Installation Manual

INST ALLATION INSTRUCTIONS R- 410A Split System Heat Pumps
428 01 5110 00 9
Specifications subject to change without notic e.
START- UP PROCEDURE
1. Set indoor thermostat selector switch to OFF.
2. T urn ON all electrical disconnect devices.
3. If unit has a crankcase heater, energize the heater
and wait 24 hours before proceeding.
4. Set indoor thermostat at desired temperature. Be
sure setpoint is below indoor ambient temperature
to call for cooling, or above indoor ambient to call
for heating.
5. Set indoor thermostat selector switch to COOL or
HEAT. Operate unit for minimum 15 minutes, then
check the system refrigerant charge.
REFRIGERANT CHARGE
Factory charge amount and desired subcooling are
shown on unit rating plate. Charging method is shown on
information plate inside unit. Additional subcooling may
be required to achieve optimal heating performance
based on installed indoor unit.
For TXV, use subcooling method.
For Piston, use superheat method.
To properly check or adjust charge, conditions must be
favorable for subcooling or superheat charging.
Favorable conditions exist when the outdoor
temperature is between 70_F and 100_F(21_C and
38_C), and the indoor temperature is between 70_F and
80_F(21_C and 27_C). Follow the procedure below.
Unit is factory charged for 15 feet (4.6m) of lineset.
Adjust charge by adding or removing 0.6 oz/ft (17 g/mm)
of 3/8 liquid line above or below 15 feet (4.6 m)
respectively.
For standard refrigerant line lengths 80 feet (24.4m) or
less, allow system to operate in cooling mode at least 15
minutes. If conditions are favorable, check system
charge by super heat method for fixed metering device
and subcooling method for TXV. If any adjustment is
necessary, adjust charge slowly and allow system to
operate for 15 minutes to stabilize before declaring a
properly charged system.
If the indoor temperature is above 80_F(27_C), and the
outdoor temperature is in the favorable range, adjust
system charge by weight based on line length and allow
the indoor temperature to drop to 80_F(27_C) before
attempting to check syst em charge by subcooling
method as described above.
If the indoor temperature is below 70_F(21_C), or the
outdoor temperature is not in the favorable range, adjust
charge for line set length above or below 15 feet (4.6m)
only. Charge level should then be appropriate for the
system to achieve rated capacity. The charge level could
then be checked at another time when the both indoor
and outdoor temperatures are in a more favorable range.
NOTE: If line length is beyond 80 feet (24.4m) or greater
than 20 feet (6.1m) vertical separation, See Long Line
Guideline for special charging requirements.
COOLING MODE
Units installed with cooling mode TXV require charging
by the subcooling method.
1. Operate unit a minimum of 15 minutes before
checking charge.
2. Measure liquid service valve pressure by
attaching an accurate gage to service port.
3. Measure liquid line temperature by attaching an
accurate thermistor type or electronic
thermometer to liquid line near outdoor coil.
4. Refer to unit rating plate for required subcooling
temperature.
5. Refer to Table 3. Find the point where required
subcooling temperature intersects measured
liquid service valve pressure.
6. To obtain required subcooling temperature at a
specific liquid line pressure, add refrigerant if
liquid line temperature is higher than indicated or
reclaim refrigerant if temperature is lower . Allow a
tolerance of 3_F(1.7
_C).
C. HEATING MODE
To check system operation during heating cycle, refer to
the Tech Label on outdoor unit. This chart indicates
whether a correct relationship exists between system
operating pressure and air temperature entering indoor
and outdoor units. If pressure and temperature do not
match on chart, system refrigerant charge may not be
correct. Do not use chart to adjust refrigerant charge.
NOTE: When charging is necessary during heating
season, charge must be weighed in accordance with unit
rating plate 0.6 ounces per foot of an inch liquid line
above or below 15 feet respectively (17g per 305mm of
10mm liquid line above or below 4.6m respectively).