Bard PH1224, PH1230 Start UP and Operation, Three Phase Scroll Compressor Start UP Information

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START UP AND OPERATION

THREE PHASE SCROLL COMPRESSOR START UP INFORMATION

Scroll compressors, like several other types of compressors, will only compress in one rotational direction. Direction of rotation is not an issue with single phase compressors since they will always start and run in the proper direction.

However, three phase compressors will rotate in either direction depending upon phasing of the power. Since there is a 50-50 chance of connecting power in such a way as to cause rotation in the reverse direction, verification of proper rotation must be made. Verification of proper rotation direction is made by observing that suction pressure drops and discharge pressure rises when the compressor is energized. Reverse rotation also results in an elevated sound level over that with correct rotation, as well as, substantially reduced current draw compared to tabulated values.

Verification of proper rotation must be made at the time the equipment is put into service. If improper rotation is corrected at this time there will be no negative impact on the durability of the compressor. However, reverse operation for over one hour may have a negative impact on the bearing due to oil pump out.

NOTE: If compressor is allowed to run in reverse rotation for several minutes the compressor’s internal protector will trip.

All three phase ZR*3 compressors are wired identically internally. As a result, once the correct phasing is determined for a specific system or installation, connecting properly phased power leads to the same Fusite terminals should maintain proper rotation direction.

The direction of rotation of the motor may be changed by reversing any two line connections to the unit.

SEQUENCE OF OPERATION

COOLING – Circuit R-Y makes at thermostat pulling in compressor contactor starting the compressor and outdoor motor. The G (indoor motor) circuit is automatically completed on any call for cooling operation, or can be energized by manual fan switch on subbase for constant air circulation.

HEATING – A 24V solenoid coil on reversing valve controls heating cycle operation. Two thermostat options, one allowing “AUTO” changeover from cycle to cycle and the other constantly energizing solenoid coil during heating season and thus eliminating pressure equalization noise except during defrost, are to be used. On “AUTO” option, a circuit is completed from R-W1 and R-Y on each heating “On” cycle energizing reversing valve solenoid and pulling in compressor contactor starting compressor and outdoor motor. R-G also make starting indoor blower motor. Heat pump heating cycle now in operation. The second energizes

the reversing valve solenoid constantly whenever the system switch on subbase is placed in “Heat” position, the “B” terminal being constantly energized from R. A thermostat demand for heat completes R-Y circuit, pulling in compressor contactor starting compressor and outdoor motor. R-G also make starting indoor blower motor.

DEFROST CYCLE

The defrost cycle is controlled by temperature and time on the solid state heat pump control.

When the outdoor temperature is in the lower 40° F temperature range or colder, the outdoor coil temperature is 32°F or below. This temperature is sensed by the coil sensor mounted near the bottom of the outdoor coil. Once the coil temperature reaches 32°F or below, the coil sensor sends a signal to the control logic of the heat pump control and defrost timer will start.

After 60 (90 or 30) minutes at 32°F or below, the heat pump control will place the system in the defrost mode.

During the defrost mode, the refrigerant cycle switches back to the cooling cycle, the outdoor motor stops, electric heaters are energized, and hot gas passing through the outdoor coil melts any accumulated frost. When the temperature rises to approximately 57° F, the coil sensor will send a signal to the heat pump control which will return the system to heating operations automatically.

If some abnormal or temporary condition such as a high wind causes the heat pump to have a prolonged defrost cycle, the heat pump control will restore the system to heating operation automatically after 10 minutes.

There are three settings on the heat pump control -- 30 minutes, 60 minutes, and 90 minutes. Most models are shipped wired on the 60 minutes setting for greatest operating economy. If special circumstances require a change to another time, remove wire connected to terminal 60 and reconnect to desired terminal. (See Figure 11.)

There is a cycle speed up jumper on the control. This can be used to reduce the time between defrost cycle operation without waiting for time to elapse.

There is an initial defrost (sen jmp) jumper on the control that can be used at any outdoor ambient during the heating cycle to simulate a 0° coil temperature. This can be used to check defrost operation of the unit without waiting for the outdoor ambient to fall into the defrost region.

START UP NOTES

For improved start up performance, wash the indoor coil with dishwasher detergent

Manual 2100-344 Page 12

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Contents Installation Instructions Single Package Heat Pumps ModelsContents Getting Other Information and Publications Optional FIELD-INSTALLED Electric Heater Table Electrical DataShipping Damage Field Installed Heater Packages OptionalGeneral Instructions GeneralRoof Hood Unit Model Air ConditioningField Fabricated Curbing Location InstallationTypical Installations Airflow and Service Access Clearances Elevated Mounting PlatformsSlab Mounting AT Ground Level Above 32 F Outside Temperature Roof TOP ApplicationMinimum Filter Recommended Model Condensate Drain TrapAIR Filters SizeThermostat Wire Size Wiring Main PowerWiring 24V LOW Voltage Control Circuit FLAThermostats Heat Pump Thermostats Subbase DescriptionEmergency Heat Position Thermostat Indicator LampsCompressor Cutoff Thermostat Wiring 15 KW only Transformer TapsSequence of Operation Three Phase Scroll Compressor Start UP InformationStart UP and Operation Defrost CycleHeat Pump Control Board Service and Troubleshooting Trouble Shooting Guide Checking Temperature Sensor Check OUT Temperature Resistance Temperature SensorBrazing Brazing DiagramSuction and Discharge Tube Pressure 100 105 110 115 Pressure Tables CoolingReturn Air Model HeatingWiring Diagram 4098-123 printed From CAD to get size needed Wiring Diagram 4098-124 printed From CAD to get size needed Wiring Diagram 4098-211 printed From CAD to get size needed

PH1224, PH1236, PH1230 specifications

Bard PH1230, PH1236, and PH1224 are advanced heating and cooling solutions that cater to both residential and commercial spaces. These units are engineered for efficiency, reliability, and comfort, making them ideal choices for any environment. Each model comes equipped with a host of features and technologies that set them apart in the HVAC market.

One of the primary characteristics of the Bard PH series is their compact design. These units are crafted to fit in tight spaces while still delivering powerful performance. This compact nature allows for easier installation, especially in areas where space is a constraint, such as classrooms, offices, and small living areas.

The PH1230, PH1236, and PH1224 all feature a robust and efficient heat pump system. This system allows the units to provide both heating and cooling, making them versatile options throughout the year. The heat pump technology ensures that energy consumption is minimized while maintaining optimal indoor temperatures. This leads to significant savings on energy bills, making these units both environmentally friendly and cost-effective.

Another commendable aspect of the Bard PH series is their advanced filtration system. These units are designed with air quality in mind, featuring high-efficiency filters that capture dust, allergens, and other particles. This not only improves indoor air quality but also enhances the overall comfort of the space. The filters are easily accessible and replaceable, ensuring that maintenance is straightforward and convenient.

Noise reduction technology is another significant feature of the Bard PH units. These models operate quietly, which is particularly beneficial in settings such as classrooms or offices where noise can be disruptive. The innovative design minimizes operational sound levels, creating a more peaceful environment.

Durability is at the forefront of the Bard PH series’ design. Constructed with high-quality materials, these units are built to withstand harsh weather conditions. The exterior casing is resistant to corrosion, ensuring longevity and reliable performance even in the most challenging environments.

In summary, Bard PH1230, PH1236, and PH1224 are exceptional heating and cooling solutions that blend efficiency, versatility, and durability. With features like compact design, advanced heat pump technology, efficient filtration systems, noise reduction capabilities, and robust construction, these units are well-suited for a variety of applications. Whether for residential or commercial use, the Bard PH series stands out as a top choice for anyone looking to enhance comfort and energy efficiency in their space.
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