Page 25
TSA*S4 SERIES
System Operation
IMPORTANT
Some scroll compressor have internal vacuum protector
that will unload scrolls when suction pressure goes
below 20 psig. A hissing sound will be heard when the
compressor is running unloaded. Protector will reset
when low pressure in system is raised above 40 psig. DO
NOT REPLACE COMPRESSOR.
The outdoor unit and indoor blower cycle on demand from
the room thermostat. When the thermostat blower switch
is in the
ON
position, the indoor blower operates
continuously.
HIGH PRESSURE SWITCH (S4)
TSA*S4 units are equipped with a high-pressure switch
that is located in the liquid line of the compressor as
illustrated in figure 1 on page 2.
MANUAL RESET
BUTTON
Figure 22. High Pressure Switch (S4) Manual Reset
The switch is a Single Pole, Single Throw (SPST),
manual−reset switch which is normally closed and
removes power from the compressor when discharge
pressure rises above factory setting at 590 + 10 psi. The
manual−reset button can be identified by a red cap that is
press to preform the reset function.
Crankcase Heater (HR1)
Crankcase heater HR1 prevents liquid from accumulating
in the compressor. The heater is always on when the
compressor is off. An optional crankcase heater
thermostat (S40) is available.
Table 8. Crankcase Heaters
Parts
Watts
Voltage
M Voltage
40
480
T Voltage
40
240
Maintenance
DEALER
Maintenance and service must be performed by a qualified
installer or service agency. At the beginning of each
cooling season, the system should be checked as follows:
WARNING
Electric shock hazard. Can cause injury
or death. Before attempting to perform
any service or maintenance, turn the
electrical power to unit OFF at disconnect
switch(es). Unit may have multiple power
supplies.
WARNING
Improper installation, adjustment, alteration, service or
maintenance can cause personal injury, loss of life, or
damage to property.
Installation and service must be performed by a licensed
professional installer (or equivalent) or a service agency.
Outdoor Unit
1. Outdoor unit fan motor is pre−lubricated and sealed.
No further lubrication is needed.
2. Visually inspect all connecting lines, joints and coils for
evidence of oil leaks.
3. Check all wiring for loose connections.
4. Check for correct voltage at unit (unit operating).
5. Check amp draw on outdoor fan motor.
Motor
Nameplate
:_________
Actual
:__________.
6. Inspect drain holes in coil compartment base and
clean if necessary.
NOTE - If insufficient cooling occurs, the unit should be
gauged and refrigerant charge should be checked.
Outdoor Coil
Clean and inspect outdoor coil (may be flushed with a
water hose). Ensure power is off before cleaning.
NOTE It may be necessary to flush the outdoor coil
more frequently if it is exposed to substances which are
corrosive or which block airflow across the coil (e.g., pet
urine, cottonwood seeds, fertilizers, fluids that may contain
high levels of corrosive chemicals such as salts)
Sea Coast
Moist air in ocean locations can carry salt,
which is corrosive to most metal. Units that are located
near the ocean require frequent inspections and
maintenance. These inspections will determine the
necessary need to wash the unit including the outdoor coil.
Consult your installing contractor for proper
intervals/procedures for your geographic area or service
contract.
Indoor Unit
1. Clean or change filters.
2. Lennox blower motors are prelubricated and
permanently sealed. No more lubrication is needed.
