York DJ150 Operation, Additional Static Resistance, Motor Sheave Datum Diameters, Cooling Only

035-19046-002-B-0104

TABLE 20: ADDITIONAL STATIC RESISTANCE

CFM	Cooling Only*	Economizer† ‡		Electric Heat KW†
			18	24	36	54
3700	0.20	0.04	0.18	0.21	0.22	0.26
3900	0.23	0.04	0.20	0.23	0.24	0.28
4100	0.25	0.04	0.22	0.25	0.26	0.31
4300	0.28	0.05	0.24	0.28	0.29	0.34
4500	0.30	0.05	0.26	0.30	0.31	0.37
4700	0.33	0.05	0.29	0.33	0.34	0.40
4900	0.36	0.05	0.31	0.35	0.37	0.43
5100	0.39	0.06	0.34	0.38	0.40	0.46
5300	0.42	0.06	0.37	0.41	0.43	0.49
5500	0.45	0.06	0.40	0.44	0.46	0.53
5700	0.48	0.06	0.43	0.47	0.49	0.56
5900	0.52	0.07	0.46	0.50	0.53	0.59
6100	0.56	0.07	0.49	0.53	0.56	0.62
6300	0.60	0.07	0.53	0.56	0.59	0.65

*. Add these resistance values to the available static resistance in the respective Blower Performance Tables.

†.Deduct these resistance values from the available external static pressure shown in the respective Blower Performance Table.

‡.The pressure drop through the economizer is greater for 100% outdoor air than for 100% return air. If the resistance of the return air duct system is less than 0.25 IWG, the unit will deliver less CFM during full economizer operation.

TABLE 21: MOTOR SHEAVE DATUM DIAMETERS

	1VM50x7/8		1VP56x1-1/8
(3 HP Motor)			(5 HP Motor)
Turns Open		Datum	Turns Open	Datum
		Diameter		Diameter
0		4.4	1	5.3
1/2		4.3	1-1/2	5.2
1		4.2	2	5.1
1-1/2		4.1	2-1/2	5.0
2		4.0	3	4.9
2-1/2		3.9	3-1/2	4.8
3		3.8	4	4.7
3-1/2		3.7	4-1/2	4.6
4		3.6	5	4.5
4-1/2		3.5	5-1/2	4.4
5		3.4	6	4.3

For gas heating, the UCB monitors the "W1" call but does not handle the operation of the gas furnace. An ignition control board controls the gas heater operation. For electric heat units, the UCB passes the call to the electric heater. In both cases, when the "W1" call is sensed, the indoor air blower is energized following a specified heating delay.

If at any time a call for both heating and cooling are present, the heating operation will be performed. If operating, the cool- ing system is halted as with a completion of a call for cooling. Heating always takes priority.

COOLING SEQUENCE OF OPERATION

CONTINUOUS BLOWER

By setting the room thermostat fan switch to "ON," the supply air blower will operate continuously.

INTERMITTENT BLOWER

OPERATION

SEQUENCE OF OPERATIONS OVERVIEW

For the Predator Magnum series of units, the thermostat makes a circuit between "R" and "Y1" for the first stage of cooling.

The call is passed to the unit control board (UCB), which then determines whether the requested operation is available and, if so, which components to energize.

With the room thermostat fan switch set to "AUTO" and the system switch set to either the "AUTO" or "HEAT" settings, the blower is energized whenever a cooling or heating opera- tion is requested. The blower is energized after any specified delay associated with the operation.

When energized, the indoor blower has a minimum run time of 30 seconds. Additionally, the indoor blower has a delay of 10 seconds between operations.

Unitary Products Group 33