SERVICE HINTS

1.Caution homeowner to maintain clean air filters at all times. Also, not to needlessly close off supply and return air registers. This reduces air flow through the system, which shortens equipment service life as well as increasing operating costs.

2.Check all power fuses or circuit breakers to be sure they are the correct rating.

3.Periodic cleaning of the outdoor coil to permit full and unrestricted airflow circulation is essential.

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. On all 208/230 volt models, when G circuit is de-energized the indoor blower motor will continue to run for one minute. On a call for heating, circuit R-W1 make at the thermostat pulling in heat contact for the strip heat and blower operation. On a call for second stage heat, R-W2 makes bringing on second heat contactor, if so equipped.

COMPRESSOR CONTROL MODULE

The compressor control module is standard on the models covered by this manual. The compressor control is an anti-short cycle/lockout timer with high and low pressure switch monitoring and alarm relay output.

Adjustable Delay On Make And Break Timer

On initial power up or any time power is interrupted to the unit the delay on make period begins which will be 2 minutes plus 10% of the delay on break setting.

When the delay on make is complete and the high pressure switch (and low pressure switch if employed) is closed, the compressor contactor is energized. Upon shutdown the delay or break timer starts and prevents restart until the delay on break and delay on make periods have expired.

During routine operation of the unit with no power interruptions the compressor will operate on demand with no delay.

High Pressure Switch and Lockout Sequence

If the high pressure switch opens, the compressor contactor will de-energize immediately. The lockout timer will go into a soft lockout and stay in soft lockout until the high pressure switch closes and the delay on break time has expired. If the high pressure switch opens again in this same operating cycle the unit will go into manual lockout condition and the alarm relay circuit will energize. Recycling the wall thermostat resets the manual lockout.

Low Pressure Switch, Bypass, and Lockout Sequence

If the low pressure switch opens for more than 120 seconds, the compressor contactor will de-energize and go into a soft lockout. Regardless the state of the low pressure switch, the contactor will reenergize after the delay on make time delay has expired. If the low pressure switch remains open, or opens again for longer than 120 seconds the unit will go into manual lockout condition and the alarm relay circuit will energize. Recycling the wall thermostat resets the manual lockout.

Alarm Relay Output

Alarm terminal is output connection for applications where alarm relay is employed. This terminal is powered whenever compressor is locked out due to HPC or LPC sequences as described.

NOTE: Both high and low pressure switch controls are inherently automatic reset devices. The high pressure switch and low pressure switch cut out and cut in settings are fixed by specific air conditioner or heat pump unit model. The lockout features, both soft and manual, are a function of the Compressor Control Module.

Manual 2100-426 Page 13

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Bard WL701-C, WL701-B, WL702-A installation instructions Service Hints, Sequence of Operation, Compressor Control Module
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WL702-A, WL701-B, WL701-C specifications

The Bard WL702-A, WL701-B, and WL701-C are advanced heating and cooling units designed for efficient and reliable climate control in various applications. These models showcase Bard's commitment to innovation, energy efficiency, and user-friendly features, making them ideal for residential, commercial, and industrial use.

The Bard WL702-A model is a versatile unit, emphasizing energy efficiency with a high Seasonal Energy Efficiency Ratio (SEER). This model employs a variable speed compressor, allowing it to adjust its output based on the current outdoor and indoor temperatures. This flexibility not only enhances comfort but also significantly reduces energy consumption. Additionally, the WL702-A is designed with a robust cabinet construction, ensuring longevity and resistance to harsh weather conditions.

On the other hand, the Bard WL701-B is engineered with a focus on providing reliable heating solutions. It features advanced heat pump technology, utilizing environmentally friendly refrigerants that comply with current environmental standards. The WL701-B is equipped with an integrated defrost control, which minimizes frost buildup and maintains optimal performance in colder climates. Its compact design allows for convenient installation in tight spaces, making it a perfect choice for urban settings.

The Bard WL701-C model takes comfort to the next level with its state-of-the-art smart controls. These controls allow users to set schedules, monitor usage, and adjust settings remotely via a smartphone or tablet application. This model also includes zoning capabilities, enabling customized temperature settings in different areas of a building, leading to enhanced comfort and efficiency. Furthermore, the WL701-C’s quiet operation ensures that occupants can enjoy a peaceful environment, free from disruptive noise.

In summary, the Bard WL702-A, WL701-B, and WL701-C units each bring distinct features and technologies to the table. From the energy-efficient variable speed compressor of the WL702-A to the heat pump technology of the WL701-B and the smart control capabilities of the WL701-C, these models reflect Bard's dedication to providing high-quality climate control solutions that cater to a variety of needs. With their combination of performance, reliability, and ease of use, these units stand out as some of the best options available in the market for effective heating and cooling.
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