Nortek PPH3RF Series, Руководство по установке

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COMPONENT FUNCTIONS
Low Pressure Switch (Select Models)
- This safety
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
- This safety 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.
UNIT 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 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
filter in the return air system. Replace disposable
filters 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.
REFRIGERANT CHARGING
CAUTION:
This heat pump contains liquid and gaseous
refrigerant under pressure. Adjustment of
refrigerant charge should only be attempted
by qualified, trained personnel thoroughly
familiar with the equipment and safe responsible
refrigerant handling procedures. Under no
circumstances should the homeowner attempt
to install and/or service this equipment. Failure
to comply with this warning could result in
equipment damage, personal injury, or death.
• The unit must be charged while both first and second
stages are operating.
• To achieve rated capacity and efficiency the compressor
must be exposed to refrigerant for at least 24 hours
prior to running and then must be run for a minimum of
12 hours. If Charging in Cooling Mode, see Refrigerant
Charging Charts: .
Charging the Unit in AC Mode
(with Outdoor Temperatures Above 65° F)
1. With the system operating at steady-state, measure
the suction and liquid refrigerant pressures (in psig) at
the service valves.
2. Measure the compressor discharge temperature (° F).
3. Use Figure 10 (page 13) , Figure 11 (page 13) ,
Figure 12 (page 14) , & Figure 13 (page 14) to
verify system conditions (during cooling mode) for
proper charge amount.
Charging the Unit in Heating Mode
1. Evacuate the refrigerant system.
2. Weigh in the proper charge as indicated on the unit
rating label. Unit charge NUST be verified in cooling
season.
3. Verify the unit is operating properly according to the
System Heating section on page 11 .