White Rodgers CZ-4 User manual

FORM 2045-2 1306 ©2013 White-Rodgers by Permission 37-6864B
Model CZ-4
Installation and Operating Instructions

FORM 2045-2 1306 ©2013 White-Rodgers by Permission 37-6864B
1
CZ-4 ZONING SYSTEM FEATURES
Table of Contents
Installation 2
Operation 2-3
Set-Up for Various
HVAC Equipment 3
Leaving Air Sensor 3-4
Timers 4
ZoneAdder 4
Checkout 4
Wiring 4-5
Troubleshooting 5
Wiring Diagram 6
INSTALLATION
The CZ-4 is a four (4) zone control panel that controls up to four
zones of heating and cooling. The CZ-4 panel is the central control
panel that all zone dampers, zone thermostats, HVAC Equipment,
power transformer, Leaving Air Sensor and ZoneAdder™panels are
wired.
When installing the CZ-4 panel it is important to pick a central location
where it is most convenient to bring all the wires. Most often this is at
the furnace or air handler. It is often the most convenient location
and closest to power, the HVAC unit controls and the zone dampers
when typically located at or near the plenum.
The CZ-4 case and cover are made of sturdy ABS plastic and can be
mounted to any flat surface. It is recommended that the panel be
mounted to a wall or return plenum and NOT on the furnace or
plenum where it will be in contact with the hot temperatures.The
panel can be located in an attic space or in an enclosed cabinet of a
rooftop unit, in order for the panel to be out of direct exposure to the
elements.
The cover easily removes from the case by pulling firmly and
separating the cover from the case exposing the circuit board. There
are 4 key-hole mounting points in each corner of the case. The case
has openings in the rear of the case as well as the side for all wiring.
Wiring can come from the back as well as the side in order to make a
neat installation.
OPERATION
The CZ-4 can control various types of HVAC Equipment all from the
same panel. The CZ-4 features allow the use of single stage
thermostats to control up to three stage heating and two stages
cooling and simple heat pump thermostats to control heat pumps.
The CZ-4 has various features that make installation and checkout
very simple for all of the board’s functionality.
The CZ-4’s basic function is zone control. On a call for heating or
cooling, the panel will accept the first call from any zone. Upon
accepting this call the CZ-4 will open the damper(s) to the zone(s)
calling, close the damper(s) to those zones not calling, activate the
needed HVAC controls for heating or cooling, whichever is being
called and not accept any calls for the opposite mode.
Zone Terminal Connections
for Zone Thermostats
& Zone Dampers
24VAC
Transformer
Terminals
Automatic
Resetting Fuse
Zone Calling
Indicators
Mode DIP
Switches
HVAC
Equipment
Connections
Leaving Air Sensor
(CLAS) Terminals
ZONE ADDER
(CAZ-2 panel)
RJ11 Connection
Adjustable
Heating Limit
Mounting
Keyholes
Two at Top
also.
Adjustable Second
Stage Timer
Power Indicator
LED
Boot Button
System Mode
Indicator LED
Purge Override
Button
No Sensor Jumper

FORM 2045-2 1306 ©2013 White-Rodgers by Permission 37-6864B
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Any calls for the opposite mode will be locked out until the initial
mode is either satisfied or a period of time has elapsed that is
sufficient for the first mode to satisfy, a maximum of 20 minutes, when
both calls occur simultaneously. An exclusive sequence determines
the time the unit has been running or needs to continue to run in
order to adequately provide conditioning for each mode. If a
particular mode has already been calling for 20 minutes or longer and
an opposite call comes in the CZ-4 will immediately drop the mode,
enter the purge mode in order to dissipate the conditioned air into the
zones calling before switching over to provide the new conditioning
call to its zones.
When using the CZ-4 to control multi-stage heating and/or cooling,
the extra stages are controlled based upon time after the first stage
call from the thermostat. When any zone calls the panel’s built-in
timer begins and after the set period of time elapses the CZ-4 will
also activate the W2 for Heating or Y2 for Cooling. In heating, after
the second stage is activated the same timer will control the third
stage of heating. The Stage Timer is adjustable from 5 to 23 minutes
after the first stage call. Once the extra stages are on, these stages
will continue to run until the first stage is satisfied or the Leaving Air
Sensor limit setting is reached. (See Leaving Air section for further
information.)
Once all zone thermostats are satisfied for heating and cooling, the
CZ-4 will accept Fan calls allowing Continuous Air Circulation(CAC)
in those zones where the thermostat’s Fan Switch is set to ON.
These zone dampers will be Open while the dampers to the zones
where the Fan Switch is set to AUTO will be CLOSED.
When all zone thermostats are satisfied for both Heating and Cooling,
and all Fan switches are set to AUTO position, the HVAC unit will be
off and all zone dampers will return to a normally open position.
Once a zone calls for heating, cooling or fan, the dampers to the
calling zones remain open and the dampers to the zones not calling
will close.
Set-Up for Various HVAC Equipment
The CZ-4 is factory set for conventional fossil fuel (oil or gas) single
and up to three stage heating and two stage cooling. The panel only
needs to be configured when using with a conventional electric
furnace or hydro-air system in order to bring the fan on with a call for
heat, or when using with heat pump equipment and thermostats.
Most all of the panel configuration is done by setting the DIP switches
in the lower center of the panel. Below is show their setting and
functions.
1. HP EQP – Heat Pump Equipment – This switch changes
the output of the HVAC Equipment terminals from
conventional Heating and Cooling to a traditional Heat
Pump Output. When OFF, a heat call activates the W1
output and the second stage activates W2. When ON a
Heat call activates the Y1 output to bring on the
compressor for first stage and Y2 for the second stage, of
both heating and cooling. W3 is activated on a third stage
call in either mode.
2. FAN HEAT – Activates the G output to turn the Fan on with
a call for Heat. This is used for Heat Pumps, Electric Heat
furnaces and Hydro-Air Systems. In the OFF position the
CZ-4 will not activate the Fan in heating unless there is a
fan call from one of the zone thermostats.
3. O TO W – Switch is placed to ON when using Heat Pump
thermostats that use an O terminal to activate the reversing
valve in COOLING. The O on the thermostat is wired to W
on the zone terminal in order to determine if the call is for
heating or cooling. All zone thermostats must operate and
be wired the same way.
4. B TO W – Switch is used when using Heat Pump
thermostats that use a B terminal to activate the reversing
valve in HEATING. The B terminal on the thermostat is
wired to W on the zone terminal in order to determine if the
call is for heating or cooling. All zone thermostats must
operate and be wired the same way. NOTE: Some OEMs
use the B terminal as a transformer Common and not
as the heating reversing valve. These thermostats will
use the O terminal for the reversing valve and should
be wired accordingly using DIP Switch #3. The B
terminal will then be wired to the C terminal on the
thermostat terminal block.
5. FAN PRG – This switch keeps the fan running during the
purge time in order to dissipate the conditioned air into the
last zone(s) calling. Placing this switch to ON, prevents the
fan from turning off from the fan control in the HVAC Unit
during the purge mode and coming back on moments later
if another call is waiting. In OFF the fan will be control by
HVAC Fan controls. This is desirable in residential to
prevent cold drafts after heating by having the switch OFF.
6. EMG HEAT – EMERGENCY HEAT – This switch can be
used to place all zones into the Emergency Heat mode.
This switch would be used when single stage thermostats
are used. NOTE: The System LED will flash RED when
this switch is on in the Heat Pump Mode ONLY.
7. ZONE STG – STAGE CONTROL – This switch is used to
control how the second stage of heating and cooling is
determined. In the OFF position, the second stage is
controlled by the timer. In the ON position the second
stage is brought based on the number of zones calling.
Greater than 50% of the zones calling will bring on the
second stage, for both heating and cooling.
8. CTRL 3 – Future Use
One of the many features of the DIP switches is if at any time the
equipment is changed from single stage to heat pump or vice versa
the thermostats do not need to be changed with the equipment
change. Changing the DIP switch settings is all that is needed.
Leaving Air Temperature Sensor (CLAS)
The Leaving Air Temperature Sensor, Model CLAS, is a remote
sensor that is located in the supply air duct to sense the leaving air
temperature of the HVAC Unit. The CLAS is a high limit protection for
the heating and a low limit protection for the cooling. When zoning,
the airflow through the HVAC Unit is critical. The CLAS protects the
equipment in low air flow situations as well as when by-pass air is
being directed back into the return air duct.
The heating limit is adjustable from 100°F to 170°F. The cooling limit
is fixed at 40°F. When the CLAS senses heating above its set point,
or cooling below its set point, the CZ-4 will drop both stages of
heating or cooling. The CLAS must sense a 10°F fall for heating or
rise for cooling before re-activating the first stages of heating or
cooling. If two stage heating or cooling is being used the second
stage timer will start again once the first stage is re-activated.
The CLAS requires 2 wires from the sensor to the LAT1 and LAT2
terminals on the CZ-4 panel.
LAT1
LAT2
NO SENSOR CLAS
NOTE: If the CLAS is not used, the NO SENSOR jumper located
near the LAT terminals must placed across the two pins.When
the sensor is used the jumper must be removed from the pins.
1 2 3 4
5 6 7 8
ON
OFF

FORM 2045-2 1306 ©2013 White-Rodgers by Permission 37-6864B
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Stage Timer
The CZ-4 has a built-in stage timer that eliminates the need and
added cost of using two stage thermostats. On a call for either
heating or cooling the timer begins. A minimum of 5 minutes,
adjustable to a maximum of 23 minutes, can be set in order to
activate the W2, W3 and Y2 outputs after the first stage call.
The Stage Timer is marked 0 through 9 and each increment is
indented as the dial is rotated. A minimum 5 minutes is set when the
dial is set to 0. To calculate the stage timing the dial setting is
multiplied by 2 and added to the base of 5 minutes. Example: Dial
setting is 3 x 2 = 6 + 5 = 11 Minutes for the Stage Timer.
When any zone calls the timer starts and activates the second stage
W2 or Y2 after the set time elapses. The timer also controls W3 after
the same time elapses after the W2 call.
PURGE TIME
The CZ-4 has a built-in Purge Time after each call is satisfied and
provides a minimum off time before another call is initiated. The
Purge Time is set at 2.5 minutes after all calls for a particular mode
are satisfied or when the Changeover Timer requires a changeover
due to opposing calls.
After all calls are satisfied or the changeover timer activates, the
Purge Timer begins and the heating or cooling, whichever was on, is
deactivated. Typically the fan may be running during this time and
the damper(s) to the last zone(s) calling will remain open to purge the
conditioned air only into those zones that were calling for the
conditioning. DIP Switch 5 can be set ON to keep the Fan running
during the Purge mode in order to prevent the fan cycling off and
back on between modes. In the instance where the Fan staying may
create a draft, and the frequency of opposite calls is minimal this
switch can be kept to OFF.
The CLR PRGE button on the top left of the panel can be pushed to
override the Purge mode and speed installation and checkout. This
button is only active when the System LED is AMBER.
Minimum On Timer
The CZ-4 also has a minimum on time whenever the compressor
operates in order to prevent frequent short cycling. Once there is a
call for cooling or the compressor on a heat pump, the CZ-4 will hold
that call for a period of 2 minutes.
CHANGEOVER TIMER
Whenever a call is made for either heating or cooling, the changeover
timer is activated in order to track the amount of time heating or
cooling is on. When an opposite call is made, after an opposite call
exists, the changeover timer calculates the amount of time the unit
has already been supplying the first mode in order to determine how
long it will hold off the opposite call. If an opposite call is made
shortly after the first call, the opposite call may be held off for as
much as 20 minutes. If the first call or subsequent calls for the first
call mode has had that mode operating for up to 20 minutes already
and an opposite call comes in after 20 minutes, the changeover timer
will immediately recognize the opposite call, shutting off the current
mode, enter the purge mode and automatically switch to the opposite
mode.
The longer a call has been running up to 20 minutes, the shorter the
wait time will be for an opposite call. If a call is over 20 minutes and
an opposite call is made the changeover will be immediate following
the purge time. This intelligent changeover timing makes the CZ-4
unique to any other zoning system.
Zone Adder Control (CAZ-2)
The CZ-4 Zone Panel can be added onto with the Model CZA. The
CZA is available as a 2 zone adder panel and expands any CZ-4
panel to a maximum of ten (10) zones. The CZA panel is connected
by a 6 conductor RJ11 telephone cable. This makes wiring between
the CZ-4 and CZA literally a snap.
CHECKOUT
The CZ-4 has unique features that simplify the checkout of the
system and has LED readouts that constantly indicate the system
operation. Once 24 Volt Power is applied to the panel the Green
Power LED will illuminate. This will stay illuminated constantly when
power is applied.
The System LED will provide several different indications based upon
color and if it is flashing.
Heat ON – RED
Heat Limit – RED Flashing
EMG Heat (HP Mode Only) – RED Flashing
Cool ON - GREEN
Cool Limit - GREEN Flashing
Fan ON - AMBER
Purge/Time Delay – AMBER Flashing
Each zone has its own small Green indicator LED next to each zone
relay. This light is lit when the specific zoning is calling for the mode
shown on the System LED.
WIRING
The CZ-4 is very simple to wire and requires only a minimum number
of connections. The CZ-4 terminal blocks are screw-less and all
wires can easily be pushed into their respective terminal by de-
pressing the button for each point and releasing once the wire is
seated. To remove the wire, just press its button again and remove
the wire.
WIRING DIAGRAM 1 – Single Stage Thermostat
C W R Y G
E
G
Y
R
W/O/B
C
CLOSE
OPEN
COM
ZONE
CONNECTIONS
THERMOSTAT DAMPER
Single Stage Thermostat
WIRING DIAGRAM 2 – Single Stage, Two Stage and
Three Stage Heating Equipment and up to Two Stage Cooling
W2
W1
Y1
Y2
O
G
E
B
R
First Stage Cooling Relay
24V. Transformer
Second Stage Cooling Relay
First Stage Heat Relay
Fan Relay
EQ U IPM EN T
HEATING COOLING EQUIPMENT
Second Stage Heat Relay
W3
Third Stage Heat Relay
STG Time
5 MIN + 2X
CLR

FORM 2045-2 1306 ©2013 White-Rodgers by Permission 37-6864B
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WIRING DIAGRAM 3– Heat Pump Thermostats
C O/B R Y G E
E
G
Y
R
W/O/B
C
CLOSE
OPEN
COM
ZONE
CONNECTIONS
THERMOSTAT DAMPER
Heat Pump Thermostat
WIRING DIAGRAM 4 – Typical Heat Pump Equipment
Compressor Relay
Reversing Valve
24V. Transformer
Second Stage Heat Relay
Emergency Heat Relay
Fan Relay
EQ U IPM EN T
AIR TO AIR HEAT PUMP CONNECTIONS
HEAT PUMP CONTROLS
W2
W1
Y1
Y2
O
G
E
B
R
W3
Compressor Relay
Reversing Valve
24V. Transformer
Second Stage Heat Relay
Emergency Heat Relay
Fan Relay
EQ U IPM EN T
AIR TO AIR HEAT PUMP CONNECTIONS
HEAT PUMP CONTROLS
W2
W1
Y1
Y2
O
G
E
B
R
W3
TROUBLESHOOTING
The CZ-4 is a very simple control to troubleshoot, especially with the
LED indicators. The only other device needed is a simple Volt/Ohm
meter. Almost all problems can be traded to an external component
or wiring to the CZ-4. While the CZ-4 has been designed to operate
under extreme voltage conditions and is fuse protected, like any
computer the micro-processor can hang up and not operate properly.
For these instances a BOOT button has been installed that re-boots
the micro-processor just like your computer. Pressing this button for
a few seconds and then release it will allow the micro-processor to re-
boot and in most all cases eliminate the problem. If not the following
procedure can help isolate the problem.
Zone(s) Not Calling
Each zone has a Green LED next to the zone relay when it is calling
and that calling is being recognized by the CZ-4. If a zone is
supposed to be calling and the Zone LED is not on, check for 24VAC
across the thermostat terminal C and the Y, if a Cool call, W if a Heat
Call, or G if a Fan call. If there is no voltage here at the panel the
panel is not getting the signal from the thermostat. The problem is
mis-wiring, a broken wire or a problem in the thermostat. To check
the zone on the panel, place jumper from R to Y, R to W or R to G to
see that the panel is operating properly.
Zone(s) Will Not Shut Off
If a zone will not stop calling, the Zone LED should still be on.
Depending on the call disconnect the Y, W or G wire from the
terminal strip. The zone will drop out. Check the thermostat wiring
for a mis-wiring or short that keeps the zone calling.
Damper Motor Checkout
Each zone has Green indicator light located to the right of the zone
damper’s relay. When all zones are satisfied all zone LEDs are lit
Green indicating all zone dampers will be Open. To check this there
will be 24VAC across the COM and Open terminal. When any zone
calls, the damper(s) to the satisfied zone(s) will power close and the
indicator light will go out. When the damper is to be closed there will
be 24VAC across COM and CLOSE.
St. Louis, MO. Markham, Ontario
www.white-rodgers.com
BOOT

FORM 2045-2 1306 ©2013 White-Rodgers by Permission 37-6864B
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CZ-4 WIRING DIAGRAM
C W R Y G
E
G
Y
R
W/O/B
C
CLOSE
OPEN
COM
ZONE
CONNECTIONS
THERMOSTAT DAMPER
Single Stage Thermostat
C W R Y G
E
G
Y
R
W/O/B
C
CLOSE
OPEN
COM
ZONE
CONNECTIONS
THERMOSTAT DAMPER
Single Stage Thermostat
C W R Y G
E
G
Y
R
W/O/B
C
CLOSE
OPEN
COM
ZONE
CONNECTIONS
THERMOSTAT DAMPER
Single Stage Thermostat
C W R Y G
E
G
Y
R
W/O/B
C
CLOSE
OPEN
COM
ZONE
CONNECTIONS
THERMOSTAT DAMPER
Single Stage Thermostat
ON
OFF
HEAT PUMP EQUIP
FAN ON IN HEAT
STAT O TO W
STAT B TO W
FAN IN PURGE
EMERGENCY HEAT
STAGE TIME/ZONE
CTRL 3
1 2 3 4 5 6 7 8
W2
W1
Y1
Y2
O
G
E
B
R
First Stage Cooling Relay
24V. Transformer
Second Stage Cooling Relay
First Stage Heat Relay
Fan Relay
EQ U I PM EN T
HEATING COOLING EQUIPMENT
Second Stage Heat Relay
W3
Third Stage Heat Relay
C
R
24VAC
24VAC
LAT1
LAT2
NO SENSOR CLAS
100F
135F
170F
100F
135F
170F
0
1
2
34567
8
9
0
1
2
34567
8
9
BOOT
CLR PURGE
STG TIMER
5MIN +2x
HTG LIMIT
POWER
SYSTEM