Johnson Controls AV*(C) Series Control Wiring Using Communicating Controls, Humidity Switch Input

536636-UIM-D-1211

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CONTROL WIRING - Air Handler & UPG HP Systems

Two Stage H/P with York Guard VI Board & Copeland “Ultra Tech”

Conventional Application - Not Hot Heat Pump

		AIR HANDLER			2 - STAGE SCROLL
THERMOSTAT			BOARD		HEAT PUMP
	R		R			R
	G		G
	Y2					Y2
			Y / Y2			Y2 OUT
	Y1		Y1			Y1
			W2			W2 OUT
	E		W1			W1 OUT
	W					W
	O		O			O
			HUM	HUMIDISTAT *		BS
	X / L		X / L			X / L
	C		COM			C

FIGURE 13: Two-Stage Heat Pump Wiring

* Optional dehumidification humidistat switch contacts open on humidity rise.

NOTES:

1.“Y/Y2” Terminal on air handler control board must be connected for full CFM and applications requiring 60 second blower off delay for SEER enhancement.

2.Remove humidistat jumper on air handler control board.

3.For heat pump applications - set MODE jumper on air handler control board to the HP position.

4.To change quantity of heat during HP defrost cycle - reverse connections at W1 and W2 on air handler control board

CONTROL WIRING USING COMMUNICATING CONTROLS

Use the wiring diagram below to connect the air handler control, Com- municating Control (wall thermostat) and communicating outdoor unit. Be sure that all of the “A” terminals are connected together, all of the “B” terminals are connected together, all of the “GND” or “C” terminals are connected together and all of the “R” terminals are connected together. See Figure 13. When using a fully communicating system, the large screw terminals (C, G, R, etc.) on the air handler control are not used. The four small screw terminals in the terminal block on the end of the air handler control should be used.

Touch Screen		Air Handler		Air Conditioner/Heat Pump
Communicating		Communicating		Communicating Control
	Control	Control
	A+		A+		A+
	R		R		R
	C		C		C
	B-		B-		B-
			R
			G
			Y/Y2
			Y1
			W2
			W1
			O
			HUM
			X/L
			COM

FIGURE 14: Air Handler with Communicating AC or HP

HUMIDITY SWITCH INPUT

The air handler control is designed to work with a humidity control that closes when the humidity is below the set-point. The control is open when the humidity is above the set-point. This humidity control may be referred to as a humidistat or a dehumidistat.

The humidity switch controls both humidification and de-humidification operation of the control. The control provides humidification using the HUM OUT relay output and de-humidification by lowering the blower speed. This is accomplished using the de-humidification input of the motor for variable speed models. The humidity switch should be con- nected to the R and HUM terminals of the control. See Figures 11 and 12.

The 24 volt power supply is provided by an internally wired low voltage transformer which is standard on all models, However, if the unit is con- nected to a 208 volt power supply, the low voltage transformer must be rewired to the 208 volt tap. See the unit wiring label.

Field supplied low voltage wiring can exit the unit on the top right hand corner or the right hand side panel. Refer to Figure 3.

Remove desired knockout and pierce foil faced insulation to allow wir- ing to pass through. Use as small of a hole as possible to minimize air leakage.

Install a 7/8” plastic bushing in the selected hole and keep low voltage wiring as short as possible inside the control box.

To further minimize air leakage, seal the wiring entry point at the outside of the unit.

The field wiring is to be connected at the screw terminals of the control board. Refer to Figures 11 or 12.

NOTICE

All wiring must comply with local and national electrical code require- ments. Read and heed all unit caution labels.

NOTICE

It is possible to vary the amount of electric heat turned on during the defrost cycle of a heat pump. Standard wiring will only bring on the first stage of electric heat during defrost. See Heat Output and Limit Connections and Table 5 for additional information on heat during defrost cycle.

Johnson Controls Unitary Products 9