9
HEAT PUMP MAINTENANCE
WARNING:
To prevent electrical shock, personal injury, or
death, disconnect all electrical power to the unit
before performing any maintenance or service.
The unit may have more than one electrical supply.
Proper maintenance is important to achieve optimum
performance from the heat pump. The ability to properly
perform maintenance on this equipment requires certain
mechanical skills and tools. If you do not possess these
skills, contact your dealer for maintenance. Consult your
local dealer about the availability of maintenance contracts.
Routine maintenance should include the following:
• Inspect and clean or replace air filters at the beginning
of each heating and cooling season, or more frequently
if required.
• Inspect the outdoor coil at the beginning of each cooling
season. Remove any debris. Clean the outdoor coil
and louvers as necessary using a mild detergent and
water. Rinse thoroughly with water.
• Inspect the electrical connections for tightness at the
beginning of each heating and cooling season. Service
as necessary.
CAUTION:
The unit should never be operated without a
filter in the return air system. Replace disposable
filters with the same type and size.
• Do not add additional oil to motors unequipped with oil
tubes. The compressor is hermetically sealed at the
factory and does not require lubrication.
REFRIGERANT CHARGING
WARNING:
This split system heat pump is shipped charged
with R410A refrigerant and ready for installation.
If repairs make it necessary for evacuation and
charging, it should only be attempted by qualified
trained personnel thoroughly familiar with this
equipment. Under no circumstances should
the owner attempt to install and/or service this
equipment. Failure to comply with this warning
could result in property damage, personal injury,
or death.
After refrigerant line connections are completed, it is
required that you leak check and evacuate the indoor
section and all line connections (using proper methods)
before finalizing the full system refrigerant charge.
• To achieve rated capacity and efficiency, the compressor
must be exposed to refrigerant for at least 24 hours
prior to running and then the compressor must be run
for a minimum of 12 hours.
• Cooling mode charging charts are applicable only
to matched assemblies of this equipment and listed
airflows for the indoor coil. Refer to the Quick Reference
Data sheet for additional charging information.
Outdoor units with non-AHRI listed indoor coils are not
recommended and deviations from rated airflows or
non-listed combinations may require modification to the
expansion device and refrigerant charging procedures
for proper and efficient system operation. Refer to
, &
for correct system charging.
• The refrigerant charge can be checked and adjusted
through the service ports provided external to the
outdoor unit. Use only gage line sets which have a
“Schrader” depression device present to actuate the
valve. A common suction port for heating mode charging
is included and located on the compressor access panel
above the outdoor unit service valves.
• Heat mode tables (
) are provided
for quick reference when the unit is in heating mode
and for the inspection of the liquid line pressures and
temperatures.
• A high-pressure switch is factory-installed and located
in the compressor discharge line internal to the
outdoor unit. The switch is designed to de-energize
the system when very high pressures occur during
abnormal conditions. Under normal conditions, the
switch is closed. If the discharge pressure rises above
575 psig, then the switch will open and de-energize
the outdoor unit. The switch will close again once the
liquid pressure decreases to 460 psig. Please note that
the switch interrupts the thermostat inputs to the unit.
When the switch opens and then closes, there will be
a 5 minute short cycling delay before the outdoor unit
will energize.
Charging the Unit in AC mode
(At outdoor temperatures above 55° F for
optimized sub-cooling of 10° F - 12° F.)
1. With the system operating at steady-state, measure the
liquid refrigerant pressure (in psig) at the outdoor unit
service valve.
2. Measure the liquid refrigerant temperature (in
Fahrenheit) at the service valve.
3. Determine the required liquid refrigerant pressure from
,
• If the pressure measured in Step 1 is greater than
the required liquid refrigerant pressure determined in
Step 3, then there is too much charge in the system.
Remove refrigerant and repeat Steps 1 through 3
until the system is correctly charged.
• If the pressure measured in Step 1 is less than the
required liquid refrigerant pressure determined in
Step 3, there is too little charge in the system. Add
refrigerant and repeat Steps 1 through 3 until the
system is correctly charged.
Summary of Contents for T4BD-042 Series
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