Nortek Q7RD Series User Manual

12
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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
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.
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 the cooling charging tables (Tables 3–8 pages
14–16) to verify system conditions for proper charge
amount.
Charging the 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 tables for heating mode of
operation as a guide (Tables 9 - 14, pages 17 - 19).
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.

Nortek Q7RD Series Specifications

General

Brand	Nortek
Model	Q7RD Series
Category	Heat Pump
Language	English