McQuay Incremental PDNS Series

Questions and Answers

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Robert WilsonAug 17, 2025
Why is my McQuay Air Conditioner not cooling enough?
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  Antonio FreemanAug 18, 2025
  Several factors could be responsible for insufficient cooling. If the air conditioner hasn't been run for a while, refrigerant might be absorbed in the compressor oil; allow about 5 minutes of continuous running to establish working pressures. Check for sufficient airflow through the condenser and evaporator, ensuring they are clean and free of obstructions. Confirm the condenser and evaporator blower motors are running at the correct speed and not slipping. Compare the heat load in the room to the equipment's capacity, recalculating if necessary. Finally, ensure all windows and doors in the room are closed.
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Jeffrey JohnsonAug 20, 2025
Why is my McQuay Air Conditioner not heating properly?
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  Adam AlexanderAug 20, 2025
  If there is insufficient or no heat, first check if steam or hot water is being applied; contact building management if necessary. Ensure there is power by checking fuses and circuit breakers. Inspect the pushbutton switch for faults or loose connections, replacing or tightening as needed. Verify the thermostat is set appropriately and is not faulty; adjust or replace as needed. Check for power output on the transformer secondary and replace if there is none. Finally, examine the valve for proper operation, and replace if inoperative.
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Gina CastanedaAug 23, 2025
Why does my McQuay Incremental PDNS Air Conditioner blowers run on COOL and compressor starts but stops after a short interval?
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  Matthew CollinsAug 23, 2025
  This issue might occur due to the overload device activating because the compressor motor is overloaded. Check the voltage supply and clean the condenser both inside and out. Inspect the outside face of the condenser to ensure condenser air isn't recirculating. If air splitters are missing, install them. Verify the condenser blower/fan is working correctly. Also, check the compressor for a short circuit. If the compressor is defective, consider shipping the cooling chassis to the nearest McQuay authorized warranty station.
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Timothy MillerAug 26, 2025
What to do if McQuay Air Conditioner blowers operate on COOL but compressor doesn’t start?
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  trevinokatherineAug 26, 2025
  Several factors can prevent the compressor from starting. First, ensure the thermostat isn't set too high; adjust it to a cooler setting. Check that the heat valve is closed, and the heat isn't on. Low voltage can also be a culprit, so check the power supply. Inspect and, if necessary, replace a faulty pushbutton switch or tighten any loose connections at the switch or compressor terminals. Defective wiring to the thermostat or compressor terminals should be replaced. Also, examine the compressor overload device for loose connections and tighten them. Replace a malfunctioning starting capacitor. If the compressor motor is defective, consider replacing the cooling chassis at the nearest McQuay authorized warranty station.
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James NguyenAug 27, 2025
What to do if my McQuay Incremental PDNS is too noisy?
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  William HortonAug 27, 2025
  Several factors can cause noise. Ensure the blower isn't rubbing against the enclosure; adjust its position or the motor bracket. If the blower motor bearings are dry, replace the motor. Tighten any loose blower hold-down nuts and ensure the blower assembly is aligned. If refrigerant is absorbed in the compressor oil after a shutdown, the noise should disappear after running the equipment for a while. Verify the equipment is properly installed and make necessary adjustments. Check the damper solenoid for proper adjustment and apply silicone oil or grease if it hums. Tighten any loose terminal box covers, electrical components, or sheet metal parts. Adjust vibrating copper tubing. In rare cases, harmonics may cause noise for no apparent reason.
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kim28Aug 30, 2025
What to do if my McQuay Incremental PDNS blowers won’t operate on COOL?
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  Meghan WrightAug 30, 2025
  If the blowers aren't operating on COOL, start by checking the power supply, including fuses and circuit breakers, and ensure the power is on. Blown fuses may indicate circuit overloading, a short circuit, or a grounded condition. Verify the voltage supply is within 10% of the data plate's specification. If the power supply is adequate, inspect the pushbutton switch for faults or loose connections; replace or tighten as needed.
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brian56Sep 1, 2025
Why does my McQuay Incremental PDNS Air Conditioner compressor starts and runs on COOL but blowers do not run?
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  robinsondarrylSep 1, 2025
  If the compressor runs but the blowers don't, the internally connected overload device may be activated due to a short circuit in the blower motor. Adjust the blower/fan wheel on the shaft or the blower motor mounting. Alternatively, rubbing windings or a lack of lubrication in the blower motor bearings could be the cause; adjust the blower wheel or motor, or replace the wheel.
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Christopher Savage PhDSep 4, 2025
Why does my McQuay Incremental PDNS Air Conditioner blowers run on COOL and compressor starts and runs, but compressor occasionally stops (on overload device)?
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  Richard TaylorSep 4, 2025
  The compressor might be stopping due to the overload device being triggered. This could be caused by low voltage from overloaded circuits or fluctuations in the local power system. Running a separate electric line to the equipment or consulting the local power company may resolve this. Another cause could be a partial short circuit in the compressor motor. If this is confirmed, ship the cooling chassis prepaid to the nearest McQuay authorized warranty station.
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Ricky BakerSep 7, 2025
What to do if my McQuay Air Conditioner gives electrical shock?
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  Ryan GregorySep 7, 2025
  If the equipment is giving an electrical shock, it indicates a grounded electrical circuit. You should eliminate the ground.
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Madison CobbSep 9, 2025
Why is my McQuay Incremental PDNS Air Conditioner giving “Sweating”?
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  David LiSep 9, 2025
  Sweating can occur due to several reasons. The condensate drain from the evaporator to the condenser might be plugged. Damaged insulating seals on the equipment could also be a factor. An evaporator blower motor not running at the correct speed or incorrectly positioned can also contribute to this issue. Check the voltage to ensure the motor is running at the correct speed, and adjust the blower's position as needed.