Bard WA721, WA702-A Start UP, Important Installer Note, Crankcase Heaters, High Pressure Switch

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START UP

IMPORTANT INSTALLER NOTE

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

CRANKCASE HEATERS

WA611, WA70 and WA721 units are provided with compressor crankcase heat.

The WA611, WA70 and WA721 models have a band type heater located around the bottom of the compressor. This heater is controlled by the crankcase heater relay. The heater is only energized when the compressor is not running.

Some form of crankcase heat is essential to prevent liquid refrigerant from migrating to the compressor, casing oil pump out on compressor start-up and possible valve failure due to compressing a liquid.

The decal in Figure 9 is affixed to all WA611, WA70 and WA721 units detailing start-up procedure. This is very important. Please read carefully.

FIGURE 9

START-UP LABEL

IMPORTANT

These procedures must be followed at initial start-up and at any time power has been removed for 12 hours or longer.

To prevent compressor damage which may result from the presence of liquid refrigerant in the compressor crankcase.

1.Make certain the room thermostat is in the "off" position (the compressor is not to operate).

2.Apply power by closing the system disconnect switch. This energizes the compressor heater which evaporates the liquid refrigerant in the crankcase.

3.Allow 4 hours or 60 minutes per pound of refrigerant in the system as noted on the unit rating plate, whichever is greater.

4.After properly elapsed time, the thermostat may be set to operate the compressor.

5.Except as required for safety while servicing – Do not open system disconnect switch.

7961-061

HIGH PRESSURE SWITCH

The WA611, WA70 and WA721 models are supplied with a remote reset high pressure switch. If tripped, this pressure switch may be reset by turning the thermostat off then back on again.

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. All three phase units incorporate a phase monitor to ensure proper field wiring. See the Phase Monitor" section later in this manual.

Verification of proper rotation must be made any time a compressor is change or rewired. 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 ZR3 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 terminal should maintain proper rotation direction.

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 rotations, as well as, substantially reduced current draw compared to tabulated values.

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

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Contents Wall Mounted Packaged AIR Conditioner INSTRUCTIONSWA701-BWA701-C WA702-A WA721Contents Getting Other Information and Publications For More INFORMATION, Contact These PublishersAIR Conditioner Wall Mount Model Nomenclature Wall Mount General InformationElectric Heat Table Unit Dimensions Electrical Specifications General Shipping DamageDuct Work Blower Damper Assembly FiltersFresh AIR Intake Condensate DrainInstallation Instructions Typical InstallationsWiring Main Power Wall Mounting InformationMounting Instructions Wiring LOW Voltage Wiring Thermostat Wire SizeOperating Voltage Range Wall Thermostat and Subbase CombinationsWALL-MOUNTING Instructions Common WALL-MOUNTING Installations Electric Heat Clearance LOW Voltage Wiring Important Installer Note High Pressure SwitchThree Phase Scroll Compressor Start UP Information Start UPSequence of Operation Service HintsCompressor Control Module Adjustments Phase MonitorPressure Service Ports Adjustable Delay on Make and Delay on Break TimerTroubleshooting FAN Blade Setting DimensionsRemoval of FAN Shroud Refrigerant ChargeCooling Pressure All temperatures F Maximum ESP of Operation Electric Heat onlyOptional Accessories Page Page Page

WA701-C, WA701-B, WA611, WA721, WA702-A specifications

The Bard WA702-A, WA721, WA611, WA701-B, and WA701-C are part of Bard's renowned series of wall-mounted HVAC units designed for superior heating and cooling performance in various applications, particularly in the commercial and residential sectors. Each model boasts distinctive features and technologies that cater to specific comfort needs and energy efficiency requirements.

The Bard WA702-A model is noted for its energy-efficient engineering. It utilizes advanced scroll compressor technology, ensuring quiet operation and improved reliability. The unit’s high seasonal energy efficiency ratio (SEER) allows it to operate effectively in a variety of climate conditions, providing economic savings on energy bills.

The WA721 model takes efficiency a step further by incorporating Bard’s innovative electric heat option, which delivers rapid heating capabilities. This model is suitable for colder climates where quick temperature adjustments are essential. Its compact design allows for easy installation without compromising space, making it ideal for both residential and light commercial settings.

The WA611 is engineered with versatility in mind. This model supports multi-zone heating and cooling, allowing users to adjust temperatures in different areas independently. Its advanced controls facilitate optimal comfort while minimizing energy consumption. The WA611 also features an integrated air filtration system to enhance indoor air quality, which is a significant consideration in modern HVAC systems.

For those seeking dual functionality, the WA701-B and WA701-C models stand out with their remarkable heating and cooling capabilities. Both units are equipped with Bard’s patented thermal expansion valve (TXV) that optimizes refrigerant flow for improved efficiency across varying loads. The WA701 series includes robust insulation to reduce noise levels and enhance performance during operation.

In addition to their energy-efficient and space-saving designs, all models feature easy-to-use digital controls, enabling users to adjust settings conveniently. Moreover, the units are constructed with durable materials, providing long-lasting performance even in demanding environments.

Overall, the Bard WA series represents a blend of innovative technology, efficiency, and user-friendly designs that address the ever-changing needs of heating and cooling in contemporary spaces. Whether it’s for residential purposes or commercial applications, these models stand out for their promising performance and reliability, ensuring comfort and satisfaction for users.
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