Refrigerant HFC-134a MUST NOT be mixed with air or oxygen and pressurized for leak testing. In general, this refrigerant should not be allowed to be present with high concentrations of air or oxygen above atmo- spheric pressures, because the mixture can undergo combustion.

REFRIGERANT TRACER Ð Use an environmentally ac- ceptable refrigerant as a tracer for leak test procedures.

TO PRESSURIZE WITH DRY NITROGEN Ð Another method of leak testing is to pressurize with nitrogen only and use a soap bubble solution or an ultrasonic leak detector to determine if leaks are present. This should only be done if all refrigerant has been evacuated from the vessel.

1.Connect a copper tube from the pressure regulator on the cylinder to the refrigerant charging valve. Never apply full cylinder pressure to the pressurizing line. Follow the listed sequence.

2.Open the charging valve fully.

3.Slowly open the cylinder regulating valve.

4.Observe the pressure gage on the chiller and close the regulating valve when the pressure reaches test level. Do not exceed 140 psi (965 kPa).

5.Close the charging valve on the chiller. Remove the cop- per tube if no longer required.

Repair the Leak, Retest, and Apply Standing Vacuum Test Ð After pressurizing the chiller, test for leaks with an electronic leak detector, soap bubble solution, or an ultrasonic leak detector. Bring the chiller back to at- mospheric pressure, repair any leaks found, and retest.

After retesting and ®nding no leaks, apply a standing vacuum test, and then dehydrate the chiller. Refer to the Standing Vacuum Test and Chiller Dehydration in the Before Initial Start-Up section, page 49.

Checking Guide Vane Linkage Ð Refer to Fig. 35.

If slack develops in the drive chain, eliminate backlash as follows:

1.With the chiller shut down (guide vanes closed), remove the chain guard, loosen the actuator holddown bolts, and remove the chain.

2.Loosen the vane sprocket set screw and rotate the sprocket wheel until the set screw clears the existing spotting hole.

3.With the set screw still loose, replace the chain, and move the vane actuator to the left until all the chain slack is taken up.

4.Tighten the actuator holddown bolts and retighten the set screw in the new position.

5.Realign the chain guard as required to clear the chain.

Contact Seal Maintenance (Refer to Fig. 36) Ð

During chiller operation, oil that lubricates the seal seeps through the space between the contact sleeve (Item 18) and the lock nut (Item 15). This oil slowly accumulates in an atmo- spheric oil chamber and is automatically returned to the sys- tem by a seal oil return pump.

Oil should never leak around the outer diameter of the contact sleeve (Item 18). If oil is found in this area, O-ring (Item 12) should be checked and replaced.

The oil passing through the shaft seal carries with it some absorbed refrigerant. As the oil reaches the atmosphere, the absorbed refrigerant is released from the oil as a vapor. For this reason, a detector will indicate the presence of a slight amount of refrigerant around the compressor shaft when- ever the chiller is running.

Fig. 35 Ð Electronic Vane Actuator Linkage

During shutdown, no refrigerant should be detected ex- cept for minute outgassing from residual oil in the seal area. There should be no oil seepage. If oil ¯ow or the presence of refrigerant is noted while the chiller is shut down, a seal defect is indicated. Arrange for a seal assembly inspection by a quali®ed serviceman to determine the cause of the leak- age and make the necessary repairs.

SEAL DISASSEMBLY (Fig. 36) Ð Contact seal disassem- bly and repair should be performed only by well quali®ed compressor maintenance personnel. These disassembly in- structions are included only as a convenient reference for the authorized serviceman.

For ease of disassembly, refer to Fig. 36 while following these instructions.

1.Remove refrigerant.

2.Remove compressor shaft coupling hub and coupling spacer (if any).

3.The snap ring (Item 16) used for seal assembly/disassembly is clipped over three screws (Item 41) on the windage baffle (Item 7). Remove the snap ring and put it aside for now.

4.Remove the screws holding the windage baffle and the shaft end labyrinth (Item 8).

5.Remove the contact sleeve key (Item 11).

6.Using a snap ring tool, install the snap ring (Item 16) in the groove on the end of the contact sleeve (Item 18), as shown in Fig. 36.

7.Remove the tubing between the coupling (Item 20) and the atmospheric oil chamber. Loosen the bolts (Item 6) holding the coupling guard mounting ring (Item 4) and the seal housing (Item 3). The spring contact sleeve (Item 17) will push the housing out until the snap ring (Item 16) contacts the seal housing (Item 3). To avoid binding, loosen the bolts in a circular pattern until the spring stops pushing out on the housing. Then, remove 2 bolts that are 180 degrees apart. Replace them with a 1/2-13 all-thread rod to support the housing while the rest of the bolts are removed.

8.Remove the rest of the bolts, and remove the seal housing.

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Carrier 17EX specifications Checking Guide Vane Linkage Ð Refer to Fig, Contact Seal Maintenance Refer to Ð

17EX specifications

The Carrier 17EX is recognized as an innovative air conditioning solution that combines efficiency with advanced technology. This model is designed to meet the increasing demands of residential and commercial cooling needs while maintaining environmental consciousness.

One of the standout features of the Carrier 17EX is its impressive Seasonal Energy Efficiency Ratio (SEER) rating. With a SEER rating that often exceeds 17, this unit ensures optimized energy consumption, significantly lowering operational costs for users. The incorporation of advanced compressor technology allows the system to adjust its cooling output based on the specific needs of the environment, thus providing both comfort and energy savings.

The Carrier 17EX utilizes a variable-speed inverter-driven compressor that enhances its performance and adaptability. This technology allows the air conditioning unit to operate at different speeds, intelligently adjusting to changing load conditions. As a result, the system runs more efficiently and quietly, providing a more consistent comfort level without the abrupt temperature swings associated with traditional units.

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For users concerned about indoor air quality, the Carrier 17EX includes advanced filtration systems designed to capture allergens and airborne particles. This feature is particularly beneficial for individuals with respiratory issues, ensuring that the air circulated within the space is clean and healthy.

Moreover, the Carrier 17EX is equipped with smart technology capabilities, allowing users to control their systems remotely through smartphones or other smart devices. This connectivity not only provides convenience but also empowers homeowners to optimize their energy use by adjusting settings on the fly, ensuring efficient operation even when they are away from home.

Overall, the Carrier 17EX stands out in the marketplace for its exceptional energy efficiency, advanced technology, and commitment to providing reliable and effective cooling solutions. Its combination of modern features makes it a preferred choice for those looking to enhance comfort while being mindful of energy consumption and environmental impact.