Johnson Controls PD 180 THRU 240, PC090 THRU 240 dimensions Heating Sequence of Operation

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430645-YIM-D-0610

• Contactor M4 controls outdoor fans ODFAN3 & 4.

If the initial call for cooling requires both stages (Y1 and Y2), the UCB will delay the second stage by 30 seconds to avoid an excessive power inrush.

When the call for cooling (Y2) is satisfied, the UCB disables the signal to RY2 and M2 as long as the specified minimum run time (ASCD) has elapsed.

When the call for cooling (Y1) is satisfied, the UCB disables the signal to RY1 and M1 as long as the specified minimum run time (ASCD) has elapsed.

Low Ambient Cooling

These units are factory equipped with low ambient switches that work through the Simplicity control board to operate the compressors and condenser fans normally to 40ºF ambient temperature. The Electronic Low Ambient Controller 2LA04703000 Accessory is designed to assure safe operation through condenser head pressure regulation down to 0ºF ambient temperature.

Low Ambient Control Operation

•A call for cooling closes contactor M3 which energizes all condenser fans. The Low Ambient Control starts all fans at full speed then adjusts according to the liquid line temperature.

Refer to the appropriate 2LA low ambient kit instructions for additional detail on the factory or field installed low ambient kit and its operation.

Heating Sequence of Operation

General

Heat pump models are to be matched with air handlers of equivalent tonnage ratings. Twinning of heat pumps and air handlers is not recommended.

A two stage thermostat is required to operate the heat pump in heating mode.

All reversing valves are de-energized during normal heating mode. They are energized only during cooling and defrost modes.

The heat pump operates all compressors during a first stage call for heating unless locked out by the Unit Control Board (UCB).

First Stage Heating Operation

When the thermostat calls for first stage heating (W1):

•The Simplicity control board (UCB) goes into a five minute ASCD timer delay.

•When the ASCD time delay is satisfied, the UCB closes its internal compressor relay contact, thus energizing the contacts of relay RY1 and contactor M1.

•Relay RY1 has two functions: 1) control the operation of crankcase heater CCH1, and 2) control the 24V output signal to S1 on terminal block TB2.

•Contactor M1 controls compressor COMPR1.

•Relay RY3 (RY2 for PC090 model) toggles the 24V signal from the "O" terminal of DC to the "Y" terminal assuring the reversing valve cannot be energized except during defrost.

•Concurrently, a 24V signal is sent to one of the "CFAN" terminals of DC. The output signal from the remaining "CFAN" terminal closes the coil of contactor M3.

•Contactor M3 controls outdoor fans ODFAN1 & 2 (all models) and ODFAN3 & 4 (PC180-240).

(PC120-240; PD180-240 models)

•After a two second delay, the UCB energizes the contacts of relay RY2 and contactor M2.

•Relay RY2 has two functions: 1) control the operation of crankcase heater CCH2, and 2) control the 24V output signal to S2 on terminal block TB2.

•Contactor M2 controls compressor COMPR2.

(PD180-240 models only)

•Concurrently, a 24V signal is sent to one of the "CFAN" terminals of defrost control board DC2. The output signal from the remaining "CFAN" terminal closes the coil of contactor M4.

• Contactor M4 controls outdoor fans ODFAN3 & 4.

Second Stage Heating Operation

When the thermostat calls for second stage heating (W2):

•A 24V signal passes through UCB sending an input signal to the "W" terminal of DC. This signal passes through DC as an output signal to the "66" terminal of TB2 to be used as a control signal for first stage electric heat.

Emergency Heating Operation

When the thermostat calls for emergency heating (EMER):

•The UCB de-energizes all compressor relays and contactors.

•A 24V signal passes through UCB sending an input signal to the "W" terminal of DC. This signal passes through DC as an output signal to the "66" terminal of TB2 to be used as a control signal for first stage electric heat.

•The normally closed contacts of M1-AUX and M2-AUX

(PC120-240; PD180-240 models only) send a 24V output signal to the "60" terminal of TB2 to be used as a control signal for second stage electric heat.

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Johnson Controls Unitary Products

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Contents 410A Nomenclature GeneralSafety Considerations Renewal PartsAgency Approvals InspectionPhysical Data PC090 240 and PD180 240 Physical DataLocation InstallationLimitations Corner Weights & Center of Gravity Shipping OperatingMinimum Clearances Clearance Description Distance in Inches ClearancesRigging Power Wiring Control WiringPhasing CompressorsElectrical Data FLALine Sizing Take Adequate PrecautionsRefrigerant Mains Start Installation Thermostat Single Stage Cooling TWO Stage Heating NC120 240 Liquid Line Solenoid Wiring YIM-D-0610 Model Model Crankcase Heaters Start-UpPiping And Electrical Connections Cooling Sequence Of Operation OperationSequence of Operation Dual Stage Heat Pump PC120-240 Dual Stage Heat Pump 4 pipe PD180-240Heating Sequence of Operation Defrost Operation Fan Orientation, Control Box EndPD180 thru 240 Unit Control Board Flash Codes Unit Control BoardTroubleshooting Unit Control Board Option SetupOption 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 Wiring Diagrams Typical PC090 Heat Pump Wiring DiagramTypical 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.
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