Filter
Top Products
—19—
The DFB logic checks the 10-minute defrost timer and the
DFT. If the DFT opens in less than 10 minutes, the DFB
switches the unit back to normal heating operation. If the
DFT remains closed, the DFB switches the unit back to
heating operation after 10 minutes. When the DFB changes
back to heating mode, the RVR (reversing valve relay) is
deenergized and the reversing valve switches back to
heating operation. Both the outdoor and indoor fans come
back on, and if necessary, the electric heater also turns on.
E. System Safeties
The system is equipped with the following safety devices to
protect system components:
Indoor coil freeze protection thermostat — If a coil tempera-
ture of 28 F or lower is sensed, the compressor and outdoor
fan will be shut down until the coil temperature exceeds
28 F. The indoor fan will continue to run.
Condensate float switch (units equipped with accessory
condensate pump, cooling cycle only) — If the level of
condensate in the drain pan rises too high, the condensate
float switch will turn the system off.
F. Special Operation, Heating
Outdoor cooling units may be matched with heat pump
ceiling-suspended fan coil units to provide supplemental
electric heat. All other operation is the same as a cooling-
only system, except these units have heating capability as
follows:
When the room thermostat initiates a call for heating, the
electric heater is turned on. The indoor unit fan will start at
the same time, if it was not already running.
When the heating requirement is satisfied, the room thermo-
stat will open, and the heater will turn off.
CLEANING AND MAINTENANCE
For proper system operation, perform the cleaning and main-
tenance operations in Table 6.
I. LUBRICATION
The indoor-fan, automatic air sweep, and the outdoor-fan
motors are factory lubricated and require no oiling.
II. AIR FILTERS (FIG. 23)
A. Remove Air Filters
Remove filters by pulling them straight out.
B. Clean Or Replace Filters
Filters can be vacuumed or washed in warm water. Shake fil-
ter to remove any excess water, and replace by sliding filter
behind grille until filter snaps in place. Refer to Fig. 23.
If the filter has begun to break down or is torn, replace it.
Replacement filters are available through your dealer.
Table 6 — Cleaning and Maintenance Schedule
NOTE: Maintenance procedures for the outdoor units are in the individual unit installation instructions.
CAUTION: To avoid the possibility of electric
shock, before performing any cleaning and mainte-
nance operations, always turn off power to the system
by pressing the mode button on the remote thermostat
until the display shows “OFF,” and turning off the out-
door disconnect switch located near the outdoor unit. If
the indoor unit is on a separate switch, be sure to turn
this disconnect off as well.
CAUTION: Do not wash filter in water over 120 F
(to avoid shrinkage). Do not expose filter to fire (to
avoid fire damage). Do not expose filter to direct
sunlight. Clean filter more frequently when air is
extremely dirty.
CAUTION: Operating the system with dirty air fil-
ters may damage the indoor unit and, in addition, can
cause reduced cooling performance, intermittent system
operation, frost build-up on the indoor coil, and blown
fuses. Inspect and clean or replace the air filters
monthly.
TASK MONTHLY QUARTERLY YEARLY
INDOOR UNIT
Clean Air Filters X
Clean Drain Pipe X
Clean Condensate Drain Pan X
Clean Indoor Coil X
Clean Indoor Unit Front Panel X
OUTDOOR UNIT
Clean the Fins From Outside X
Open the Unit and Clean Fins Inside X
Remove Dust From Electrical Parts X
Check Electrical Connections are Tight X
Clean Outdoor Fan X
Clean Outdoor Coil X
Check that Outdoor Fan Assembly is Tight X
Clean Drain Pan X
Fig. 22 — Inserting Water into Drain Pan
a40-635