Installation guide

5. SetroomthermostattoCOOLandfancontroltoONorALTO
mode,asdesired.Operateunitfor15minutesChecksystem
refi'igerantcharge.
SEQUENCEOFOPERATION
Turnonpowerto indoorandoutdoorunits.Transformeris
energized.
Onacallforcooling,thermostatmakescircuitsR-YandR-G.
CircuitR-Yenergizescontactor,startingoutdoorfanmotorand
compressorcircuit.R-Genergizesindoorunitblowerrelay,
startingindoorblowermotoronhighspeed.
Whenff_ermostatis satisfied,its contactsopen,de-energizing
contactorandblowerrelay.Compressorandmotorsstop.
If indoorunitis equippedwithatime-delayrelaycircuit,the
indoorblowerwillrunanadditional90sectoincreasesystem
efficiency.
Step 12--Check Charge
UNIT ( HARGE
Factory charge and charging method are shown on unit infbrma-
tion plate. Puron(R) refrigerant cylinders contain a dip tube
which allo_s liquid refrigerant to flow from cylinder in
upright position. Charge Puron® units with cylinder in upright
position and a commercial-Wpe metering device in manifold hose.
Charge refi'igerant into suction line.
NOTE: If superheat or subcooling charging conditions are not
favorable, charge must be weighed in accordance with unit rating
plate, +0.6 ozift 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.
(70()LING ONLY PROCEDURE
Units with (ooling Mode TXV
Units installed with cooling mode TXV require charging by the
subcooling method.
1. Operate unit a n_ininmm of 10 minutes befhre 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 %r required subcooling temperature.
5. Refer to Table 3. Find the point where required subcooling
ternperatme intersects measured liquid service valve pressure.
6. To obtain required subcooting temperature at a specific liquid
line pressure, add refi'igerant if liquid line temperature is
higher than indicated or reclaim refrigerant if temperature is
lower. Allow a tolerance of+ 3°F.
Units with Indoor Pistons
Units installed with indoor pistons require charging by the super-
heat method.
The fbllowing procedure is valid when indoor airflow is within
+21 percent of its rated CFM.
1 Operate unit a mininmm of 10 minutes be%re checking
charge.
2 Measure suction pressure by attaching an accurate gage to
sEfion valve service port.
3 Measure suction temperature by attaching an accurate ther-
mistor type or electronic them_ometer to sEtion line at service
valve.
4 Measure omdoor air dry-bulb temperature with them_ometer.
5 Measure indoor air (entering indoor coil) wet-bulb tempera-
ture with a sling psychrometer
6 Refkr to Table 4. Find outdoor temperature and evaporator
entering air wet-bulb temperature At this intersection, note
superheat.
7 Refkr to Table 5. Find superheat temperature located in item 6
and suction pressure. At this intersection, note suction line
temperature
8 If unit l'ms a higher sEfion line temperature ffmn charted
temperature, add refi'igerant until charted temperature is
reached
9. If unit has a lower suction line temperature than charted
temperatnre, reclaim refi'igerant until charted temperature is
reached.
10. When adding reti'igerant, charge in liquid form into suction
service port using a flow-restricting device.
11 If outdoor air temperature or pressure at suction valve
changes, charge to new suction line temperature indicated on
chart.
Step 13--Final Checks
IMPORTANT: Be%re leaving job, be sure to do the %llowing:
1 Ensure that all wiring is routed away fiom robing and sheet
metal edges to prevent rub=through or wire pinching.
2 Ensure that all wiring and tubing is secure in unit befbre
adding panels and covers Securely _hsten all panels and
COVerS,
3. Tighten service valve stem caps to 1i12-mm past finger tight.
4. Leave Users Manual with owner. Explain system operation
and periodic maintenance requirements outlined in manual.
5. Fill out Dealer Installation Checklist and place in customer
file.
CARE AND MAINTENANCE
For continuing high peKbm_ance and to minimize possible equip-
ment failure, periodic maintenance must be per%treed on this
equipment
Frequency of maintenance may vary depending upon geographic
areas, such as coastal applications. See Users Manual for informa-
tion