Johnson Controls PC090 THRU 240 dimensions Defrost Operation, Fan Orientation, Control Box End

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430645-YIM-D-0610

Defrost Operation

The defrost control board (DC) utilizes a time/temperature defrost scheme. The DC repeats normal heating run cycles, which must be completed, until one of the following conditions is met and the DC enters defrost mode:

1.The DC satisfies its accumulated minimum run time. This is factory set at 60 minutes, but is field adjustable to 30, 60 or 90 minutes.

2.The defrost switch(es) is closed. This normally open switch is set to close at 28° F (+/-3°).

When the DC enters defrost mode, its on-board defrost relays are powered. This energizes the reversing valve solenoid, de- energizes the condenser fan motors and energizes the unit's optional electric heater. The DC remains in defrost mode until either of the following two conditions are met:

1.Both of the liquid line thermostats are open. Each is set to open at 55 degrees (+/- 3).

2.The maximum defrost run time of 10 minutes is met.

The DC also contains a set of test pins. Placing a jumper across these pins will result in the following actions:

If the ASCD timer is active, it is now bypassed, allowing the compressor to run.

If the DC is in a lockout condition, the lockout is reset.

If the compressor is running, the DC is forced into defrost mode. The control will remain in defrost mode as long as the jumper is in place. When the jumper is removed, the control will terminate defrost mode.

Table 10: PC090 thru 240 Unit Control Board Flash Codes

NOTE: The DC has two flash codes that only initiate if the jumper between the two pressure switch terminals is removed or broken.

Blower Operation

After completing the specified time for fan on-delay, UCB closes the coil of relay BR1.

Relay BR1 sends a 24V signal to G1 of terminal block TB2. It may be used to control operation of an indoor blower.

The UCB disables the signal to BR1 after completing the fan off-delay period.

 

Rear

Rear

2

2

4

1

1

3

 

Front

Front

Figure 9: Fan Orientation, Control Box End

 

 

GREEN

RED

RED

RED

RED

FLASH CODE

DESCRIPTION

LED

LED

LED

LED

LED

 

 

16

8

4

2

1

 

 

 

 

 

 

 

On Steady

This is a Control Failure

-

-

-

-

-

1 Flash

Not Applicable

-

-

-

-

-

2 Flashes

Control waiting ASCD1

Flashing

Off

Off

On

Off

3 Flashes

HPS1 Compressor Lockout

Off

Off

Off

On

On

4 Flashes

Not Applicable

-

-

-

-

-

5 Flashes

LPS1 Compressor Lockout

Off

Off

On

Off

On

6 Flashes

Not Applicable

-

-

-

-

-

7 Flashes

FS1 Compressor Lockout2

Off

Off

On

On

On

8 Flashes

Not Applicable

-

-

-

-

-

10 Flashes

Compressors Locked Out on Low Outdoor Air Temperature1

Flashing

On

Off

On

Off

12 Flashes

Unit Locked Out due to Fan Overload Switch Failure

Off

On

On

Off

Off

13 Flashes

Compressor Held Off due to Low Voltage1

Flashing

On

On

Off

On

14 Flashes

EEPROM Storage Failure

Off

On

On

On

Off

OFF

No Power or Control Failure

Off

Off

Off

Off

Off

1.Non-alarm condition.

2.Freeze - stat not applicable.

Johnson Controls Unitary Products

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Contents 410A General NomenclatureRenewal Parts Safety ConsiderationsAgency Approvals InspectionPC090 240 and PD180 240 Physical Data Physical DataInstallation LimitationsLocation Shipping Operating Corner Weights & Center of GravityClearances RiggingMinimum Clearances Clearance Description Distance in Inches Control Wiring Power WiringPhasing CompressorsFLA Electrical DataTake Adequate Precautions Refrigerant MainsLine Sizing Start Installation Thermostat Single Stage Cooling TWO Stage Heating NC120 240 Liquid Line Solenoid Wiring YIM-D-0610 Model Model Start-Up Piping And Electrical ConnectionsCrankcase Heaters Operation Sequence of OperationCooling Sequence Of Operation Dual Stage Heat Pump 4 pipe PD180-240 Dual Stage Heat Pump PC120-240Heating Sequence of Operation Fan Orientation, Control Box End Defrost OperationUnit Control Board PD180 thru 240 Unit Control Board Flash CodesUnit Control Board Option Setup TroubleshootingOption Byte Setup Normal MaintenanceCooling Troubleshooting Guide If none of the above correct the error, replace the UCB Johnson Controls Unitary Products Cooling Charging Curves Cooling Charging Curves PC240 Typical PC090 Heat Pump Wiring Diagram Typical Wiring DiagramsTypical PC120 Heat Pump Wiring Diagram Typical PC180 240 Heat Pump Wiring Diagram Johnson Controls Unitary Products York Drive Norman, OK

PC090 THRU 240, PD 180 THRU 240 specifications

Johnson Controls has long been a leader in the HVAC and building efficiency industry, and the Johnson Controls PC090 THRU 240 and PD 180 THRU 240 series of commercial rooftop units exemplify their commitment to innovation and energy efficiency. These units are designed to provide optimal performance for a wide range of commercial applications, ensuring comfortable indoor climates while maintaining energy savings.

One of the standout features of the Johnson Controls PC and PD series is their advanced cooling and heating capabilities. Both series can operate efficiently across a varied range of capacities, typically from 90,000 to 240,000 BTU/h for the PC series and 180,000 to 240,000 BTU/h for the PD series. This versatility allows users to select the most appropriate unit size for their specific needs, optimizing performance without wasting energy.

The technology behind these rooftop units includes advanced inverter-driven compressors that enable variable-speed operation. This feature allows for precise temperature control, resulting in enhanced comfort and reduced energy usage. The units also integrate smart controls that enable easy monitoring and management, ensuring that the HVAC system can adapt to changes in occupancy or external weather conditions.

Another notable characteristic of the Johnson Controls rooftop units is their robust construction and reliability. Designed for outdoor use, these units can withstand harsh weather conditions while maintaining operational efficiency. They are equipped with corrosion-resistant materials and protective enclosures to prolong the life of the equipment.

The units are also engineered with eco-friendliness in mind, utilizing refrigerants with low global warming potential to minimize their environmental impact. Furthermore, their energy-efficient designs often qualify for various energy incentives, providing businesses an additional return on investment.

Ease of installation and maintenance is another hallmark of the PC and PD series. With a modular design, these units can be easily transported and installed. Maintenance tasks are simplified, allowing facility management teams to perform regular service checks efficiently and effectively.

Overall, the Johnson Controls PC090 THRU 240 and PD 180 THRU 240 series stand out in the commercial HVAC market due to their flexibility, advanced technology, and dedication to energy efficiency and environmental responsibility. These units not only meet modern energy codes but also contribute to a sustainable future with their innovative features and reliable performance.