analyzer, To Replace Condenser Coil, Partlow Recording Thermometer

WARNING

With power OFF discharge the capacitor and disconnect the circuit wiring.

c. Checking the capacitor

If the capacitor is suspected of malfunction, you may choose to simply replace it. Direct replacement requires a capacitor of the same value. Two methods for checking capacitor function are:

1.Volt-ohmmeter set on RX 10,000 ohms. Connect ohmmeter leads across the capacitor terminals and observe the meter needle. If the capacitor is good, the needle will make a rapid swing toward zero resistance and then gradually swing back toward a very high resistance reading.

If the capacitor has failed open, the ohmmeter needle will not move when the meter probes touch the terminals. If the capacitor is shorted, the needle will swing to zero resistance position and stay there.

2.Capacitor analyzer

The function of the analyzer is to read the microfarad value of a capacitor and to detect insulation breakdown under load conditions. The important advantages of a analyzer are its ability to locate capacitors that have failed to hold their microfarad ratings, or those that are breaking down internally during operation. It is also useful in identifying capacitors when their microfarad rating marks have become unreadable.

6.17 CONDENSER COIL

The condenser consists of a series of parallel copper tubes expanded into copper fins. The condenser coil must be cleaned with fresh water or steam so the air flow is not restricted. Fan rotation is counterclockwise when viewed from shaft end of motor.

WARNING

Do not open the condenser fan grille before turning power OFF and disconnecting power plug.

To Replace Condenser Coil:

a.Remove the refrigerant charge per section 6.3.

b.Remove the condenser coil guard.

c.Unsolder discharge line and remove the line to the receiver or water-cooled condenser (if so equipped).

d.Remove coil mounting hardware and remove the coil.

e.Install replacement coil and solder connections.

f.Leak-check the coil per section 6.4. Evacuate the unit per section 6.5, then charge the unit with refrigerant per section 6.6.1.

6.18 CONDENSER FAN AND MOTOR ASSEMBLY

WARNING

Do not open condenser fan grille before turning power OFF and disconnecting power plug.

The condenser fan rotates counter-clockwise (viewed from front of unit), pulls air through the the condenser coil, and discharges horizontally through the front of the unit. To replace motor assembly:

a.Open condenser fan screen guard.

b.Loosen two square head set screws on fan. (Thread sealer has been applied to set screws at installation.) Disconnect wiring from motor junction box.

CAUTION

Take necessary steps (place plywood over coil or use sling on motor) to prevent motor from falling into condenser coil.

c.Remove motor mounting hardware and replace the motor. It is recommended that new locknuts be used when replacing motor. Connect wiring per wiring diagram.

d.Install fan loosely on motor shaft (hub side in). DO NOT USE FORCE. If necessary, tap the hub only, not the hub nuts or bolts. Install venturi. Apply “Loctite H” to fan set screws. Adjust fan within venturi so that the outer edge of the fan projects 3.2 to 6.4 mm (3/16” ¦1/16”) back from edge of the venturi. Spin fan by hand to check clearance.

e.Close and secure condenser fan screen guard.

f.Apply power to unit and check fan rotation. If fan motor rotates backward, reverse wire numbers 5 and 8.

6.19 PARTLOW RECORDING THERMOMETER

NOTE

The Controller/DataCORDER return air probe is located adjacent to the Partlow bulb, and can be used to calibrate the chart recorder.

a. Instruments for Checking Bulb Temperature

The recording thermometer may be optionally equipped with one or two Simpson accessories (#344 units), each consisting of a thermistor probe and receptacle

T-268-07 6-18