Thermal Expansion Valve System Adjustment; Maintenance - Daikin AWSF18SU16 Series Installation Instructions Manual

For air handler installation, follow the installation procedure
below.
1. Remove the front access panel.
2. Remove access valve fitting cap and depress the valve
system to release pressure. No pressure indicates
possible leak.
3. Replace the fitting cap.
4. Remove the copper cap on both the liquid line and
suction line. The copper caps caused by the refrigerant
lines. DO NOT USE ANY FORM OF CUTTING
METHOD. CUTTING THE CAPS MAY RESULT IN
THE GENERATION OF COPPER SHAVINGS OR
COPPER DUST.
5. Insert liquid line into liquid tube expansion and
slide grommet about 18" away from braze joint.
6. Braze suction line set into suction tube expansion and
slide insulation about 18" away from braze joint.
7. Braze joints and quench all brazed joints with water or
wet rag upon completion of brazing.

10.3 Thermal Expansion Valve System Adjustment

The following information for the indoor unit should be
verified before attempting to charge system or adjust TXV if
necessary.
1. Total static presssure is .3" WC or less.
2. Airflow is correct for installed unit.
3. Airflow tables are in the installation manual and Spec
Sheet for Indoor Unit.
4. Complete airflow tables and charging information are in
Service Manual RS6200006.
5. The outdoor temperature must be 60°F or higher.
6. Set the room thermostat to COOL, fan switch to AUTO
7. Set temperature control well below room temperature.
Superheat adjustments should not be made until indoor
ambient conditions have stabilized. This could take up
to 24 hours depending on the indoor temperature and
humidity. Before checking superheat run the unit in cooling
for 10 minutes or until refrigerant pressures stabilize.
Use the following guidelines and methods to check unit
operation and ensure that the refrigerant charge is within
limits.
1. Purge gauge lines. Connect service gauge manifold to
base-valve service ports.
2. Temporarily install a thermometer on the liquid
line at the liquid line service valve and 4-6" from
the compressor on the suction line. Ensure the
thermometer makes adequate contact and is insulated
for best possible readings. Use liquid line temperature
to determine subcooling and vapor temperature to
determine superheat.
3. Check subcooling and superheat. The system should
have a subcooling of 8°F +/- 1°F and superheat of 8°F
+/- 1°F. If subcooling and superheat are low, adjust
TXV to 8°F +/- 1°F superheat, then check subcooling.
A. If subcooling is low and superheat is high, add
charge to raise subcooling to 8°F +/- 1°F, then
check superheat.
B. If subcooling and superheat are high, adjust
TXV valve to 8°F +/- 1°F superheat, then check
subcooling.
Superheat Adjustments (Only if necessary)
1. Attach a pipe clamp thermometer near the suction line
service valve at the outdoor unit.
A. Ensure the thermometer makes adequate contact
for the best possible readings.
2. TXV-based systems should have a Superheat value of
8°F +/- 1°F.
3. Adjust Superheat by turning the TXV valve stem
clockwise to increase and counterclockwise to
decrease. Adjustments should be made opening or
closing the vlave by no more that 1/4 turn at a time.
Allow the system to stabilize to 15 to 20 minutes before
making additional adjustments if necessary.
4. After adjustments are complete, replace cap on
adjustment stem and tighten 1/6 turn.
5. Remove gauges and check the Schrader ports for
leaks and tighten valve cores if necessary. Install caps
finger tight.
THIS PRODUCT IS FACTORY-SHIPPED WITH R410A/R22 AND
DRY NITROGEN MIXTURE GAS UNDER PRESSURE. USE AP-
PROPRIATE SERVICE TOOLS AND FOLLOW THESE INSTRUC-
TIONS TO PREVENT INJURY.

11 MAINTENANCE

Periodic Checkup and Service
This unit is designed to provide many years of dependable,
trouble-free comfort when properly maintained. Proper
maintenance will consist of annual checkups and cleaning
of the internal electrical and heat transfer components by
a qualified service technician. Failure to provide periodic
checkup and cleaning can result in excessive operating
cost and/or equipment malfunction.
Heater Kit Service
This comfort equipment comes pre-installed with a UL 2-40
certified heater kit. In times of replacement, please ensure
that only a UL 2-40 certified kit is utilized.
7
WARNING