Johnson Controls 16 SEER - CZF Section Viii AC Control Board Functionality, LOW Voltage Detection

562156-UIM-A-0610

NOTICE

On 5 Ton unit the outdoor fan motor is a permanent magnet DC brushless type. The motor requires a separate Electronic Control to operate. Do not attempt to replace this motor with a typical PSC type. Damage to Electronic Control may result.

3.If the coil needs to be cleaned, use clean water to wash dust, dirt, and debris from outdoor condensing coil.

5.The indoor coil and drain pan should be inspected and cleaned reg- ularly to prevent odors and assure proper drainage.

Do not connect manifold gauges unless trouble is suspected. Approximately 3/4 ounce of refrigerant will be lost each time a stan- dard manifold gauge is connected.

NOTICE

DO NOT use coil cleaners to clean outdoor condensing coil. clean- ers containing HF-, hydroxides, chlorides, and sulfates can greatly reduce the lifetime of the aluminum condensing coil.

4.Refer to the furnace or air handler instructions for filter and blower motor maintenance.

TABLE 1: R-410A Saturation Properties

IT IS UNLAWFUL TO KNOWINGLY VENT, RELEASE OR DIS- CHARGE REFRIGERANT INTO THE OPEN AIR DURING REPAIR, SERVICE, MAINTENANCE OR THE FINAL DISPOSAL OF THIS UNIT.

WHEN THE SYSTEM IS FUNCTIONING PROPERLY AND THE OWNER HAS BEEN FULLY INSTRUCTED, SECURE THE OWNER’S APPROVAL.

TEMP. °F	PRESSURE	TEMP. °F	PRESSURE	TEMP. °F	PRESSURE	TEMP. °F	PRESSURE	TEMP. °F	PRESSURE
	PSIG		PSIG		PSIG		PSIG		PSIG
45	129.70	60	169.60	75	217.40	90	274.10	105	340.50
46	132.20	61	172.60	76	220.90	91	278.20	106	345.30
47	134.60	62	175.50	77	224.40	92	282.30	107	350.10
48	137.10	63	178.50	78	228.00	93	286.50	108	355.00
49	139.60	64	181.60	79	231.60	94	290.80	109	360.00
50	142.20	65	184.60	80	235.30	95	295.10	110	365.00
51	144.80	66	187.70	81	239.00	96	299.40	111	370.00
52	147.40	67	190.90	82	242.70	97	303.80	112	375.10
53	150.10	68	194.10	83	246.50	98	308.20	113	380.20
54	152.80	69	197.30	84	250.30	99	312.70	114	385.40
55	155.50	70	200.60	85	254.10	100	317.20	115	390.70
56	158.20	71	203.90	86	258.00	101	321.80	116	396.00
57	161.00	72	207.20	87	262.00	102	326.40	117	401.30
58	163.90	73	210.60	88	266.00	103	331.00	118	406.70
59	166.70	74	214.00	89	270.00	104	335.70	119	412.20

SECTION VIII: AC CONTROL BOARD FUNCTIONALITY

ANIT-SHORT CYCLE DELAY

The control includes a five-minute anti-short cycle delay (ASCD) timer to prevent the compressor from short cycling after a power interruption or thermostat signal interruption. The ASCD timer is applied when the control is first powered from the indoor unit thermostat and immediately following the completion of a compressor run cycle. The compressor and the outdoor fan will not operate during the five minutes that the timer is active.

The ASCD timer can be bypassed by connecting the TEST terminals for three seconds while the thermostat is calling for compressor opera- tion (Y1 input signal energized).

LOW VOLTAGE DETECTION

The control monitors the transformer secondary (24 VAC) voltage and provides low voltage protection for the AC unit and its components. In particular, the control prevents contactor chatter during low voltage con- ditions. If the voltage drops below approximately 19 VAC, the control will continue to energize any relays that are already energized but will not energize any additional relays until the voltage level increases. If the voltage drops below approximately 16 VAC, the control will immedi- ately de-energize the relay outputs and will not energize any relays until the voltage level increases. The control will store and display the appro- priate fault codes when low voltage conditions occur.

TEST INPUT

The control includes a TEST input connector that can be used for vari- ous testing functions during installation and service. Table 2 summa- rizes the behavior of the control when the two TEST pins are connected.

12 Johnson Controls Unitary Products