Honeywell W6215, W7215, W7460 Data Sheet

W6215, W7215, W7460 Economizer Logic Modules

FOR VENTILATION CONTROL

PRODUCT DATA

FEATURES

APPLICATION

W6215, W7215, and W7460 Economizer Logic Modules are used with an indoor sensor input (ISI), and solid state C7400 Enthalpy Sensors or C7650 Dry Bulb Temperature Sensors. All models proportion outdoor and return air dampers for control of free cooling in commercial HVAC equipment. The W7215B and W7460B are used with an outdoor sensor input (OSI) along with the ISI.

•Operates from the space thermostat and an ISI to provide a totally integrated control system.

•Solid state control package provides accuracy, reliability and stability.

•Housed in high-impact, glass-fiber reinforced plastic case.

•Mounts on sheet metal duct or remotely in a mechanical room. Mounting screws included.

•The W6215 and W7215 are used with Honeywell Series 62 and Series 72 actuators (respectively). The W7460 is used with Honeywell M7415 Damper Actuators.

•Combines minimum and maximum damper position potentiometers and compressor staging relay functions with solid state enthalpy or dry bulb changeover control this control can be tempered by ISI, and fan cycling.

•Outdoor Sensor input incorporated into logic of W7215B and W7460B models.

•Shutdown and Air Change can be used with all models.

•Purge cycling can be used with the W6215A, W7215A and W7460A models.

•Terminals included for connecting optional S963B1128 Remote Potentiometers for remote minimum and maximum damper position control.

•LED and relay terminals indicate when free cooling is available.

•LED indicates when module is in ISI mode.

	Contents
Application ........................................................................	1
Features ...........................................................................	1
Specifications ...................................................................	2
Ordering Information ........................................................	2
Installation ........................................................................	3
Operation ..........................................................................	5
Settings and Adjustments .................................................	6
Checkout and Troubleshooting .........................................	26

® U.S. Registered Trademark
Copyright © 2001 Honeywell • All Rights Reserved	63-2544-3

W6215, W7215, W7460 ECONOMIZER LOGIC MODULES

SPECIFICATIONS

Models: See Table 1.

Dimensions: See Fig. 1.

Electrical Ratings:

Input Voltage: 24 Vac +20%, -15%; 50/60 Hz (Class 2). Nominal Power Consumption (at 24 Vac, 60 Hz):

W6215A: 12.5 VA. W7215A, W7460A: 10 VA. W7215B, W7460B: 10.5 VA.

Relay Contact Rating at 30 Vac (maximum power from class 2 input only): 1.5A run, 3.5A inrush.

Ambient Ratings:

Temperature:

Operating Ambient: -25°F to +125°F (-32°C to +52°C). Shipping: -25°F to +125°F (-32°C to +52°C).

Humidity (Noncondensing): 5 to 95 percent rh.

Inputs:

Enthalpy (C7400): 2-wire (18,20,22 AWG) connection. Dry Bulb Temperature (C7650): 2-wire (18,20,22 AWG)

connection.

Discharge Air (C7046): 2-wire (18,20,22 AWG) connection. Mixed Air (C7150): 2-wire (18,20,22 AWG) connection. Indoor Sensor: 2-10 Vdc control signal.

Outdoor Sensor (W7215B and W7460B only): 2-10 Vdc control signal.

Outputs:

W7215: 2-10 Vdc.

W6215: Series 62 (Open/Close/Hold).

24 Vac out (W7215, W6215 only): 25 VA maximum.

Accessories:

32004783-001 Weather Shield Economizers.

4074EJM Bag Assembly. Consists of: Checkout jumper, 620 ohm, 1.2K ohm, 5.6K ohm, and 6.8K ohm checkout

resistors, and 536 ohm, 665 ohm, and 3480 ohm resistors for use with Honeywell Series 90 Actuators.

C7046A Discharge Air Temperature Sensor. C7150B Mixed Air Temperature Sensor. C7400 Solid State Enthalpy Sensor.

C7650 Dry Bulb Temperature Sensor.

S963B1128 Remote Potentiometer to provide remote control of damper minimum or maximum position.

ST6008 Energy Management Timer for occupied/unoccupied control.

Approvals:

Underwriters Laboratories Inc. listed: Meets UL873 plenum requirements.

		3/4 (19)
						1
						(25)
24VAC		24VAC			TR1
		TR Hot
Hot					Com
		B		C
24VAC		A		D	+
Com
				So
				Sr	+
					5
				1
					2
+		Maximum3			4
		Position
2-10V				T	T1
		Open
OUT	<![if ! IE]> <![endif]>W7215A					8-5/8
				P
–					P1	(219)
		Free Cool
		Mininum
		Position
Free				Q
					Q1
Cool
		Closed
				AQ
			6	+	AQ1
		2		10	–
Unit			ISI
				SD	SD1
Control		Set Pt
Exhaust				AC	AC1
Fan
			ISI
Indoor				PC	PC1
			50%
Fan
		0%		100%
		Exhaust
		Set Pt

Exhaust

5-3/4 (146)

1

(25) 1-9/16

(40)

M11788A

Fig. 1. W6215,W7215,W7460 dimensions in in. (mm). [W7215A shown]

ORDERING INFORMATION

When purchasing replacement and modernization products from your TRADELINE® wholesaler or distributor, refer to the TRADELINE® Catalog or price sheets for complete ordering number.

If you have additional questions, need further information, or would like to comment on our products or services, please write or phone:

1.Your local Home and Building Control Sales Office (check white pages of your phone directory).

2.Home and Building Control Customer Relations Honeywell, 1885 Douglas Drive North Minneapolis, Minnesota 55422-4386

In Canada—Honeywell Limited/Honeywell Limitée, 35 Dynamic Drive, Scarborough, Ontario M1V 4Z9.

International Sales and Service Offices in all principal cities of the world. Manufacturing in Australia, Canada, Finland, France, Germany, Japan, Mexico, Netherlands, Spain, Taiwan, United Kingdom, U.S.A.

63-2544—3

2

W6215, W7215, W7460 ECONOMIZER LOGIC MODULES

Table 1. W6215, W7215, and W7460 Economizer Models.

	For Use	Discharge Air	Outdoor Sensor	Exhaust
Model	with Actuator	Temperature Input	Input (OSI) Setpoint	Fan Setpoint	Purge
W6215A	Honeywell Series 62	C7150B or C7046A Sensor	No	Adjustable	Yes
W7215A	Honeywell Series 72	C7150B or C7046A Sensor	No	Adjustable	Yes
W7215B	Honeywell Series 72	C7150B or C7046A Sensor	Yes	Fixed	No
W7460A	Honeywell M7415	C7150B or C7046A Sensor	No	Adjustable	Yes
W7460B	Honeywell M7415	C7150B or C7046A Sensor	Yes	Fixed	No

NOTE: All models include minimum and maximum position potentiometers, setpoint for enthalpy or dry-bulb, and ISI setpoint.

INSTALLATION

When Installing this Product...

1.Read these instructions carefully. Failure to follow them could damage the product or cause a hazardous condition.

2.Check the ratings given in the instructions and on the product to make sure the product is suitable for your application.

3.Installer must be a trained, experienced service technician.

4.After installation is complete, check out product operation as provided in these instructions.

CAUTION

Electrical Shock or Equipment Damage Hazard. Can shock individuals or short equipment circuitry.

Disconnect power supply before installation.

IMPORTANT

All wiring must agree with applicable codes, ordinances and regulations.

Location and Mounting

W6215, W7215, W7460 Economizer Logic Module

W6215, W7215, and W7460 Logic Modules mount directly on a sheet metal duct or panel. When planning the installation, allow enough clearance for maintenance and service. Mount device in a location protected from rain, snow, and direct sunlight. Secure device to sheet metal using the three supplied mounting screws, see Fig. 2.

NOTE: See Fig. 3 for representative locations of connected system devices.

C7400 Enthalpy Sensor and

C7650 Dry Bulb Temperature Sensor

W6215,W7215,W7460 Logic Modules accept signals from either the C7400 Enthalpy Sensor or the C7650 Dry Bulb Temperature Sensor. The wiring is the same for either sensor.

IMPORTANT

When using differential sensing, both sensors must be of the same type (enthalpy or dry bulb).

OUTDOOR AIR SENSING

1.Mount sensor in any orientation that exposes it to freely circulating air and protects it from rain, snow, and direct sunlight.

2.Connect it to the SO and + terminals of the device.

RETURN AIR SENSING

1.Ensure differential enthalpy control has a second sensor in the return air duct.

2.Connect this sensor to the SR and + terminals of the W6215, W7215, or W7460.

<![if ! IE]>

<![endif]>W6210 A 1003

M11790

Fig. 2. Mounting W6215, W7215, W7460 on sheet metal.

Indoor Sensor Input

The ISI can be any sensor that provides a 2-10 Vdc output. The ISI modulates the outdoor damper to provide ventilation based on occupancy. The designer determines contaminants to monitor, selects appropriate sensor, determines the sensor threshold, and adjusts the ISI potentiometer accordingly. The ISI LED lights when the ISI signal is above setpoint. Mount the sensor according to the manufacturer specifications. If not available, use the following guidelines:

1.Mount sensor in an area with unobstructed air circulation.

2.Connect it to the AQ and AQ1 terminals of the W6215, W7215, or W7460 (see Wiring section for details).

3.Adjust the ISI potentiometer setpoint to correspond to ISI voltage output at the threshold.

IMPORTANT

Ensure proper polarity of sensor connections. Incorrect polarity negates the sensor signal.

3

63-2544—3

W6215, W7215, W7460 ECONOMIZER LOGIC MODULES

Outdoor Sensor Input (W7215B and W7460B only)

The OSI sensor can be any sensor that provides a 2-10 Vdc output. Mount the sensor according to the manufacturer specifications. If not available, use the following guidelines:

1.Mount sensor in an area with unobstructed air circulation that is protected from rain, snow, and direct sunlight.

IMPORTANT

Ensure proper polarity of sensor connections. Incorrect polarity negates the sensor signal.

2.Connect it to the OA and OA1 terminals of the W7215B, or W7460B (see Wiring section for details).

3.Adjust the OSI potentiometer setpoint to correspond to OSI sensor voltage output at the threshold.

DISCHARGE

SPACE

AIR SENSOR

DIRECT

THERMOSTAT

INDOOR

2

C7046A

AIR

EXPANSION

SENSOR

COIL

W6215,

C7150B

2

W7215,

ENTHALPY

OR

1

C7400

SENSOR

W7460

MIXED AIR

SENSOR

INDOOR

OUTDOOR

FAN

SERIES

DISCHARGE

AIR

62 OR 72

SENSOR

AIR

ACTUATOR

OUTDOOR

AIR

1

C7400

ENTHALPY

SENSOR

1 FOR DIFFERENTIAL ENTHALPY, THE TWO C7400

ENTHALPY SENSORS ARE CONNECTED TO THE

W6215/W7215/W7460 ECONOMIZER CONTROL—ONE

EXHAUST

IS MOUNTED IN RETURN AIR, AND THE OTHER IS

FAN

MOUNTED IN OUTDOOR AIR. DIFFERENTIAL

ENTHALPY CONTROL PROVIDES GREATER

ENERGY SAVINGS THAN SINGLE ENTHALPY.

2 USE EITHER MIXED AIR SENSOR OR DISCHARGE

RETURN AIR

EXHAUST AIR

M11816

AIR SENSOR, NOT BOTH.

Fig. 3. Representative locations of connected Economizer system devices.

Wiring

CAUTION

Electrical Shock or Equipment Damage Hazard. Can shock individuals or short equipment circuitry.

Disconnect power supply before installation.

IMPORTANT

1.All wiring must comply with applicable local codes, ordinances and regulations.

2.Refer to Fig. 6 through 25 for typical wiring diagrams.

3.Refer to Table 2 for a list of the wiring diagrams and corresponding Figure numbers in this document.

4.All device inputs and outputs must be 24 Vac Class 2.

NOTE: All connections with label designation ending in 1 (examples: TR1, T1, P1, Q1, AQ1) are ac/dc common connections.

Optional Applications

Remote Minimum Position Control

Remote control of outdoor air dampers is desirable when requiring temporary additional ventilation. One potentiometer controls the damper minimum position, another potentiometer controls the damper maximum position. The addition of S963B1128 Remote Potentiometers allows occupants to open or close the dampers beyond minimum position for modified ventilation. Connect the potentiometers as shown in Fig. 4.

IMPORTANT

The minimum position signal takes priority to the maximum position signal. With the maximum set below the minimum, the logic module signals the actuator to maintain the minimum position.

Free Cool Timing

The Free Cool contacts close while the logic module operates free cooling. Connecting a timer to these contacts allows tracking of the free cooling usage time.

63-2544—3

4

W6215, W7215, W7460 ECONOMIZER LOGIC MODULES

Table 2. Applicable Wiring Diagrams.

Logic Module	Actuator	Enthalpy Changeover	Figure	Comments
W6215A	Honeywell Series 62	Single	8	Single-stage cooling system.
		Single or Differential	9	Two-stage cooling system.
W7215A	Honeywell Series 72	Single	10	Single-stage cooling system.
		Single or Differential	11	Two-stage cooling system.
			12	T775 controller.
	Honeywell Series 90	n/a	6	Add Q7230 Interface Module.
W7215B	Honeywell Series 72	Single	13	Single-stage cooling system.
		Single or Differential	14	Two-stage cooling system.
			15	T775 controller.
W7460A	Honeywell M7415	Single	16	Single-stage cooling system.
		Single or Differential	17	Two-stage cooling system.
W7460B	Honeywell M7415	Single	18	Single-stage cooling system.
		Single or Differential	19	Two-stage cooling system.
ALL	n/a	n/a	20	W7100 controller.
			25	W973 Logic Panel.
			4	S963 remote damper control.
Parallel Wiring
W6215	Honeywell Series 62	Single or Differential	21	Honeywell Series 62 Direct Coupled Actuators.
W7215A	Honeywell Series 72		22	Honeywell Series 72 Direct Coupled Actuators.
			23	Honeywell Series 72 Modutrol Motors.
	Honeywell M7415		24	M7415 Motors.

OPERATION

The purpose of the economizer is to use outdoor air for cooling, whenever possible, to reduce compressor operation.

When wired as shown in Fig. 6 through 25, the logic module responds to the cooling thermostat signal. This system uses C7400 Solid State Enthalpy Changeover Sensor(s) or

C7650 Dry Bulb Temperature Sensor(s). The C7400 responds to both dry bulb temperature and humidity, allowing use of outdoor air at higher temperatures for free cooling when humidity is low. The C7650 responds only to dry bulb temperature; use only in dry, arid climates.

The logic module functions as a true first stage of cooling providing maximum fuel economy during the cooling cycle. It automatically locks out free cooling during heating; holding the outdoor air damper at the minimum position setting.

The logic module can operate as either a basic free cooling controller, or it can incorporate additional functions. Tables 3 and 5 detail the input/output (I/O) logic of the module. Certain functions—Purge, Shutdown, and Air Change—override others, see Table 3. When these functions are all off, the logic module energizes the Unit Control and Indoor Fan contacts, operating according to Table 5.

Purge (W6215A, W7215A, and W7460A only)

When terminals PG and PG1 connect through relay contacts or a jumper:

1.Outdoor damper drives fully closed.

2.Exhaust fan turns on.

			S963B1128 REMOTE
	OPEN		POTENTIOMETER
	MINIMUM		R	CW
			CCW
	POSITION		OPEN	CLOSE
	ADJUSTMENT	P
			P1	W
			B
	CW		135 OHM
	MAXIMUM		S963B1128 REMOTE
	POSITION		POTENTIOMETER
	ADJUSTMENT	Q	Q1
			R	CW
			CCW
	CW		OPEN	CLOSE
			B	W
			135 OHM	M11796A
	W6215/W7215/W7460 ECONOMIZER

Fig. 4. S963B1128 Remote Potentiometer used with W6215, W7215, W7460 for remote damper control.

5

63-2544—3

W6215, W7215, W7460 ECONOMIZER LOGIC MODULES

Table 3. W6215, W7215, W7460 Economizer Purge,

Shutdown, and Air Change I/O Logic.

	INPUTS			OUTPUTS
Purgea	Shut-	Air	Damper	Unit	Indoor	Exhaust
	down	Change		Control	Fan
On	-	-	Fully Closed	Off	Off	On
Off	On	-				Off
	Off	On	Fully Open		On	On

a Purge present only on W6215A, W7215A, and W7460A.

Shutdown

One contact closure shuts down all systems. When terminals SD and SD1 connect through relay contacts or a jumper:

1.Outdoor damper drives fully closed.

2.Exhaust fan turns off.

3.Indoor fan turns off.

Air Change

When terminals AC and AC1 connect through relay contacts or a jumper:

1.Outdoor damper drives fully open.

2.Exhaust fan turns on.

3.Indoor fan turns on.

NOTE: With Purge, Shutdown, and Air Change deenergized, Exhaust will be de-energized unless the signal exceeds the exhaust fan setpoint; other logic module functions remain unaltered.

SETTINGS AND ADJUSTMENTS

Potentiometers with screwdriver adjustment slots, located on the device face, provide adjustments for several parameters (see Fig. 5 for locations on device):

—ISI setpoint.

—OSI setpoint (W7215B and W7460B only).

—Minimum damper position.

—Maximum damper position.

—Enthalpy changeover.

—Exhaust setpoint (W6215A, W7215A and W7460A only).

Indoor Sensor Input Setpoint

The logic module modulates the outdoor damper to provide ventilation based on the 2-10 Vdc ISI. With no cooling signal, the ISI overrides the outdoor air damper when ventilation requires outdoor air.

Outdoor Sensor Input Setpoint (W7215B and W7460B only)

The OSI logic operates from a 2-10 Vdc sensor signal. The operation of these logic modules is slightly different from the other models, see Table 4.

Table 4. W7215B and W7460B OSI Operation.

OSI		ISI		Actuator	OSI LED	Alarm
Below set		Below set		Modulatesa	Off	Off
		Above set		Modulatesb
				Modulatesc
Above set		Below set		Fully closed	On	Off
		Above set		Modulatesd	On	On

a Modulation based on signal from mixed air sensor.

bWith ISI signal greater than mixed air sensor signal: Modulation, based on ISI signal, between minimum and maximum positions.

cWith ISI signal less than mixed air sensor signal: Modulation, based on mixed air sensor signal, between: M7215B: Minimum and full open positions

M7460B: Minimum and maximum positions.

dModulation based on mixed air sensor signal; Alarm terminals connect to energize warning light, audio alarm, or air cleaner.

Table 5. W6215, W7215, W7460 Economizer I/O Logic.

	INPUTS					OUTPUTS
	Enthalpya						Compressor
ISI			Y1b	Y2b
	Outdoor	Return				Damper	1	2
Below set	High (Free Cooling LED Off)	Low	On	On		Minimum position	On	On
(ISI LED Off)
			On	Off			On	Off
	Low (Free Cooling LED On)	High	On	On		Modulatingc	On	Off
			On	Off			Off	Off
Above set	High (Free Cooling LED Off)	Low	On	On		Modulatingd	On	On
(ISI LED On)
			On	Off			On	Off
	Low (Free Cooling LED On)	High	On	On		Modulatinge	On	Off
			On	Off			Off	Off
a For single enthalpy control, the module compares outdoor enthalpy to the ABCD setpoint.
b If both stages of cooling are off, the system is off and the damper is at:			• Minimum position if ISI is below setpoint.
			• Modulating if ISI is above setpoint.

cW6215, W7460: Modulation, based on the mixed air sensor signal, between minimum and maximum positions. W7215: Modulation, based on the mixed air sensor signal, between minimum and full-open positions.

d Modulation, based on the ISI, between minimum and maximum positions.

eModulation, based on the greater of ISI and mixed air sensor signals, between minimum and either maximum position (ISI) or fully open (mixed air signal).

NOTE: Each sensor has it’s own setpoint for threshold and LED indication.

63-2544—3

6

W6215, W7215, W7460 ECONOMIZER LOGIC MODULES

ENTHALPY

CHANGEOVER

SETPOINT

24VAC		24VAC			TR1
		TR Hot
Hot					Com
		B		C
24VAC		A		D	+
Com
				So
					+	MINIMUM
				Sr		DAMPER
					5	POSITION
						SETTING
				1
					2	LED LIGHTS
+		Mininum3			4	WHEN
		Position				OUTDOOR
2-10V				T	T1	AIR IS
		Open				SUITABLE
OUT	<![if ! IE]> <![endif]>W7215A
–				P	P1	FOR FREE
						COOLING
		Free Cool
		Maximum				MAXIMUM
		Position
Free				Q		DAMPER
					Q1
Cool						POSITION
		Closed
						SETTING
			6	AQ	AQ1
				+
		2		Q	–	INDOOR AIR
Unit			ISI	10
				SD	SD1	SENSOR
Control		Set Pt
Exhaust				AC		SETPOINT
					AC1
				Q
Fan			ISI			LED LIGHTS
				PG
Indoor					PG1	WHEN INDOOR
			50%
Fan						SENSOR INPUT
				Q
		0%				IS ABOVE
				100%
		Exhaust				SETPOINT
		Set Pt
		Exhaust				EXHAUST
						FAN
						SETPOINT
LED LIGHTS WHEN EXHAUST IS ON						M11787A

Fig. 5. Potentiometer and LED locations.

Adjusting Minimum and Maximum Positions

The minimum position potentiometer maintains the minimum outdoor air flow into the building during occupied period. The maximum position potentiometer allows the installer to limit the amount of outdoor air flow into the building, when the ISI overrides the mixed air sensor. Setting the maximum position of the damper prevents the introduction of large amounts of hot or cold air into the space.

IMPORTANT

With the maximum position set below the minimum position, the minimum position overrides the maximum position (negating most functions of the logic module, as the damper cannot move).

NOTES:

—When the mixed air sensor takes control, it overrides the maximum position potentiometer.

—If mixed air temperature drops to 40°F, the mixed air sensor overrides the ISI and closes the damper to minimum position to protect from freezing the hot or chilled water coils. Control returns to normal once the mixed air temperature rises to 43°F.

Minimum Position Adjustment

For detailed assistance in minimum position selection reference the Economizer Application Guide (form 63-8594) Ventilation section. The following provides basic guidelines for minimum position selection and adjustment:

IMPORTANT

Adjust the minimum position potentiometer to allow the minimum amount of outdoor air, as required by local codes, to enter the building.

NOTE: Make minimum position adjustments with at least a 10°F [6°C] temperature difference between outdoor and return air.

1.Calculate the appropriate mixed air temperature, see Equation 1.

2.Disconnect mixed air sensor from terminals T and T1.

3.Ensure that either the factory-installed jumper is in place across terminals P and P1 or, of remote damper position is required, that it is wired according to Fig. 4 and turned fully clockwise.

4.Connect 24 Vac across terminals TR and TR1.

5.Carefully adjust the potentiometer on the face of the device with a small screwdriver until the mixed air temperature reaches the calculated value.

NOTE: Ensure that the sensed air is well mixed.

Equation 1. Formula to aid in minimum position adjustment.

( TO × OA) + ( TR × RA) = TM

Where:

TO = Outdoor air temperature OA = Percent of outdoor air TR = Return air temperature RA = Percent of return air

TM = Resulting mixed air temperature

IMPORTANT

This procedure requires use of a quality thermometer capable of reading to 0.5°F [0.25°C].

NOTE: The following sample calculation uses only Fahrenheit temperature.

EXAMPLE: Assume local codes require 10% outdoor air during occupied conditions, outdoor air is 60°F and return air is 75°F. Under these conditions, what is the temperature of the mixed air?

( 0.1 × 60°F) + ( 0.9 × 75°F) = 6.0°F + 67.5°F = 73.5°F

Mixed air will be 73.5°F when OA is 60°F and RA is 75°F with 10 percent outdoor air entering the building.

Maximum Position Adjustment

1.Disconnect mixed air sensor from terminals T and T1 and short terminals T and T1.

2.Make sure either the factory-installed jumper is in place across terminals Q and Q1 or, if remote damper position is required, that it is wired according to Fig. 4 and turned fully clockwise.

3.Connect 24 Vac across terminals TR and TR1.

4.Adjust the potentiometer on the face of the device with a screwdriver for desired maximum position.

Enthalpy Changeover

Outdoor Enthalpy Changeover Setpoint

The outdoor enthalpy changeover setpoint returns the outdoor air damper to minimum position when enthalpy rises above its setpoint. Enthalpy setpoint scale markings, located in the device, are A, B, C, and D. See Fig. 7 for the corresponding control point. The factory-installed 620-ohm jumper must be in place across terminals SR and +.

7

63-2544—3

W6215, W7215, W7460 ECONOMIZER LOGIC MODULES

Differential Enthalpy Changeover Setting

Differential enthalpy control uses two C7400 Enthalpy Sensors connected to one logic module. The logic module compares outdoor air to return air instead of to a setpoint as it does for single enthalpy. Turn the setpoint potentiometer fully clockwise to the D setting. The logic module selects the lower enthalpy air (return or outdoor) for cooling; for example, when outdoor air has lower enthalpy than return air, the outdoor air damper opens to bring in outdoor air for free cooling.

Exhaust Setpoint

Except for Purge, Shutdown, and Air Change, the exhaust setpoint determines when the exhaust fan runs based on the damper position. When the ISI call for exhaust comes, the module provides a 45 ±15 second delay before exhaust fan activation. This delay allows the damper to reach the appropriate position to avoid unnecessary fan overload.

Fixed Exhaust Setpoint (W7215B and W7460B)

The W7215B and W7460B Logic Modules have a fixed exhaust setpoint. The logic module uses an exhaust setpoint of 60 percent. When the damper reaches 60 percent open (from fully closed), the logic module calls for exhaust.

			W7215A
HONEYWELL			24 VAC HOT
			TR	TR1
SERIES 90
			24 VAC COM
ACTUATOR
		3480
(ML9175,		Ohms	+
ML9185,	W
M9175,		536	2-10V
M9185)	R
		Ohms	OUT
	B	1	–
		665
		Ohms

Adjustable Exhaust Setpoint (W6215A, W7215A, and W7460A only)

The W6215A, W7215A, and W7460A Logic Modules have an adjustable setpoint. This potentiometer allows the installer to set the exhaust setpoint at an actual damper position percentage open from fully closed.

1USE 1/2 WATT, 1% RESISTORS OF SPECIFIED OHM RATINGS (INCLUDED IN 4074EJM RESISTOR KIT). FOR

MOD IV MOTORS, THE Q7230 MODULE CAN REPLACE THE RESISTORS.

M11903A

Fig. 6. W7215A used with Honeywell Series 90 Actuator.

CONTROL

CURVE

A

B

C

D

18 16 14 12

CONTROL POINT
APPROX. °F (°C)
AT 50% RH
73 (23)
70 (21)
67 (19)									DRY
63 (17)
								POUND
							PER	34
					BTU			32
				—			30
	ENTHALPY				28
26
24
22
20
								55
								(13)
								50
							(10) C
						45 D
40					(7)
(4)
35
(2)

	AIR	40
		38
	36

65

(18)

60

(16)

A

B

44 42

70

(21)

100

90

	85	90	95	100		105	110
	(29)	(32)	(35)	(38)		(41)	(43)
	46
	80
	(27)
			HUMIDITY		(%)
	75
(24)
		RELATIVE
80	70
	60
	50
	40
		30
				20
							10

D C B A

35

40

45

50

55

60

65

70

75

80

85

90

95

100

105

110

(2)(4) (7) (10) (13) (16) (18) (21) (24) (27) (29) (32) (35) (38) (41) (43)

APPROXIMATE DRY BULB TEMPERATURE—°F (°C)	M11806

Fig. 7. W6215, W7210, and W7460/C7400 performance characteristics for enthalpy changeover settings.

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8

W6215, W7215, W7460 ECONOMIZER LOGIC MODULES

			W6215A
HONEYWELL		24 VAC HOT
					TR1
SERIES 62		24 VAC COM		TR
ACTUATOR
							+	C7400
(ML6275,		CLOSE		SO	+			OUTDOOR
ML6285,								AIR
M6275,		OPEN					S	ENTHALPY
M6285)					+			SENSOR
				SR		620 OHM
						RESISTOR
					5	6	9
			1K	1	2
			1S
		4	2K	3	4		9
		OPEN				C7150B MIXED
					T1	AIR OR
500 OHM		WIPER		T		C7046A
			1S1			DISCHARGE
		CLOSED		P	P1	AIR SENSOR
		MINIMUM POSITION
	5	ADJUSTMENT
		FREE	MAXIMUM	Q	Q1
		COOL	POSITION
			ADJUSTMENT	AQ		2-10 VDC
					AQ1
						INDOOR AIR
		UNIT				+ SENSOR
				SD	SD1	SHUT DOWN		8
		CONTROL						UNOCCUPIED
		EXHAUST		AC	AC1	AIR CHANGE	ST6008
		FAN					TIMER
		INDOOR		PG	PG1	PURGE		OCCUPIED
		FAN
							C
Y1		W	T6031 AMBIENT				Y1	COOL 1
			LOCKOUT
Y2		R	CONTROL
			50 F SETPOINT
W2							W2	HEAT 2
W1							W1	HEAT 1
G								FAN
								DELAY
								RELAY
RH							FDR
							G	FAN	3
RC
							FDR		L2
7								2
									1
							R
X									L1
									(HOT)

T7300 OR T874

THERMOSTAT

1POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.

2ACTUATOR SPRING-RETURNS CLOSED WHEN FAN IS NOT RUNNING.

3ENSURE THAT TRANSFORMER IS SIZED TO HANDLE THE EXTRA LOAD OF THE ECONOMIZER AND ACTUATOR.

41S IS AN ELECTRONIC SWITCH THAT CLOSES WHEN POWERED BY A 24 VAC INPUT.

5THE COMMON FOR THE W6215A IS DIFFERENT THAN THE COMMON (WIPER) FOR THE SERIES 62 ACTUATORS. BE SURE TO CONNECT EACH TO A DIFFERENT CIRCUIT.

HVAC EQUIPMENT

TERMINAL STRIP

6FACTORY INSTALLED 620 OHM, 1 WATT, 5% RESISTOR SHOULD NOT BE REMOVED. DIFFERENTIAL ENTHALPY NOT RECOMMENDED FOR USE WITH SINGLE-STAGE COOLING SYSTEMS OR SINGLE-STAGE COOLING THERMOSTATS.

7FOR T7300 ONLY.

8FOR T7300, USE CONTACTS A1 AND A2 INSTEAD OF THE TIMER.

9FOR TWO-STAGE THERMOSTATS ONLY.

M11803A

Fig. 8. W6215A used in single-stage cooling system with single enthalpy changeover and Honeywell Series 62 Actuator.

9

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