Sequence Of Operation; Cooling; Yim-A; Secure Owner's Approval - York D1EB036 Installation Manual

SEQUENCE OF OPERATION

COOLING

The following sequences of operation are based on using a
standard single-stage cooling thermostat.
WITH POWER TO UNIT AND THERMOSTAT IN COOLING
MODE
1. If the fan switch on the thermostat is in the "ON" position,
the 24 volts at "G" will energize the "K1" relay on the fan
control board, close the "K1" relay contacts, and ener-
gize the indoor blower motor. If the fan switch is in the
"AUTO" position, the blower will operate only when there
is a call for cooling by the thermostat.
2. On a call for cooling, the thermostat will send 24 volts to
"Y" on the fan control board. The 24 volt signal will ener-
gize contactor "M1", and power will be supplied to the
compressor and outdoor fan motor. If the fan switch on
the thermostat is on the "AUTO" position, the thermostat
will also send a 24 volt signal to "G" on the fan control
board and the indoor blower will operate as indicated in
step 1.
3. When the demand for cooling has been satisfied, the
"M1" contactor will be de-energized when the 24 volt "Y"
signal is removed. If the fan switch on the thermostat is
energized when the 24 volt "Y" signal is removed. If the
fan switch on the thermostat is in the "ON" position, the
indoor blower will continue to run. If the fan switch is in
the "AUTO" position, the 24 volt "G" signal will be
removed, and after a 60 second delay, the "K1" relay will
open and de-energize the indoor blower motor.
TABLE 12: THERMOSTAT SIGNALS
ON FAN INSTANT ON
"G"
OFF FAN INSTANT OFF
FAN INSTANT ON
ON
COMPRESSOR AND OUTDOOR FAN INSTANT ON
"G"
"Y"
COMPRESSOR AND OUTDOOR FAN INSTANT OFF
OFF
FAN 60 SECOND DELAY OFF
14
BOARD FUNCTION

SECURE OWNER'S APPROVAL

When the system is functioning properly, secure the owner's
approval. Show the owner the location of all disconnect
switches and the thermostat. Teach the owner how to start
and stop the unit and how to adjust temperature settings
within the limitations of the system.

MAINTENANCE

NORMAL MAINTENANCE

Prior to any of the following maintenance proce-
dures, shut off all power to the unit, to avoid per-
sonal injury.
Periodic maintenance consists of changing or cleaning filters
and general cleaning of the outdoor coil.
FILTERS - Inspect once a month. Replace Disposable or
clean Permanent Type as necessary. DO NOT replace Per-
manent Type with Disposable.
MOTORS - Indoor and outdoor fan motors are permanently
lubricated and require no maintenance.
OUTDOOR COIL - Dirt should not be allowed to accumulate
on the outdoor coil surface or other parts in the air circuit.
Cleaning should be as often as necessary to keep the coil
clean. Use a brush, vacuum cleaner attachment, or other
suitable means. If water is used to clean the coil, be sure that
the power to the unit is shut off prior to cleaning.
Exercise care when cleaning the coil so that the coil
fins are not damaged.
Do not permit the hot condenser air discharge to be
obstructed by overhanging structures or shrubs.

173858-YIM-A-0306

Unitary Products Group