12
correctly charged.
• If the pressure measured in step 1 is less
than the required liquid refrigerant pressure
determined in step 4, then there is too little
charge in the system. Add refrigerant and
repeat steps 1 through 3 until the system is
correctly charged.
Charging an R-410A Unit in Heating Mode
1. Evacuate the refrigerant system.
2. Weigh in the proper charge as shown on the
unit rating plate. Use the charging charts for
heating mode of operation as a guide (Tables
11 - 16, pages 17 - 19). Tables refl ect conditions
at high speed operation. Unit charge MUST
be verifi ed in cooling season.
3. Verify the unit is operating properly according
to the System Heating section on page 10.
UNIT MAINTENANCE
WARNING:
To prevent electrical shock,
p e r s o n a l i n j u r y, o r d e a t h ,
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 fi lters at the
beginning of each heating and cooling season,
or more frequently if required.
• Inspect the condensate drain and 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 fi lter in the return air
system. Replace disposable fi lters
with the same type and size.
• Do not attempt to add additional oil to motors
unequipped with oil tubes. The compressor is
hermetically sealed at the factory and does
not require lubrication.
COMPONENT FUNCTIONS
Low Pressure Switch
The low pressure switch is factory installed and
located in the suction line internal to the unit. The
switch is designed to protect the compressor if a
loss of charge occurs. Under normal conditions,
the switch is closed.
If the suction pressure falls below 5 psig, then
the switch will open and de-energize the unit. The
switch will close again once the suction pressure
increases above 20 psig. The low pressure
switch interrupts the thermostat inputs to the unit.
NOTE:
When the switch opens and then closes,
there will be a 5 minute short cycling delay before
the unit can energize.
High Pressure Switch
The high pressure switch is factory installed
and located in the compressor discharge line
internal to the 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 650 psig,
the switch will open and de-energize the unit.
The switch will close again once the discharge
pressure decreases to 460 psig. The high
pressure switch interrupts the thermostat inputs
to the unit.
NOTE:
When the switch opens and
then closes, there will be a 5 minute short cycling
delay before the unit can energize.
Содержание Q5RD Series
Страница 23: ...23...
