If del,rostthemlostatisclosed,speeduppins(J1)mustbeshorted
byplacinga flatheadscrewdriverin betweenfor5 secand
releasing,toobserveacompletedefi'ostcycle.WhentheQuiet
Shiftswitchisselected,compressorwillbeturnedofffortwo30
secintervalsduringthiscompletedefrostcycleasexplained
previously.WhenQuietShiftswitchisinfactorydefaultOFF
position,anormalandcompletedefrostcyclewillbeobserved.
If defrostthermostatisinopenposition,andspeeduppinsare
shorted(withaflatheadscrewdriver)for5secandreleased,a
shortdefi'ostcyclewillbeobserved(actuallengthisdependent
upontheselectedQuietShiftposition).WhenQuietShiftswitchis
in ONposition,thelengthof defi'ostis 1 minute(30sec
compressoroffperiodfollowedby30secofdefi'ostwithcom-
pressoroperation).Onremmtoheatingoperation,compressorwill
againturnoffforanadditional30secandthetimfor40sec.When
theQuietShiftisinOFFposition,onlyabrief30seccyclewillbe
obselwed.
Ifit isdesirabletoobserveacompletedefi'ostinwamlerweather,
thethermostatnmstbeclosedasfollows:
i. Turn off power to outdoor unit.
2. Disconnect outdoor fan motor lead from OF2 on control board
(See Fig. 19.) Tape to prevent grounding.
3. Restart unit in heating mode, allowing frost to accnmnlate on
outdoor coil.
4. After a few minutes in heating mode, liquid line temperature
should drop below closing point of defi'ost thermostat (ap-
proximately 30°F).
NOTE: Unit will remain in def,rost until defrost thermostat
reopens at approximately 80°F coil temperature at liquid line or
remainder of defi'ost cycle time.
5. Turn off power to outdoor and reconnect fan motor lead to
OF2 on control board after above forced defi'ost cycle.
Step 14---Check Charge
UNIT CHARGE
Factory charge is shown on unit rating plate. To check charge in
cooling mode, refer to Cooling Only Procedure. To check charge
in heating mode, refer to Heating Check Chart Procedure.
COOLING ONLY PROCEDURE
NOTE: If superheat or subcooling charging conditions are not
favorable, charge nmst be weighed in accordance with unit rating
plate ± 0.6 ozifl of 3/8-in. liquid line above or below 15 ft
respectively.
EXAMPLE:
To calculate additional charge required for a 25-ft line set:
25 ft - 15 ft 10 ft X 0.6 ozift 6 oz of additional charge
Units installed with cooling mode TXV require charging with the
subcooling method.
i. Operate unit a minimum of i0 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 near
outdoor coil.
4. Refer to Heat Pump Charging Instructions label on outdoor
unit.
5. Refer to Table 4. 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 rd,rigerant if temperature is
lower. Allow a tolerance of ± 3°F.
HEATING CHECK CHART PROCEDURE
To check system operation during heating cycle, refer to the HEAT
Pump Charging Instructions 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 my not be correct. Do not use chart to adjust
refrigerant charge.
NOTE: In heating mode, check refrigerant charge only when
pressures are stable. If in doubt, remove charge and weigh in
correct refrigerant charge.
NOTE: When charging is necessary during heating season,
charge must be weighed in accordance with unit rating plate ± 0.6
oziff of 3/8-in. liquid line above or below 15 ft respectively.
EXAMPLE:
To calculate additional charge required for a 25-ft line set:
25 ft - 15 ft 10 ft X 0.6 oziff 6 oz of additional charge
Step 15--Final Checks
IMPORTANT: Before leaving job, be sure to do the following:
i. Securely fasten all panels and covers.
2. Tighten service valve stem caps to 1i12-tum past finger tight.
3. Leave User's Manual with owner. Explain system operation
and periodic maintenance requirements outlined in manual.
4. Fill out Dealer Installation Checklist and place in customer
file.
CARE AND MAINTENANCE
For continuing high performance and to minimize possible equip-
ment failure, periodic maintenance nmst be performed on this
equipment.
Frequency of maintenance may vary depending upon geographic
areas, such as coastal applications.
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