York MA installation manual Section X Maintenance, Lubrication, UIM-A-0806, Unitary Products Group

262675-UIM-A-0806

MA SERIES - Air Handler Control Wiring

Typical A/C - Cooling only Applications

THERMOSTAT		AIR HANDLER			1 - STAGE
			BOARD
				AIR CONDITIONING
	R		R
	G		G
	Y		Y / Y2		Y
	W1		Y1
	W2		W2
	C		W1			HUMIDISTAT *
			O
			HUM
			X / L
			COM		C

MA SERIES - Air Handler Control Wiring

Typical A/C with Electric Heat Applications

THERMOSTAT		AIR HANDLER			1 - STAGE
			BOARD
				AIR CONDITIONING
	R		R
	G		G
	Y		Y / Y2		Y
			Y1
	W2		W2
	W1		W1			HUMIDISTAT *
	C		O
			HUM
			X / L
			COM		C

FIGURE 10: Cooling Models with Electric Heat Wiring

1.“Y” Terminal on Air Handler Control Board must be connected for full CFM and applications requiring 60 second blower off delay for SEER enhancement.

2.Optional humidity switch - contacts open on humidity rise.

3.Remove HUM STAT Jumper on AH Control Board

4.MODE Jumper on AH control board should be set to A/C for air conditioners and HP for heat pumps.

5.To change quantity of heat during HP defrost cycle - Reverse connections at W1 & W2 on Air Handler Control Board

CONTROL WIRING - MA Series - Air Handler & New 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 11: Two-Stage Cooling Wiring

1.“Y” Terminal on Air Handler Control Board must be connected for full CFM and applications requiring 60 second blower off delay for SEER enhancement.

2.Optional humidity switch - contacts open on humidity rise.

3.Remove HUM STAT Jumper on AH Control Board

4.MODE Jumper on AH control board should be set to A/C for air conditioners and HP for heat pumps.

5.To change quantity of heat during HP defrost cycle - Reverse connections at W1 & W2 on Air Handler Control Board

SECTION X: MAINTENANCE

Filters must be cleaned or replaced when they become dirty. Inspect at least once per month. The frequency of cleaning depends upon the hours of operation and the local atmospheric conditions. Clean filters keep unit efficiency high.

LUBRICATION

The bearings of the blower motor are permanently lubricated.

Unitary Products Group 15