Carrier PrimeLINE 69NT40-561-200, Operation And Service Manual

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T-362 7–18
12. Remove the condenser fan, and connect the fan motor wiring to the fan motor.
13. Place the condenser fan on the shaft facing the correct direction. Adjust the fan to the correct position,
37mm (1.5”) from the fan shroud, see Figure 7.7 .
14. Use Loctite “H” on the fan set screws, and tighten.
15. Refit the left and right infill panels.
16. Refit the condenser fan grille, ensuring the grille is properly centered around condenser fan.
7.13 Water-Cooled Condenser Cleaning
The water-cooled condenser is of the shell and coil type with water circulating through the cupro-nickel coil. The
refrigerant vapor is admitted to the shell side and is condensed on the outer surface of the coil. Rust, scale and
slime on the water-cooling surfaces inside of the coil interfere with the transfer of heat, reduce system capacity,
cause higher head pressures and increase the load on the system.
By checking the leaving water temperature and the actual condensing temperature, it can be determined if the
condenser coil is becoming dirty. A larger than normal difference between leaving condensing water temperature
and actual condensing temperature, coupled with a small difference in temperature of entering and leaving
condensing water, is an indication of a dirty condensing coil.
If the water-cooled condenser is dirty, it may be cleaned and de-scaled.
7.13.1 Cleaning Supplies Needed
• Oakite Aluminum Cleaner® 164, available as a powder in 20 kg (44 lb) pails and 205 kg (450 lb) drums.
• Oakite Composition No. 32, available as a liquid in cases, each containing 3.785 liters (4 U.S. gallon) bottles
and also in carboys of 52.6 kg (116 lbs) net.
• Fresh clean water.
• Acid proof pump and containers or bottles with rubber hose.
NOTE
When Oakite Compound No. 32 is used for the first time, the local Oakite technical service
representative should be called in for suggestions in planning the procedure. The representative will
advise the reader on how to do the work with a minimum dismantling of equipment: how to estimate the
time and amount of compound required; how to prepare the solution; how to control and conclude the
de-scaling operation by rinsing and neutralizing equipment before putting it back into service. The
representative’s knowledge of metals, types of scale, water conditions and de-scaling techniques will
be highly useful.
7.13.2 Cleaning Procedure Summary
1. Turn the unit off and disconnect main power.
2. Disconnect the water pressure switch tubing by loosening the two flare nuts. Install a 1/4 inch flare cap on
the water-cooled condenser inlet tube (replaces tubing flare nut). De-scale tubing if necessary.
3. Drain water from the condenser tubing circuit.
4. Clean the water tubes with Oakite Aluminum Cleaner® 164 to remove mud and slime.
5. Flush.
6. De-scale the water tubes with Oakite No. 32 to remove scale.
7. Flush.
8. Neutralize.
9. Flush.
10. Put the unit back in service under normal load and check head (discharge) pressure.
7.13.3 Cleaning Procedure Detailed
1. Drain and flush the water circuit of the condenser coil. If scale on the tube inner surfaces is accompanied by
slime, a thorough cleaning is necessary before de-scaling process can be accomplished.