1. Remove access panel.
2. Drill two 5/16” (8 mm) air test holes in the right front
access panel; hole locations are shown in Figure 6.
Replace the panel.
3. Connect draft gauge. Zero end of draft gauge scale
connects to air entering hole of the coil. Insert gauge
hoses into test holes about 5/16” (8 mm). Seal around
holes with sealant.
4. Turn off power to the outdoor unit, then set the
thermostat for high stage cooling.
1-1/2”
1-1/2”
NOTE
: Remove panel
before drilling test holes.
RIGHT FRONT
ACCESS PANEL
1”
1”
5. Table 4 lists the range of air volumes and equivalent
draft gauge readings for this unit. Observe draft gauge
reading. If reading is above required air volume,
decrease blower speed. Refer to furnace wiring
diagram for changing direct drive blower speed. Do not
exceed maximum air volume as indicated in diagram
blower speed table.
6. After required draft gauge readings are obtained,
remove draft lines and seal air test holes.
7. Set the room thermostat to desired temperature.
A trained technician or service agency must perform
maintenance and service on equipment. At the beginning
of each heating or cooling season, indoor coils should be
cleaned.
on coils. These chemicals are not necessary to dissolve
used to dissolve oils and greases, which generally are not
present on most installations.
Do not use alkaline washes to dissolve oxides such as zinc
oxide, aluminum oxide, and iron oxide (rust). These three
oxides are more corrosion-resistant than base metals.
Dissolving or removing them will cause an increase in
corrosion.
cleaning requires the use of acidic or alkaline cleaners,
cleaner from all equipment components. (Be careful
to prevent damage or corrosion of the components
connected to the system or areas surrounding the
equipment being cleaned.)
1. Remove the coil from the cabinet and take the coil to
an appropriate place to clean it.
2. Vacuum or brush the coil to remove matted and
3. If oil deposits are present, spray the coil with ordinary
household liquid detergent. Allow detergent to soften
deposits. Wait 10 minutes.
For units in coastal regions, fresh water will
dissolve salt deposits. (Wash coils with fresh water at
4. Spray the coil at a vertical angle of 30 to 45 degrees
with a constant stream of water at moderate pressure.
A pressure washer with a fan nozzle will work best. Do
not spray the coil from a horizontal direction.
5. Direct the spray so that any debris is washed out of the
coil and base pan. For most residential units, hot water
is not necessary.
coil will require removing parts from the unit, and it
Attempting to blow water through a coil will slow the
6. Replace the coil into the cabinet.
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