York D7CG 036, D7CG 048, D7CG 060, D2CG 072 Enthalpy Set Point Adjustment, Static Resistances

530.18-N8Y

NOTE: Install filters so that “Air Flow” arrows point toward the unit.

8.Install filter cover over the end of the hood with one screw (center of hood), securing filters into position.

CAUTION: When proceeding with Steps 9 and 10, extreme care must be exercised while turning both the set point and minimum position adjusting screws to prevent twisting them off.

9.The enthalpy set point for the dampers may now be set by selecting the desired set point from graph in Figure 7. For a single enthalpy economizer, carefully turn the set point

adjusting screw to the “A”, “B”, “C” or “D” setting corre- sponding to the lettered curve. For a dual enthalpy econo- mizer, carefully turn the set point adjusting screw fully clockwise past the “D” setting.

10.To check that the damper blades move smoothly without binding, carefully turn the minimum position adjusting screw fully clockwise and then energize and de-energize terminals “R” to “G”. With terminals “R” to “G” energized, turn the minimum position screw counterclockwise until the desired minimum position has been attained.

11.Replace the filter section access panel.

FIG. 7 - ENTHALPY SET POINT ADJUSTMENT

TABLE 4 - STATIC RESISTANCES

EXTERNAL STATIC PRESSURE DROP

					RESISTANCE, IWG
DESCRIPTION						CFM
	1000	1200	1400	1600	1800	2000	2200	2400	2600	2800	3000
Economizer1, 2	0.07	0.08	0.09	0.11	0.13	0.15	0.17	0.20	0.23	0.26	0.30
Bottom Duct Connections1	0.06	0.07	0.08	0.09	0.10	0.11	0.12	0.14	0.16	0.19	0.22

1Deduct these resistance values from the available external static pressure shown in the respective Blower Performance Table.

2The pressure thru 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

8 Unitary Products Group