Nortek PPH3RE Series, Installation Instructions Manual

Page: 12 / 24

12
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 Table 4 (page 14) , Table 5 (page 14) , Table 6
(page 15) , Table 7 (page 15) , Table 8 (page 16) ,
or Table 9 (page 16) to verify system conditions
(during cooling mode) for proper charge amount.
charging the unit in Heating Mode
1. Evacuate the refrigerant system.
2. Use Table 10 (page 17) , Table 11 (page 17) , Table
12 (page 17) , Table 13 (page 18) , Table 14 (page
18) , or Table 15 (page 18) , as a guide and weigh
in the proper charge as shown on the unit rating plate
(during heating mode operation). notE: Unit charge
MUST be verified in cooling season.
3. Verify the unit is operating properly according to the
System Heating section on page 11 .
Safety Switches
• The low pressure switch (if equipped) 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.
• 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.
• 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.
Adjustment of Refrigerant charge
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.