INSTALLATION INSTRUCTIONS

Getting Other Information and Publications

These publications can help you install the air conditioner or heat pump. You can usually find these at your local library or purchase them directly from the publisher. Be sure to consult the current edition of each standard.

• National Electrical Code: ANSI/NFPA 70
• Standard for the Installation of Air Conditioning and Ventilating Systems: ANSI/NFPA 90A
• Standard for Warm Air Heating and Air Conditioning Systems: ANSI/NFPA 90B
• Load Calculation for Residential Winter and Summer Air Conditioning: ACCA Manual J
• Duct Design for Residential Winter and Summer Air Conditioning and Equipment Selection: ACCA Manual D

FOR MORE INFORMATION, CONTACT THESE PUBLISHERS:

• ACCA
  Air Conditioning Contractors of America
  1712 New Hampshire Ave. N.W.
  Washington, DC 20009
  Telephone: (202) 483-9370
  Fax: (202) 234-4721
• ANSI
  American National Standards Institute
  11 West Street, 13th Floor
  New York, NY 10036
  Telephone: (212) 642-4900
  Fax: (212) 302-1286
• ASHRAE
  American Society of Heating, Refrigeration and Air Conditioning Engineers, Inc.
  1791 Tullie Circle, N.E.
  Atlanta, GA 30329-2305
  Telephone: (404) 636-8400
  Fax: (404) 321-5478
• NFPA
  National Fire Protection Association
  Batterymarch Park
  P.O. Box 9101
  Quincy, MA 02269-9901
  Telephone: (800) 344-3555
  Fax: (617) 984-7057

Manufactured under the following U.S. Patent numbers: 5,485,878; 5,301,777; 5,002,116; 4,924,934; 4,875,520; 4,825,936

Wall Mount General Information

Wall Mount Model Nomenclature

The model nomenclature indicates specific features of the unit:

• W: Wall Mounted
• Capacity (e.g., 18, 24, 30, 36, 42, 48, 60): Represents tonnage (1.5 Ton, 2 Ton, etc.).
• A or L: A = Air Conditioner, L = Left Hand Air Conditioner (compressor and controls on the left).
• Volts & Phase (e.g., A=230/208/60/1, B=230/208/60/3, C=460/60/3): Specifies electrical requirements.
• Revisions (e.g., 10): Indicates model revisions.
• KW: Kilowatts of electric heat.
• Ventilation Options (X, B, M, V, E, R): Indicate fresh air intake configurations (Barometric Fresh Air Damper, Blank-off Plate, Motorized Fresh Air Damper, Commercial Ventilator, Economizer, Energy Recovery Ventilator). Note: X, B, M options are without exhaust capability and may require field-supplied barometric relief.
• Coil Options (X, 1, 2, 3): Standard, Phenolic Coated Evaporator, Phenolic Coated Condenser, or both.
• Color Options (X, 1, 2, 4, 5, 6): Beige, White, Mesa Tan, Buckeye Gray, Desert Brown, Dark Bronze.
• Filter Options (X, W, P): One Inch Throwaway (standard), One Inch Washable, or Two Inch Pleated.
• Outlet Options (X, T): Front (standard) or Top Outlet (for W30A, W36A only).
• Control Modules: Refer to Specification Sheet S3397.

Shipping Damage

Upon receipt of equipment, inspect the carton for external signs of shipping damage. If damage is found, contact the carrier immediately, preferably in writing, to request an inspection by their agent.

General

This equipment is intended for installation by trained, experienced service and installation technicians. The refrigerant system is fully assembled and charged, and all internal wiring is complete. The unit is designed for use with or without duct work, with flanges provided for attaching supply and return ducts. These instructions detail the recommended installation method for the air-cooled self-contained unit and its electrical connections.

Read these instructions and any accompanying instructions for separate equipment carefully before beginning installation. Pay particular attention to the "Starting Procedure" and any tags or labels attached to the equipment.

While these instructions serve as a general guide, they do not supersede national or local codes. Consult authorities having jurisdiction before installation. Refer to Page 3 for codes and standards information.

Unit sizing should be based on heat loss calculations using methods from the Air Conditioning Contractors of America (ACCA). Air duct installation must comply with NFPA No. 90A (Other Than Residence Type) and NFPA No. 90B (Residence Type Warm Air Heating and Air Conditioning Systems). Adhere to local codes if they differ from these instructions.

Duct Work

All supply and return ductwork must be properly sized for the equipment's design airflow requirement. ACCA provides excellent guidance for proper sizing. Ductwork not within the conditioned space should be insulated (minimum one inch with a vapor barrier on the outside) to conserve energy and prevent condensation or moisture damage. Flexible joints should be used to minimize noise transmission.

Refer to Table 6 for Maximum ESP of operation for electric heat.

For models W18 & W24, zero inch clearance to the supply duct is permitted. For models W30, W36, W42, W48, and W60, a 1/4 inch clearance to combustible material is required for the first three feet of duct attached to the outlet air frame. Refer to Wall Mounting Instructions and Figures 3 and 4 for details.

Ducts passing through walls must be insulated, and all joints taped or sealed to prevent air or moisture ingress.

Some installations may not require a return air duct. In such cases, a metallic return air grille is required. The grille louvers should not exceed 5/8 inch spacing. Bard Return Air Grille Kits RG2-RG5 or RFG2-RFG5 are recommended. If a return air filter grille is used, ensure the filter is sized for a maximum velocity of 400 fpm.

If no return air duct is used, applicable installation codes may restrict installation to single-story structures.

Filters

A standard 1-inch throwaway filter is included. It is accessible from the outside via a filter access panel. Optional 1-inch washable or 2-inch pleated filters are available. The internal filter brackets can be adjusted for a 2-inch filter by bending two tabs on the support bracket.

Fresh Air Intake

Units are equipped with fresh air inlet slots on the service door. If a fresh air damper assembly is included, it is shipped attached to the unit with the damper blade locked closed. Maximum and minimum blade position stops must be installed for damper operation. See Figure 1.

Capacity, efficiency, and cost of operation information is based on the fresh air blank-off plate being in place for maximum energy efficiency. The blank-off plate can be requested from the factory as a replacement for the fresh air damper.

Condensate Drain

A plastic drain hose extends from the unit's drain pan to the base. Openings in the base allow the hose to pass through. If connected to a drain system, it must be an open or vented type to ensure proper drainage.

Figure 1: Fresh Air Damper
Diagram illustrating the fresh air damper assembly.

Installation Instructions

Wall Mounting Information

1. Cut two holes in the wall for supply and return air openings as shown in Figure 3.
2. Ensure wood frame walls are strong and rigid enough to support the unit's weight without transmitting vibration.
3. Thoroughly inspect concrete block walls to confirm they can support the installed unit's weight.

Mounting the Unit

1. Units are secured by wall mounting brackets attached to the outside wall surface on both sides. A bottom mounting bracket, attached to the skid for shipping, is provided for ease of installation but is not mandatory.
2. The unit itself requires 0 inch clearance. However, the supply air duct flange and the first 3 feet of supply air duct require a minimum 1/4 inch clearance to combustible material for models W30, W36, W42, W48, and W60. A 1-inch clearance is generally recommended for easier installation and to maintain clearance to combustible material. See Figure 3 for opening size details.
3. Locate and mark lag bolt locations and the bottom mounting bracket location (refer to Figure 3).
4. Mount the bottom mounting bracket.
5. Hook the top rain flashing (attached to the front-right of the supply flange for shipping) under the back bend of the top.

6. Position the unit in the opening and secure with 5/16 lag bolts, using 7/8 inch diameter flat washers.
7. Secure the rain flashing to the wall and caulk the entire length of the top. See Figure 3.
8. For added mounting rigidity, drill and screw or weld the return air and supply air frames/collars to the structural wall (depending on construction). Ensure required clearance is maintained if the wall is combustible.
9. For side-by-side installations, maintain a minimum of 20 inches clearance on the right side for access to the control panel and heat strips, and for proper outdoor coil airflow. Additional clearance may be needed to meet local or national codes.

Clearances Required for Service Access and Adequate Condenser Airflow

NOTE: For side-by-side installation of two (2) W**A models, maintain 20" between units. This can be reduced to 15" by using a W**L model (left side compressor and controls) for the left unit and a W**A model (right side compressor and controls) for the right unit. See W**A Specification S3397 & W**L Specification S3279.

Minimum Clearances Required to Combustible Materials

Figure 2: Unit Dimensions
Table detailing nominal dimensions for architectural and installation requirements. Diagrams show front, side, and back views of W**A (Right Unit) and W**L (Left Unit) models, indicating key features like access panels, mounting brackets, and air inlets/outlets.

Figure 3A: W18A1, W18L1, W24A1, W24L1 Mounting Instructions
Diagram illustrating mounting details and dimensions for W18 and W24 series units.

Figure 3B: W30A1, W30L1, W36A1, W36L1 Mounting Instructions
Diagram illustrating mounting details and dimensions for W30 and W36 series units, including required clearances to combustible materials.

Figure 3C: W42A1, W42L1, W48A1, W48L1, W60A1, W60L1 Mounting Instructions
Diagram illustrating mounting details and dimensions for W42, W48, and W60 series units, including required clearances to combustible materials.

Figure 4: Electric Heat Clearance
Diagram showing a side section view of the supply air duct for wall-mounted units, highlighting the required 1/4 inch clearance to combustible surfaces for the first 3 feet of ducting. Includes a warning about fire hazard due to insufficient clearance.

Figure 5: Wall Mounting Instructions
Diagrams showing concrete block wall installation and wood frame wall installation, referencing Figure 3 for mounting instructions.

Figure 6: Wall Mounting Instructions
Diagram illustrating unit mounting within a wall opening, showing clearances and attachment points to wall framing. References Figure 2 for unit dimensions.

Figure 7: Common Wall Mounting Installations
Diagrams illustrating various installation scenarios: free air flow (no duct), ducted supply and return at unit, false wall installation, and closet installation.

Wiring - Main Power

Refer to the unit rating plate for wire sizing and maximum fuse or HACR type circuit breaker size. The "Minimum Circuit Ampacity" on the unit indicates the required current carrying capacity for field wiring. Depending on the electric heat KW, two field power circuits may be needed, as indicated on the serial plate. All models require copper conductors only, as marked on the unit and wiring diagrams. Adhere to the National Electrical Code (NEC) and local codes for current carrying capacity data and wiring practices.

Electrical data lists fuse and wire sizes (75°C copper) for all models, including common heater sizes, and the number of field power circuits required for models with heaters.

The unit rating plate specifies the "Maximum Time Delay Relay Fuse" or "HACR" type circuit breaker for proper circuit protection and to prevent nuisance tripping from momentary high starting current.

The disconnect access door can be locked to prevent unauthorized access. To enable locking, bend the tab in the bottom left corner of the disconnect opening outwards; it will then align with the door slot for padlock insertion.

Refer to the "Start Up" section for three-phase scroll compressor start-up information. Consult Tables 4 & 5 for Electrical Specifications.

Wiring - Low Voltage Wiring

Units with dual primary voltage transformers (230/208V, 1-phase and 3-phase) are factory wired to the 240V tap. For 208V operation, reconnect to the 208V tap. The acceptable operating voltage ranges are:

• 240V Tap: 253-216V
• 208V Tap: 220-187V

NOTE: Measure voltage at the field power connection point while the unit operates at full load (maximum amperage).

For wiring size and connections, refer to Wiring Manual 2100-507.

Start Up

THESE UNITS REQUIRE R-410A REFRIGERANT AND POLYOL ESTER OIL.

GENERAL:

1. Use separate service equipment to avoid cross-contamination of oil and refrigerants.
2. Use recovery equipment rated for R-410A refrigerant.
3. Use manifold gauges rated for R-410A (800 psi/250 psi low).
4. R-410A is a binary blend of HFC-32 and HFC-125.
5. R-410A is nearly azeotropic (similar to R-22 and R-12). Charge with liquid refrigerant.
6. R-410A operates at 40-70% higher pressure than R-22; R-22 systems cannot withstand this pressure.
7. R-410A has zero ozone depletion potential but must be reclaimed due to its global warming potential.
8. R-410A compressors use polyolester oil.
9. Polyol Ester oil is hygroscopic and absorbs moisture, holding it within the oil.
10. A liquid line dryer is essential; deep vacuum alone cannot remove moisture from the oil.
11. Limit atmospheric exposure to 15 minutes.
12. If compressor removal is necessary, plug it immediately. Purge with nitrogen when inserting plugs.

TOPPING OFF SYSTEM CHARGE

If a leak has occurred, Bard Manufacturing recommends reclaiming, evacuating, and charging to the nameplate charge. Topping off can be done without issues if performed correctly.

With R-410A, refrigerant composition changes are minimal with multiple leaks and recharges. R-410A is nearly an azeotropic blend. The remaining refrigerant can be used after leaks, and the charge can be topped off using charging charts on the inner control panel cover.

REMEMBER: When adding R-410A refrigerant, draw it as a liquid from the cylinder/tank to avoid fractionation and ensure optimal performance. Refer to cylinder instructions for the proper liquid extraction method.

SAFETY PRACTICES:

1. Never mix R-410A with other refrigerants.
2. Use gloves and safety glasses. Polyol Ester oils can irritate skin, and liquid refrigerant can freeze skin.
3. Never use air and R-410A for leak checks, as the mixture can become flammable.
4. Do not inhale R-410A. It can cause dizziness, loss of coordination, slurred speech, cardiac irregularities, unconsciousness, and potentially death.
5. Do not burn R-410A, as decomposition produces hazardous vapors. Evacuate the area if exposed.
6. Use only cylinders rated DOT4BA/4BW 400.
7. Never fill cylinders over 80% of total capacity.
8. Store cylinders in a cool area, out of direct sunlight.
9. Never heat cylinders above 125°F.
10. Never trap liquid R-410A in manifold sets, gauge lines, or cylinders. R-410A expands significantly with temperature increases, which can cause bursting.

Start Up (Continued)

IMPORTANT INSTALLER NOTE

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

HIGH PRESSURE SWITCH

All W**A/W**L wall-mounted air conditioner series models have a remote reset for the high and low pressure switches. If tripped, reset by turning the thermostat off and then back on.

THREE PHASE SCROLL COMPRESSOR START UP INFORMATION

Scroll compressors, like other types, compress in one rotational direction. Single-phase compressors always start and run in the correct direction. Three-phase compressors rotate based on power phasing; reverse rotation can occur if power leads are reversed.

Verify proper rotation by observing suction pressure drop and discharge pressure rise when the compressor is energized. Reverse rotation also causes higher sound levels and substantially reduced current draw compared to tabulated values.

Verification must be done at the time of service. Correcting improper rotation immediately has no negative impact on compressor durability. However, running in reverse for over an hour can negatively impact bearings due to oil pump-out.

NOTE: If a compressor runs in reverse for several minutes, its internal protector will trip.

All three-phase ZP compressors are wired identically internally. Connecting properly phased power leads to the same Fusite terminal ensures correct rotation. Reversing any two line connections will change the direction of rotation.

PHASE MONITOR

Units with three-phase scroll compressors have a 3-phase line monitor to prevent compressor damage from phase reversal. The monitor has two LEDs: a green LED indicates correct phasing (Y signal present), while a red fault LED indicates reversed phases and inhibits compressor operation.

If a fault occurs, reverse two of the supply leads to the unit. Do not reverse factory wires, as this may cause damage.

CONDENSER FAN OPERATION

Applies to W42, W48, and W60 models. The condenser fan motor on 230/208 volt, 60 Hz units is a two-speed motor, factory wired for high speed. It can be reconnected to low speed (red wire) for lower sound levels if ambient conditions permit (see wiring diagram). 50 Hz models are factory wired for low speed.

SERVICE HINTS

1. Advise owners to maintain clean air filters and avoid unnecessarily closing supply and return air registers, as this reduces airflow, shortens service life, and increases operating costs.
2. Verify all power fuses or circuit breakers are the correct rating.
3. Periodically clean the outdoor coil to ensure full and unrestricted airflow.

Sequence of Operation

COOLING

When the thermostat calls for cooling (R-Y circuit), the compressor contactor engages, starting the compressor and outdoor motor. The G circuit (indoor motor) engages automatically or via manual fan switch for constant air circulation. For heating, R-W1 engages the heat contactor and blower. R-W2 engages the second stage heat contactor if equipped.

COMPRESSOR CONTROL MODULE

The standard compressor control module 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 after power interruption, a delay-on-make period begins (2 minutes + 10% of delay-on-break setting). Once this delay expires and pressure switches are closed, the compressor contactor energizes. Upon shutdown, a delay-on-break timer prevents restart until both delay periods have passed. During normal operation without power interruptions, the compressor runs on demand with no delay.

High Pressure Switch and Lockout Sequence

If the high pressure switch opens, the compressor contactor de-energizes immediately. The unit enters a soft lockout state until the high pressure switch closes and the delay-on-break time expires. If the switch opens again in the same cycle, the unit enters manual lockout, and the alarm relay circuit energizes. Recycling the wall thermostat resets manual lockout.

Low Pressure Switch, Bypass, and Lockout Sequence

If the low pressure switch opens for over 120 seconds, the compressor contactor de-energizes into a soft lockout. The contactor will re-energize after the delay-on-make time expires, regardless of the low pressure switch state. If the switch remains open or opens again for over 120 seconds, the unit enters manual lockout, and the alarm relay circuit energizes. Recycling the wall thermostat resets manual lockout.

Alarm Relay Output

The alarm terminal provides an output connection for applications using an alarm relay. This terminal is powered when the compressor is locked out due to HPC or LPC sequences.

NOTE: High and low pressure switch controls are automatic reset devices. Cut-in/cut-out settings are fixed by model. Soft and manual lockout features are part of the Compressor Control Module.

ADJUSTMENTS

Adjustable Delay on Make and Delay on Break Timer

A potentiometer sets the Delay on Break (DOB) time from 30 seconds to 5 minutes. Delay on Make (DOM) timing on power-up and after interruptions equals 2 minutes + 10% of DOB:

• 0.5 min (30s) DOB = 123s DOM
• 1.0 min (60s) DOB = 126s DOM
• 2.0 min (120s) DOB = 132s DOM
• 3.0 min (180s) DOB = 138s DOM
• 4.0 min (240s) DOB = 144s DOM
• 5.0 min (300s) DOB = 150s DOM

During routine operation, the compressor runs on demand with no delay.

Typical Settings for Dual Unit Installation:

• Unit 1: DOB set at 2 minutes, DOM is 132 seconds.
• Unit 2: DOB set at 4 minutes, DOM is 144 seconds.

PRESSURE SERVICE PORTS

High and low pressure service ports are installed on all units for observing system operating pressures. A pressure table is provided later in the manual, which must be matched to the unit by model number. See Table 3.

Troubleshooting

FAN BLADE SETTING DIMENSIONS

Figure 8 shows the correct fan blade setting for proper outdoor coil air delivery. Refer to Table 1 for specific unit dimensions. Any service work on the fan or motor area requires checking these dimensions and adjusting the blade position on the motor shaft accordingly.

Figure 8: Fan Blade Setting
Diagram illustrating fan blade setting and dimension 'A'.

TABLE 1: FAN BLADE DIMENSION

REFRIGERANT CHARGE

The correct R-410A system charge is indicated on the unit rating plate. Optimal performance is achieved with a charge resulting in the suction line temperature (6" from compressor) shown in Table 2. If charge quantity is uncertain, reclaim the unit and recharge to the factory nameplate quantity.

TABLE 2: REFRIGERANT CHARGE

Suction line temperatures in Table 2 are based on 80°F dry bulb / 67°F wet bulb (50% R.H.) temperature and rated airflow across the evaporator during cooling.

REMOVAL OF FAN SHROUD

1. Disconnect all power to the unit.
2. Remove screws holding both grilles (one on each side) and remove the grilles.
3. Remove screws holding the fan shroud to the condenser and bottom (nine screws total).
4. Unwire the condenser fan motor.
5. Slide the motor, fan blade, and shroud assembly out the left side of the unit.
6. Service the motor/fan as needed.
7. Reverse steps to reinstall.

TABLE 3: COOLING PRESSURE TABLE

Provides cooling pressure readings based on Air Temperature Entering Outdoor Coil (°F) and Return Air Temperature (DB/WB).

Low side pressure: ± 2 PSIG
High side pressure: ± 5 PSIG

Tables are based upon rated CFM (airflow) across the evaporator coil. If there is any doubt as to correct operating charge being in the system, the charge should be removed, system evacuated and recharged to serial plate charge weight.

NOTE: Pressure table based on high speed condenser fan operation. If condensing pressures appear elevated, check condenser fan wiring. See "Condenser Fan Operation".

TABLE 4: Electrical Specifications -- W**A Series

Details electrical specifications for W**A series models, including rated voltage/phase, number of field power circuits, minimum circuit ampacity, maximum fuse/breaker size, field power wire size, and ground wire size for single and dual circuits.

TABLE 5: Electrical Specifications -- W**L Series

Details electrical specifications for W**L series models, including rated voltage/phase, number of field power circuits, minimum circuit ampacity, maximum fuse/breaker size, field power wire size, and ground wire size for single and dual circuits.

TABLE 6: RECOMMENDED AIRFLOW

* Rated CFM and ESP on high speed tap.

TABLE 7: INDOOR BLOWER PERFORMANCE

Provides indoor blower performance data (CFM) for various E.S.P. (Inches H2O) and speed settings for different model series.

TABLE 8: MAXIMUM ESP OF OPERATION ELECTRIC HEAT ONLY

Details maximum ESP values for electric heat operation across different models and speeds.

Values are for units with standard 1-inch throwaway or 1-inch washable filters. Derate ESP by .15 for 2-inch pleated filters.

TABLE 9: ELECTRIC HEAT

Provides electric heat specifications (KW, Amps, BTUH) for various voltage and phase configurations.

TABLE 10: OPTIONAL ACCESSORIES

Lists optional accessories, including Heater Kits and Circuit Breakers/Pull Disconnects, with part numbers and applicable model series.

TABLE 11: VENT & CONTROL OPTIONS

Lists available vent and control options with part numbers, descriptions, and applicable model series (W18, W24; W30, W36; W42, W48, W60).