York 1-1/2 THRU 5 TON (10 SEER), D1EB018 THRU 060 Sequence Of Operation, Cooling, Heating

035-16703-001-A-0202

	SEQUENCE OF OPERATION
Cooling	Heating

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 energize 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 energize contactor “M1", and power will be supplied to the compres- sor and outdoor fan motor. If the fan switch on the thermo- stat is on the ”AUTO" position, the thermostat will also send a 24 volt signal to “G” on the fan control board and the in- door 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” posi- tion, 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 13 - THERMOSTAT SIGNALS (SINGLE PHASE UNITS)

WITH POWER TO UNIT AND THERMOSTAT IN HEATING MODE.

1.If the fan switch on the thermostat is in the “ON” position, the 24 volts at “G” will energize the “K1" relay contacts, and energize the indoor blower motor. If the fan switch on the thermostat is in the ”AUTO" position, the blower will oper- ate only when there is a call for heating by the thermostat.

2.On a call for heating, the thermostat will send 24 volts to “W1" on the fan control board. The 24 volts signal will ener- gize relay ”K2" on the fan control board, and the first stage of electric heat will be energized.

3.When the heating demand is satisfied, the electric heat will be de-energized when the 24 volt “W1" and ”W2" signals are 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 “K1" relay will open and de-energize the indoor blower motor after the appropri- ate time delay.

Please refer to Table 13 and 14 for more information.

SIGNAL	STATE
“G”	ON
	OFF
“G”	ON
“Y”	OFF
	ON
“G”
“W1"
	OFF
	ON
“G”
“W1"
”W2"
	OFF

BOARD FUNCTION

FAN INSTANT ON

FAN INSTANT OFF

FAN INSTANT ON

COMPRESSOR AND OUTDOOR FAN INSTANT ON

COMPRESSOR AND OUTDOOR FAN INSTANT OFF FAN 60 SECOND DELAY OFF

FAN INSTANT ON1

HEATER BANK 1 ELEC. HEAT INSTANT ON

HEATER1BANK 1 ELEC. HEAT INSTANT OFF FAN 5 SECOND DELAY OFF

FAN INSTANT ON

HEATER BANK 1 ELEC. HEAT INSTANT ON

HEATER BANK 2 ELEC. HEAT 10 SECOND DELAY ON HEATER BANK 3 ELEC. HEAT 20 SECOND DELAY ON

HEATER BANK 1 ELEC. HEAT INSTANT OFF HEATER BANK 2 ELEC. HEAT 2SECOND DELAY ON HEATER BANK 3 ELEC. HEAT 1 SECOND DELAY ON FAN 62SECOND DELAY OFF

SIGNAL STATE

ON

“W1"

OFF

ON

”W2"

OFF

ON

“W1"

”W2"

OFF

BOARD FUNCTION1

FAN INSTANT ON

HEATER BANK 1 ELEC. HEAT INSTANT ON

HEATER BANK 1 ELEC. HEAT INSTANT OFF FAN 5 SECOND DELAY OFF

FAN INSTANT ON1

HEATER BANK 1 ELEC. HEAT SEC. DELAY OFF HEATER1BANK 2 ELEC. HEAT INSTANT ON

HEATER BANK 1 ELEC. HEAT 2SEC. DELAY OFF HEATER BANK 2 ELEC. HEAT INSTANT OFF FAN 5 SECOND DELAY OFF

FAN INSTANT ON

HEATER BANK 1 ELEC. HEAT INSTANT ON

HEATER BANK 2 ELEC. HEAT 10 SECOND DELAY ON HEATER BANK 3 ELEC. HEAT 20 SECOND DELAY ON

STAGE 1 ELEC. HEAT INSTANT OFF

HEATER BANK 2 ELEC. HEAT 2SECOND DELAY ON HEATER BANK 3 ELEC. HEAT 1 SECOND DELAY ON FAN 62SECOND DELAY OFF

Unitary Products Group 11