Bard 2100-778 Wall-Mount Heat Pumps User Guide
- June 13, 2024
- Bard
Table of Contents
WALL-MOUNTTM
USER’S APPLICATION
GUIDE AND TECHNICAL
PRODUCT OVERVIEWManual: 2100-778
Supersedes: NEW
Date: 4-6-23
Bard Manufacturing Company, Inc.
Bryan, Ohio 43506
www.bardhvac.com
General Information
The WALL-MOUNT User’s Application Guide covers a wide range of heating and
cooling products manufactured by Bard Manufacturing Company. It is intended to
be a general guide for care and operation of typical systems and covers the
most important features you should be aware of and are responsible for as the
user of the equipment. Because our product offerings are so varied and can be
equipped with many features and options, it is not possible to cover all
aspects of what your specific system may be configured for. Some systems may
be quite simple in features to provide basic cooling and possibly heating,
while other systems may also incorporate various ventilation technologies,
dehumidification circuits and many different internal controls as well as room
temperature controls. Therefore, you should request a detailed operation
sequence and explanation of any special features from your installer and/or
service company and also have them instruct you as to any routine maintenance
procedures you are responsible for.
Please use this guide as a general overview regarding unit application,
maintenance and troubleshooting. Refer to product installation instructions
and supplemental documentation provided with the unit or go to
www.bardhvac.com for detailed individual product
information.
Documentation
There are two sources of valuable information for your new Bard product:
- Documentation provided with your unit, normally located inside the unit control panel during shipping. This information should be saved once the unit is installed for future maintenance reference or to answer questions about equipment after installation.
- Documentation provided on the internet at www.bardhvac.com. This may be accessed from a desktop computer at the office, a laptop or an internet-capable cell phone at the worksite. Up-to-date documentation is available, along with specification sheets and other valuable resources regarding your new Bard product.
Unit Literature Assembly – Documentation Provided with Your Unit
Bard products are shipped with documentation that when used by a technician
with cooling and heating knowledge, can ensure that your product is installed
safely, performs optimally and achieves the longest life cycle possible.
Shipped literature includes the following:
- User Guide (this document)
- Installation Instructions
- Replacement Parts Manual
- User Guide (this document)
- Installation Instructions
- Replacement Parts Manual
Unit Installation
Installation plays a key part in unit functionality, performance and safety.
Product securing and placement, duct design and supply/return location,
electrical routing and condensate and defrost drainage all play key roles in
making sure a unit will perform per the design specifications.
Mounting the Product on a Wall Surface
Outdoor products are normally mounted to an exterior wall surface, including
brick, cement block, metal or wood construction. These products are labeled as
“WALL-MOUNT” units. Before installation begins, the wall surface should be
inspected by a construction professional to ensure it will support the weight
of the unit and accessory items. Approximate weights are available from the
product specification sheet, and a safety factor should be designed into the
installation. Typical fasteners to attach the unit to the wall using the
integrated mounting flanges on both sides of the unit include tap cons, bolts,
studs and other fastening devices. The selection of the fasteners to be used
needs to be reviewed by a construction professional and decided upon based on
the wall construction and fastener strength required. It is important to
follow all guidelines and procedures covered in the installation instructions
manual provided for the product.
Clearances for Outdoor Condenser Fan Airflow
Unit placement and avoidance of obstructions outside the structure are very
critical to unit performance. Avoid installing the unit in areas that will
obstruct outdoor condenser fan airflow or create “pockets” of heated air being
exhausted from the condenser coil. Solid construction fences should not be
placed directly in front of the unit without provisions for condenser airflow.
Solid exterior walls need to be spaced as far away from units as possible to
avoid pockets of heated air causing condenser air recirculation.
Solid barriers located too close to the face or side surfaces (condenser fan
inlet and outlet) of the WALL-MOUNT can both impede airflow and force heated
air to short circuit (be returned) from the condenser outlet to the condenser
inlet. Either condition will effectively raise the condensing temperature and
pressure reducing cooling capacity and efficiency. In extreme cases, the unit
may fail to operate due to high refrigerant pressures inside the unit, and
compressor and/or fan motor failure may occur. Clearances given in
installation instructions ensure components can be serviced and maintenance
can be performed when needed.
National and local electrical codes must be reviewed before unit
installation.
Always use common sense when installing products, follow unit clearances given
in the installation instructions and contact local Bard distributors when
additional knowledge is needed regarding unit clearances for proper unit
functionality.
Clearances for Indoor Supply and Return Airflow
The Bard unit should be placed in an area where the supply (leaving
conditioned air) and return (unit air intake) air paths will be unrestricted.
Avoid placing objects in the structure within 24″ of the return (unit air
intake) grille. Avoid placing objects directly in the path of the supply
(conditioned) air grille. This will inhibit the “throw” of the supply air
throughout the structure and reduce the cooling and/or heating ability of the
unit; in extreme cases, this may cause evaporator coil freezing issues. Supply
air must be able to freely circulate conditioned air throughout the structure.
Adjustment of supply grille deflectors is often necessary to ensure proper
room circulation. Ducted applications should not exceed the rated duct static
pressures given in the unit specification sheets. Special requirements for
duct construction and distances to combustible materials need to be followed
per the installation instructions when electric heating is used.
Condensate and Defrost Drainage
Condensate drainage for air conditioning units needs to be planned before
installation. Your new Bard WALL-MOUNT product includes provisions to allow
condensate water to exit the bottom of the unit. If condensate water is to be
routed away from the unit, adequate drain sizing needs to be provided to allow
proper drainage for condensate water generation. During normal air
conditioning operation, large amounts of condensate water is generated inside
the unit as moisture is extracted from the supply air. This is collected in an
evaporator pan and drained to either a drainage system (indoor products) or
outside the unit cabinet (outdoor products). Evaporator drain traps are not
necessary for any of our wall mounted outdoor products, and the use of
“standing water” U-shaped traps may be prone to freezing in certain climate
zones.
Defrost water drainage from heat pump units needs to be planned before
installation. During seasons requiring heating operation, the unit will need
to warm the condenser coil to remove frost build-up (defrost). Outdoor heat
pump products include holes in the unit base under the condenser coil for
proper water drainage when in the heating defrost cycle. Avoid placing the
unit on a pad or blocking the base drainage holes under the condenser coil
without proper allowances (6″ recommended) for water drainage due to damage
caused by freezing conditions. Without proper drainage, defrost water may
freeze causing ice build up and damage the lower portion of the condenser
coil.
See page 4 for images referencing unit defrost water drainage.
Condensate Water Drainage:
Unit condensate water exits the base of the unit during cooling operation.
Defrost Water Drainage
Holes are provided in the front of
the unit base for heat pump condensate water drainage. 6″ clearance is recommended under WALL-MOUNT heat pump products
to allow proper defrost water drainage.
Power Supply Verification
It is very important to follow all electrical and mechanical safety guidelines
and instructions provided in the product installation instructions. Failure to
do so may result in death, injury or product damage.
A proper power supply to your new Bard unit is very important. Be sure to
verify the following with a multi-meter or other power measuring device before
applying power to your Bard product.
Field-Supplied Voltage
Electrical voltage ratings and proper voltage operating ranges are provided in
the unit specification sheets and installation instructions. It is important
that power supplied to the unit stay in the specified operating voltage range.
Voltage above or below the minimum operating value given could result in
improper unit startup, unit shutdown, low unit performance, improper
thermostat and unit controller operation, compressor damage and premature
failure of functional parts. As a general guideline, it is always best if the
power source for the unit supplies the nominal electrical rating value given
in the specification sheets, installation instructions and unit serial plate
for the product being used. To do so will provide the best unit performance
possible from your new Bard product.
Single and Three Phase Power
Bard products are available in single and three phase power options. It is
important to connect the proper phase listed on the unit serial plate. Three
phase power is often used to reduce energy usage, and units rated for 3 phase
operation are equipped with a phase monitor safety device. The phase monitor
will not allow unit operation with improper phase connection and a red LED
light on the monitor indicates phase wiring issues. Connecting 3 phase power
to a single phase unit will result in component damage and improper unit
operation. Connecting single phase power to a 3 phase unit will also result in
component damage and improper unit operation.
Hertz (Frequency)
Bard products are available in 50hz and 60hz power options. It is important to
connect power with the proper hz value listed on the unit serial plate. 60hz
power is often used in the United States and Canada and units rated for 50hz
operation are normally for international sales outside of this area.
Connecting 50hz power to a 60hz unit not rated for 50hz operation may result
in component damage and improper unit operation. Some equipment may be rated
for 50/60hz operation. Review the unit specifications and installation
instructions for further information regarding the power requirements of the
unit.
Unit Maintenance
Filters and Filter Servicing
All Bard products contain air filters that must be cleaned or replaced on a
regular basis.
Keeping air filter(s) clean is the single most important responsibility of the
user of the equipment. Each type of system must be equipped with an air
filter(s) in the indoor circulating air system to clean the air, keep the
system itself clean for peak efficiency and capacity and prolong the useful
life of the equipment. DO NOT operate the system without the proper air
filters. Filters should be inspected at least monthly and replaced or cleaned
(depending on type) as needed. The useful life of an air filter can vary
widely depending upon application and use of the equipment, and it is critical
to monitor filter condition and establish an acceptable maintenance schedule.
Failure to do so will increase operating and repair costs, decrease capacity
and efficiency and shorten the service life of the equipment. A common symptom
of a dirty filter in the cooling mode is a freeze-up of the indoor coil. The
air filters used may be a disposable (throwaway) type or may be a cleanable
type that can be thoroughly cleaned, rinsed and reused many times. It is
important to make sure that the correct filter size and type for your system
is always used. If there is any question as to acceptable filter size or type,
review the installation instructions for the specific equipment involved, if
available. Otherwise, consult with your installing dealer or service company.
Most equipment can have the filters inspected and serviced by the user with no
problems. In some instances, because of equipment design or specific
installation conditions, it may be necessary to have this procedure done by a
qualified service company. Have your installer or service company show you
where the filter(s) are and demonstrate the service procedure or make
arrangements for them to provide this service on an as-needed basis.
Outdoor Unit Wall Mount Room Air Filters
Wall mount filters are normally accessed from the outside of the building.
Bard does offer a return air grille with a filter frame built-in for indoor
filter access. The return air filter grille is not acceptable as the only
source of filtration if vent options are installed in the wall mount unit.
Return Air Filter Grille:
Bard offers the RFG return air filter grille, which may be used in
applications where outdoor air is not brought into the structure through vent
options. If vent options are used, the filter tray inside the Bard Wall Mount
unit must be used.The built-in filter tray and room air
filters in the wall mount are located in the middle of the cabinet below the
indoor blowers. Units with vent options will have a washable screen behind the
vent intake panel. Coil Cleaning
The outdoor coil must be kept clean and free of any airborne debris, which can
accumulate over time. Large volumes of air are circulated over the coil, and
airborne debris such as lint, dust, materials shed from trees, paper or other
types of airborne material that can become airborne can collect on the
entering coil surface. The outdoor coil must dissipate heat during the cooling
mode and for a heat pump, also absorb heat during the heating mode. If the
coil is dirty and matted with debris, the airflow across the coil will be
reduced causing poor performance, increased operating run time and associated
utility bills and in extreme conditions can shorten the useful life of the
equipment.
Depending on the specific equipment involved, the surface that can accumulate
debris can be on the opposite side that is exposed to view when standing in
front of the machine. Closely review the machine when operating to see which
direction or path the airflow takes as it moves through the machine. If the
air inlet side of the coil is hidden, try to observe the back (hidden) side by
looking into the side grilles, using a flashlight if necessary. While the user
of the equipment needs to be aware of the potential of clogging of the outdoor
coil surface, actual cleaning of the outdoor coil should not be attempted
under most circumstances. If the user should attempt this procedure on their
own, never do so without first having the installing dealer or service company
instruct you in the proper procedure and technique.
WARNING: Do not open or enter the equipment without first turning off the
electrical service disconnect. Failure to do so can result in personal injury
due to moving parts and/or electric shock hazard resulting in death.
Other conditions that can cause reduction of airflow across the outdoor coil
are flowers, shrubbery or other growth too near the outdoor coil air inlet and
outlet openings. These living things, especially as they mature and grow, will
be just as effective in blocking the airflow and create the same problems as
will stacking things against the equipment.
These conditions can be easily managed and controlled by the user, as they do
not require actually entering into the equipment enclosure, which should only
be done by qualified service technicians.
Equipment Corrosion Protection
- Avoid having any lawn sprinkler spray directly on the equipment, especially if from a brackish water source.
- In coastal areas or corrosive environments, locate equipment as far away from the corrosion source as feasible. Units exposed directly to salt spray should be coated by a secondary protective coating operation to reduce corrosion on copper tubing, fasteners, motors and other metal parts. Coils should be ordered with a corrosion protective coating. Contact Bard for coating options.
- Frequent cleaning and waxing of the cabinet using a good automobile polish will help extend its original appearance and protect painted surfaces.
Condenser Airflow
WA, WH, TH, T*S, WRV Wall-
Mount Units:
These units are called “blow through condenser airflow” units because they
draw cool outdoor air from the sides and blow the warm condenser air exiting
the coil through the front grille. CH Wall-Mount Units:
These units are called “draw through condenser airflow” units because they
draw cool outdoor air in the front through the coil and blow the exiting warm
condenser air through the unit sides.
Unit Operation
Air-to-Air Cooling Products (Air Conditioners)
The cooling mode operates similar to a refrigerator, removing heat from inside
the conditioned space and rejecting it outside of the space being controlled.
There are three main parts of the system:
- The evaporator (indoor) coil where cold refrigerant absorbs heat from the air, which circulates from the conditioned space through the machine and is returned to the space at a lower temperature and with some of the humidity (moisture) removed. The moisture exits through a condensate drain system. A motor/blower assembly moves the indoor air through the system.
- The compressor, which is a sealed pump that moves the refrigerant through the system.
- The condenser (outdoor) coil where the heat that was absorbed from the indoor space is discharged to the outdoor environment. A motor/fan system moves the outdoor air across the condenser coil. A properly sized air conditioner cannot cool a structure off rapidly and instead will pull down the temperature slowly. It also will remove a certain amount of moisture (humidity) from the circulating airstream in the process. It may take several hours to pull down a hot, moist building or structure on initial startup or anytime the system has been turned off for a long period of time. It is generally best to set the thermostat at a comfortable temperature and let it control the system as needed, rather than turning it on and off.
Moisture (humidity) removal with a conventional air conditioner (cooling)
unit, or heat pump when operating in the cooling mode, is not directly
controlled and is a by-product of the unit operating to control temperature in
response to the temperature (thermostat) control device. Oversized equipment
can easily control temperature but will have short run-times, thus reducing
its ability to remove moisture from the circulating air stream.
There are also many additional influences that can affect humidity levels
within the conditioned space such as laundry appliances, cooking, showers,
exhaust fans and any other items that can generate moisture or affect its
removal from the space. Therefore, while operation of the air conditioning or
heat pump system in the cooling mode will remove some amount of moisture as it
reduces the air temperature, precise humidity regulation in the conditioned
space cannot be assured and additional equipment such as a dedicated
dehumidifier may be required.
Air-to-Air Cooling and Heating Products (Heat Pumps)
A heat pump is a refrigerant-based system that has additional components and
controls that both heats and cools using a compressor for both modes of
operation. Most heat pumps will also be equipped with some amount of electric
heat to supplement the heating capacity of the compressor system on an as-
needed basis. This operation is entirely automatic and is controlled by the
indoor thermostat and possibly also an outdoor thermostat.
Cooling Mode
The cooling mode of a heat pump is exactly the same as that described for an
air conditioner in the above section.
Heating Mode
The system operates in reverse cycle, meaning that it absorbs and moves heat
from the outdoors and transfers it indoors to be rejected into the circulating
air stream. Even though it seems cold to humans, there is usable heat that can
be extracted efficiently from the outdoor air down to 0ºF, although the colder
the air is there is less heat to extract and the operating efficiency is
diminished.
Defrost Cycle
When operating in the heating mode, the outdoor coil will be colder than the
outdoor air that is forced over it by the fan system. When the outdoor air
temperature is above approximately 40°F, moisture can accumulate on the coil
and it will drain down and out the base of the unit. As the air temperature
gets below approximately 40°F, the coil temperature will start to drop below
32°F, and frost or ice will begin to form on the coil.
An automatic defrost system keeps track of system run time when the outdoor
coil temperature is in the freezing zone and will initiate a defrost cycle at
the appropriate time. The unit continues to operate during the defrost cycle,
but the outdoor fan motor will stop and the reversing valve will shift
positions to flow hot refrigerant gas through the outdoor coil to melt the
accumulated frost. Water will start to drain freely from the unit, and steam
may be emitted from the unit.
The length of the defrost cycle will vary depending upon actual outdoor
temperature, humidity levels and amount of accumulated frost. It could range
from 1-2 minutes up to but not exceeding 8 minutes. When the defrost cycle
terminates, the reversing valve will shift back to heating mode and the
outdoor fan will restart. There is typically a large puff of steam emitted as
the fan restarts. When the heat pump shifts from cool to heating mode, from
heating to cooling mode and especially during defrost cycles, there will be a
pressure transfer sound heard as the reversing valve redirects the flow of
refrigerant. This is commonly described as a hissing noise and is a normal
sound for this type equipment. For air source heat pumps, it is important to
keep heavy snow from accumulating around the machine to the point of blocking
the inlet and outlet openings to the outdoor coil section.
For wall mounted or other equipment that is elevated, this should not be a
factor; but for equipment installed on or near the ground, this can be an
issue in areas prone to heavy and/or blowing snow. The air source heat pump
cannot operate effectively and efficiently when snowbound just as a car cannot
function well in heavy snow conditions.
Dehumidification and Ventilation Operation
Dehumidification
Many Bard systems, typically those used in schools or other commercial
applications, have a dedicated dehumidification capability by having a special
additional refrigeration circuit (factory-installed option only) in addition
to the basic system. These special systems, sometimes also referred to as hot
gas reheat, are designed to control humidity on demand from a humidity
controller much the same as the basic cooling and/or heating system is
controlled by a wall thermostat. Consult your installer and/or service company
to determine if your installation has any of these devices and for any
instructions or maintenance requirements you should be aware of as the user.
Ventilation Options
All Bard systems are available with factory-installed vent options. Most units
can have ventilation field installed after unit installation.
Ventilation has multiple purposes:
- Outside air intake for occupied structures
- Positive pressurization
- Energy savings when outdoor air can be used for cooling
- Agricultural use of bringing in outdoor air and exhausting room air
- Equipment and electronics ventilation
Review product specifications and manuals for more details regarding available
ventilation options and features.
Product documentation is shipped with the product and also available at
www.bardhvac.com.
Troubleshooting
Your Bard product is made to operate for many trouble-free years if installed
properly and maintenance practices are followed. Be sure to verify that all
filters are clean, and condenser coils are free of dirt and debris. Often
these items may look clean at first, but upon closer inspection, show signs of
dirt and debris build-up. New units on new structures may have dirt and dust
in filters from the building construction process.
Thermostats and unit controllers often contain vent holes for proper sensor
measurement inside the device. Make sure the thermostat or controller are not
full of dirt and dust from building construction or years of use.
Verify all requirements in the installation instructions and specification
sheets are met. Unit voltages, airflow clearance requirements and clean unit
power without brownouts or spikes play a critical role in unit performance.
If 208 VAC power is supplied to the unit, the 208V tap must be used on the 24
VAC transformer located inside the control panel. Common sense must also be
used when installing the unit in an environment that may put the unit at risk
of improper operation.
Helpful Hints and Good Operating Practices
The following information will help you enjoy the full comfort and benefits of
your Bard cooling and heating system, maximize the performance and efficiency
and help extend the life of your system.
- Always keep the equipment in peak operating condition with routine scheduled maintenance, especially for the air filters, and to assure a clean outdoor coil.
- For most efficient operation, set the thermostat at the temperature you prefer and then let it take control. If any changes to the settings are required, they should be made in small adjustments and the system be allowed time to respond. Rapid changes either up or down should not be done.
- Setting the thermostat very high does not make the system heat faster and setting it very low does not make it cool faster.
- It is not recommended to turn the system “Off” then back “On” when you need it. This can allow temperature and humidity to build up in warm weather conditions and force the system to run continuously to try and catch up. If the building is to be unoccupied for a lengthy period, it is best to adjust the thermostat to a reasonable higher (or lower—depending on the season) setting rather than turning it completely off. Upon return, the inside conditions will not be totally out of control and recovery time to desired conditions would be much shorter.
- Airflow inside the room or building is very important. Keep all supply registers open and all returns free and unrestricted. Avoid placing objects in areas that will hinder unit airflow. The heating and cooling system is designed to have a certain amount of airflow for proper operation. Therefore, closing off registers, in unused rooms as an example, could reduce airflow below acceptable levels and should not be done without review by your service company who can assess the overall situation and advise you accordingly.
- Heat pumps, especially air-to-air heat pumps, may have the system (compressor) run continuously at lower outdoor temperatures, and this is normal. The heat pump (compressor) mode is controlled by the beginning stages of the thermostat and delivers the most efficient heat. As the outdoor temperature drops off, the heat pump mode heat will also diminish (because there is less heat in the outdoor air to absorb) and must be supplemented by additional electric heat stages, which are not as efficient as the heat pump. The thermostat automatically controls everything and the backup heat will only operate on demand as needed to maintain the desired temperature.
- The thermostat or controller is the user’s primary connection to the system so it is very important to have a thorough understanding of how it works and how to use it properly. Have your installer or service company explain and demonstrate proper operation of the controls.
- Make sure you thoroughly understand how the heating and cooling system itself is intended to operate and what to expect from it. Have your installer or service company explain and demonstrate proper operation of the heating and cooling system.
References
Read User Manual Online (PDF format)
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