Zonex System 2000 GEN II User guide

System 2000
GEN II
A MODULATING SYSTEM
Vote Based Auto Changeover VAV
Part #GENIIMAN
June 2014
Installation and Applications Manual

GEN II
QUICK START AND COMMISSIONING
Follow these Quick steps for a successful job
If you need additional information, please read the GEN II Manual
1. Install GEN II Controller in an easily accessible location for your customer.
2. Install an Independent 24 Volt 40 VA transformer, and connect to the TR1 and TR2 terminals
on the GEN IIcontroller.
3. Install the LAT sensor in the supply air, ahead of any bypass takeoffs. Wire sensor to the S S
terminals on the GEN II controller.
4. Install Dampers and Bypass Dampers.
5. Install all thermostat sub-bases.
6. Wire R & C Terminals from the GEN II Controller to the first sub-base – only (18 ga.
Thermostat wire).
7. Wire RX & TX Terminals from the GEN II Controller using Belden 8740 twisted pair wire to
the first thermostat sub-base – only.
8. Damper wiring – connect RO, RC, MC wires from each thermostat to its damper with 18 GA
thermostat wire.
9. Plug 1 MODSTAT into that sub-base.
10. Address that thermostat to #1 – see Pages 10-13 for MODSTAT installation, addressing and
operation.
11. Turn on GEN II Controller switch “E”. Power light should light up and then look at the Display
"O" on the GEN II Controller, and the number 01 appears on the Display. This indicates you
are communicating with the first thermostat.
12. If you don’t see the #1 and a 0 is displayed, check the address. If the address is #01, then
check wires for R&C polarity and RX TX for correct connections.
13. If #1 is displayed on the GEN II Controller, then daisy chain wires from Stat 01 to the next stat
and address it #2; then repeat the ON – Off switch operation and confirm the #2 shows up on
the display indicating the system is now communicating with 2 thermostats.
14. Continue adding MODSTATS, and confirm communication by repeating the ON – Off switch
operation until all stats are wired and the total number of thermostats on your job shows up
on the display on the GEN II Controller. (If you are adding stand-alone units to the GEN II
Controller, see #15. If not, skip to #16)
15. If there are any stand-alone units that are going to be managed by the GEN II Controller,
install DIGICOM / DIGIHP stats at this time. Continue the RX & TX daisy chain from the last
MODSTAT to the DIGICOM / DIGIHP and wire in the stand-alone unit at this time and
address the DIGICOM / DIGIHP (see Pages 14-17 for installation, addressing and
operation). Confirm communication by repeating the On – Off switch operation until all stats
are wired and the total number of thermostats on your job shows up on the display on the
GEN II Controller.
16. Go to any MODSTAT and make a Cool Call. Look at the GEN II Controller and confirm Y1
(yellow LED) and G (green LED) lights are on.
17. Turn off the Cool Call to be sure Y1 and G turn off at GEN II Controller.
18. Repeat with Heat Call for W1 (red LED).
19. Wire GEN II Controller to A/C unit.
20. Set stat to call for cool, and check register to be sure each damper opens and closes as you
make and satisfy calls.
For Advanced Feature Configuration or additional operating information, review the attached
GEN II Manual.

GEN II
QUICK START AND COMMISSIONING
The GEN II is equipped with a Digital Display (O) on the GEN II controller that constantly
displays Leaving Air Temperature from the unit. At startup, this display also reports the number
of thermostats communicating with the GEN II controller. The display and 3 buttons (N) beneath the
display provide the installing contractor the ability to tailor the system to your specific application.
The GEN II controller is shipped from the factory configured for basic Gas/Electric operation.
However, the following should be checked as part of the initial installation setup procedures:
1. EH jumper (A) is installed by the factory on one pin for normal gas heat operation where the fan
is controlled by the HVAC system fan control. When a fan output is required from the GEN II
controller on a call for heat, place the EH jumper over both pins for several seconds and then
remove. Place the jumper tab on one pin.
2. O/B and HP jumpers (B&C) should both be on one pin or removed for GE operation.
3. PRIORITY jumper (D) should be on one pin.
Note: If the Priority opposing zone strategy is to be used, this jumper position will be changed
after the initial system start-up is completed.
See Advanced Feature Configuration.
4. Set the power switch (E) to ON.
5. Set the NIGHT DAY switch (L) to the DAY position.
6. Set the fan jumper (M) to AUTO for intermittent operation or ON for constant ON operation in
the Occupied mode.
7. Place the LOCK – UNLOCK switch (P) in the UNLOCK position.
8. Place the TIME/TEMP jumper (Q) on the middle and upper pins to control Y2 and W2 staging
on run time and supply air temperature.

Table of Contents
Page
System Overview
....................................................................................................................................1
System Overview Diagram ..................................................................................................................1
General Sequence
of Operation............................................................................................................2
Gas Electric Operation
...........................................................................................................................3
Controller ID Diagram ..........................................................................................................................3
Installation Controller ...........................................................................................................................3
GE Controller Configuration .................................................................................................................
4
GE Advanced Configuration ................................................................................................................5
H&C Cut-out Temperature ...................................................................................................................
5
Electric Heat Fan .................................................................................................................................5
2nd Stage cut in ....................................................................................................................................5
Heat Pump Operation
.............................................................................................................................6
Controller ID Diagram ..........................................................................................................................6
Heat Pump Installation .........................................................................................................................
7
Basic Configuration ..............................................................................................................................
8
Heat Pump Advanced Configuration ...................................................................................................8
H&C Cut-out Temperature ...................................................................................................................
8
2nd Stage Cut-in ...................................................................................................................................9
Zone Therm
ostat – ModStat
ModStat Installation ...........................................................................................................................10
Wiring Diagram ..................................................................................................................................10
ModStat Configuration ..................................................................................................................11-
12
Supplemental Heat Applications ...................................................................................................
.....13
Zone Thermostats
– DIGICOM / DIGIHP
DIGICOM / DIGIHP Installation ....................................................................................................14-15
DIGICOM / DIGIHP Configuration ................................................................................................16-17
Voltage Polarity .................................................................................................................................17
System Start and Test .........................................................................................................................18
Troubleshooting ...................................................................................................................................18
Advanced Feature Configuration
Gas Electric and Heat Pump .............................................................................................................19
Occupied/Unoccupied Fan ................................................................................................................19
Opposing Call Changeover ...............................................................................................................19
Priority Demand ................................................................................................................................19
Thermostat Security – LOCK ............................................................................................................20
Air Balance ........................................................................................................................................20
Default Thermostat Set Points ..........................................................................................................21
Time Clock (GCLK) ...........................................................................................................................21
Zone Dampers
Round Dampers ................................................................................................................................22
Rectangular Dampers .......................................................................................................................23
D-Fuser .............................................................................................................................................24
Sizing ................................................................................................................................................25
Slaving Zone Dampers .....................................................................................................................25
Bypass Dampers
– Electronic
Bypass Dampers ...............................................................................................................................26
Slaving Bypass Dampers ..................................................................................................................27
Bypass Damper with Integrated Pressure Control........................................................................28-29

1
SYSTEM OVERVIEW
The SYSTEM 2000 GEN II is a commercial modulating or 2-position zone control system controlling
2-17 independent zones per unit. The GEN II controller is designed for Auto Change- over, multi-
stage Heat Pump (2C/3H) and Gas Electric (2C/2H) applications.
For modulating applications, the GEN II system uses the Zonex ModStat, which controls the “ST”
series, 3-wire, 24-volt, power open / power close round and rectangular dampers. For 2-position
damper applications, the GEN II system uses the Zonex MODS2 thermostat. The MODS2
thermostats control the TR round or TREC rectangular series, 2-wire, power close / spring open,
low pressure dampers. The TR / TREC series dampers are designed for systems 5 tons or less
(2000 CFM).
Sophisticated, integrated software allows for a wide range of system control and changeover
strategies, allowing the contractor to tailor the GEN II system to your specific application.
Additional features include LED status indication of all system functions, digital LAT display, fully
adjustable capacity control with on-board limit settings, and optional staging strategies. Night
setback operation is standard, with selectable 2-hour override at each stat, along with a unique
feature to remotely lock thermostats in the system.
The system provides the installing contractor with a simple startup diagnostic to minimize wiring
errors and speed installation.
GEN II is recognized as the Industry's easiest zone control system to install and wire. The GEN II
System operates over an unshielded two-wire data link, along with two 24 V power wires all daisy
chained from stat to stat with no home run wiring required. Three wires from the stat to actuator
control a modulating damper in each zone.
The GEN II system does not require a computer to set up or operate.

2
System 2000 GEN II offers the following additional control features:
1. Set Cooling and Heating capacity cut-out set points
2. Adjustable timing to initiate 2nd stage operation
3. Adjustable opposing call changeover timing
4. Priority demand votes on a stat-by-stat basis
5. Provide default occupied and unoccupied set points on every stat
6. Open all dampers for air balancing
System 2000 GEN II components:
• GEN II controller (includes integrated capacity control)
• Zone thermostats
• Power open / power close 24vac supply dampers
• Power open / power close 24vac bypass damper with static pressure control
• Communication cable (Belden 8740) twisted pair
• Time Clock (optional)
• 24vac 40va transformers: 1 to control system and dampers
1 for bypass damper and static pressure control
• Stand-alone thermostat – non-zoned system
GENERAL SEQUENCE OF OPERATION
When the GEN II controllers are powered up, the total number of addressed thermostats (ModStat,
MODS2, DIGICOM, DIGIHP) are determined and verified on the display. This confirms the
controller is communicating with all thermostats in the system. If there are no active heat or cool
calls detected, the supply dampers will modulate to 50% open (ModStat) or full open (MODS2) for
ventilation mode. Additional thermostats may be utilized to control stand-alone rooftop units with
DIGICOM / DIGIHP thermostats. The system blower operation can be configured for constant ON
or intermittent Auto. The controllers are shipped from the factory for Auto fan.
The System 2000 GEN II systems can be field configured for adjustable time based opposite call
changeover, vote based majority changeover, or priority vote changeover by thermostat
assignment. The GEN II controllers are shipped from the factory for 10-minute opposing call
changeover. The GEN II controllers “poll” the thermostats once per minute to determine the
thermostat demand status for heat and cool. The heat and cool changeover functions will operate
by the type of changeover selected on the controller. When the GEN II controllers change modes,
a 5-minute purge cycle is initiated before the changeover is completed.
On active heat or cool calls, the non-calling zones will modulate to the close position, or close 100%
depending on the thermostat being used. When the last calling zone is satisfied in either heat or
cool mode, the GEN II controllers will terminate the HVAC outputs after the next “poll”; and the
blower output will be de-energized (unless controller is configured for constant fan) for a 5-minute
purge cycle. During the purge cycle no heat or cool calls are recognized.
When the system is in the heating mode and calls for cooling are received, an opposing call timer
strategy operates. This timer is adjustable from 5–30 minutes. The factory default is 10 minutes.
At the end of the selected time period, if the opposing call is 3 degrees away from set point, heating
is turned off. After a 5-minute purge cycle, Cooling is turned on until the cool call is satisfied. If
necessary, GEN II will return to the heating mode. If all calls have been satisfied, dampers will
modulate to the 50% open position for ventilation. If the opposing zone strategy is not desired, this
feature may be disabled.
This mode may be enhanced by adding Priority votes to each thermostat in the system, thereby
weighting certain zones more than others. This Priority mode allows you to select 0, 1, or 2
additional votes for a thermostat that has unusual loads, like a conference room.

3
GAS ELECTRIC OPERATION
General Installation Instructions
GEN II Controller
1. Install the GEN II controller on an interior wall where the ambient temperature is between 32°-
120°F (0°- 48°C) non-condensing. This controller is to be installed in an accessible interior
area; not in attics or above ceilings.
2. The controller is to be powered by a dedicated 24vac 40va transformer.
The transformer secondary is wired to TR1 TR2 on the controller (G).
The secondary voltage to the controller must be 24 to 28vac.
LEGEND
A EH Jumper (Set Up Fan Operation for
Electric Heat)
B O/B Jumper (Heat Pump Only –
Reversing Valve Operation)
CH/P Jumper (Jump for Heat Pump
Operation)
D Priority Jumper (Allows for Priority Vote
Setup)
E On / Off Switch
F R C Power to ModStats (18 ga.
Thermostat wire)
G 24-Volt Transformer
H TC – TC Time Clock Terminals
I Unit Terminals
J S S Terminals – Leaving Air Sensor
(LAT)
K RX – TX Communications Wire
L Day / Night Switch
M Fan Jumper (Continuous or Auto)
N Up / Down / Set Buttons (High Limit,
Low Limit, Set)
O Digital Display (Leaving Air Temperature
and configuration)
P Lock / Unlock (Lock Thermostats)
Q Staging Strategy (Time / Temperature or
Time Only)
TERMINAL FUNCTIONS / CONNECTIONS
TX / RX – Data Transmit / Receive
S S – Leaving / Supply Air Sensor Input
G – Fan Output
W2 – Auxiliary / Emergency Heat
O/B – Reversing Valve Output
Y2 – Stage 2 Cool Output
Y1 – Stage 1 Cool Output
R – 24vac from Unit Transformer
TC / TC – Time Clock Input for Occupied /
Unoccupied Operation
TR1 / TR2 – 24vac Power Input / Common
R / C – Stat Power Daisy Chain Stat to Stat
(18 ga. Thermostat wire)

4
3. Install the leaving air sensor (LAT) in the supply air, ahead of the bypass take-off. Sensor wires
are connected to the S S terminals on the controller (J). The LAT sensor leads may be
extended using standard 18/2 thermostat wire.
4. The leaving air sensor (LAT) is calibrated to the controller at the factory. However, the
calibration should be checked as part of the system setup procedures. If adjustments are
required, use the Blue potentiometer labeled R44 located in the upper left hand corner of the
GEN II controller. Screw the pot clockwise to lower the display temperature and counter -
clockwise to raise the temperature. NOTE: The display will update every 10 seconds.
5. Confirm you have connected the RX TX communication wires and Rand C from the
thermostats to the controller (F&K), F = (R C), K = (TX RX). (Communication wire maximum is
4,000 ft. from the Command Center to the farthest ModStat, DIGICOM or DIGIHP.)
6. Connect the output wires from the controller to the HVAC system using standard 18 ga.
thermostat wire.
The LAT sensor leads may be extended using standard 18/2 thermostat wire.
Gas Electric - Basic GEN II Controller Configuration
The GEN II is equipped with a Digital Display (O) on the GEN II controller that constantly
displays Leaving Air Temperature from the unit. The display and 3 buttons beneath the display
provide the installing contractor the ability to tailor the system to your specific application.
The GEN II controller is shipped from the factory configured for basic Gas/Electric operation.
However, the following should be checked as part of the initial installation setup procedures:
1. EH jumper (A) is installed by the factory on one pin for normal gas heat operation where the fan
is controlled by the HVAC system fan control. When a fan output is required from the GEN II
controller on a call for heat, place the EH jumper over both pins for several seconds and then
remove. Place the jumper tab on one pin.

5
2. O/B and HP jumpers (B&C) should both be on one pin or removed, for GE operation.
3. PRIORITY jumper (D) should be on one pin.
Note: If the Priority opposing zone strategy is to be used, this jumper position will be changed
after the initial system start-up is completed.
See Advanced Feature Configuration.
4. Set the power switch (E) to ON.
5. Set the NIGHT DAY switch (L) to the DAY position.
6. Set the fan jumper (M) to AUTO for intermittent operation or ON for constant ON operation in
the Occupied mode.
7. Place the LOCK – UNLOCK switch (P) in the UNLOCK position.
8. Place the TIME/TEMP jumper (Q) on the middle and upper pins to control Y2 and W2 staging
on run time and supply air temperature.
GEN II Gas Electric Advanced Feature Configuration
Gas Electric Capacity Control -Cool and Heat cut-out temperature adjust
The factory setting for the Cool and Heat cut-out temperatures is 45°- 145°F (7°- 62°C). This can
be easily changed with the following procedure:
1. Cool cut-out temp – Press the DN button (N);“C” will be displayed and then the cut-out
temperature.
2. LOWER – Press the DN button; after the “C” is displayed, continue to hold the DN button until
the desired temperature is displayed; then release.
NOTE: The controller will not change the Cool cut-out lower than 40°F (4°C).
3. RAISE – Press the DN button; after “C” is displayed, immediately release the DN button and
press the UP button. Hold until the desired temperature reading is displayed, and release.
4. Press the DN button to verify the new cool cut-out temperature.
Heat cut-out temperature - Press and hold the UP button; after the “H” is displayed, use the same
procedure as above to raise or lower the displayed temperature.
Electric Heat - Fan Configuration
EH jumper (A) is installed by the factory on one pin for normal gas heat operation where the fan is
controlled by the HVAC system fan control. When a fan output is required from the GEN II
controller on a call for heat, place the EH jumper over both pins for several seconds and then
remove. Place the jumper tab on one pin.
2nd Stage Heat and Cool Cut-in Configuration
The GEN II controller is set up at the factory to stage Y2 and W2 cut-in operation based on a 3-
minute time delay and supply air temperature. This is done with a jumper which is placed on the
middle and upper pins on TIME/TEMP (Q), and the cut-in delay set at 03 (3 min) in the controller
program. The cut-in temperatures are fixed in the controller program at 57°F (13°C) and higher for
Y2 and 120°F (48°C) and lower for W2. The Y2 and W2 cut-in delay sequence can be field
adjusted (see below).
Adjust 2nd Stage Cut-in Time Delay
1. To increase the Y2 and W2 cut-in delay, press and hold the SET and DN buttons (N)
simultaneously. When 03 appears in the display, release the buttons and immediately press
the UP button and hold until the desired delay time is displayed, and release. The time delay
is fully adjustable from 3 - 20 minutes. To verify the change, press and hold the SET and DN
buttons simultaneously until the delay time is shown, and release.

6
2. To decrease the Y2 and W2 cut-in delay, press and hold the SET and DN buttons (N)
simultaneously. When delay time appears in the display, release the buttons and immediately
press the DN button and hold until the desired delay time is displayed, and release. To verify
the change, press and hold the SET and DN buttons until the delay time is shown, and release.
Configure 2nd Stage Cut-in For Time Delay and Thermostat Demand Only
1. Place the 2nd stage configuration jumper (Q) on the middle and lower pins - TIME.
2. If the cut-in time delay must be changed from the factory setting of 03 (3 min), follow the above
procedures to raise or lower the time delay value.
3. Verify time delay value by pressing the SET and DN buttons simultaneously.
HEAT PUMP OPERATION
TERMINAL FUNCTIONS / CONNECTIONS
TX / RX – Data Transmit / Receive
S S – Leaving / Supply Air Sensor Input
G – Fan Output
W2 – Auxiliary / Emergency Heat
O/B – Reversing Valve Output
Y2 – Stage 2 Cool Output
Y1 – Stage 1 Cool Output
R – 24vac from Unit Transformer
TC / TC – Time Clock Input for Occupied /
Unoccupied Operation
TR1 / TR2 – 24vac Power Input / Common
R / C – Stat Power Daisy Chain Stat to Stat
(18 ga. Thermostat wire)
LEGEND
A EH Jumper (Set Up Fan Operation for
Electric Heat)
B O/B Jumper (Heat Pump Only –
Reversing Valve Operation)
CH/P Jumper (Jump for Heat Pump
Operation)
D Priority Jumper (Allows for Priority Vote
Setup)
E On / Off Switch
F R C Power to ModStats (18 ga.
Thermostat wire)
G 24-Volt Transformer
H TC – TC Time Clock Terminals
I Unit Terminals
J S S Terminals – Leaving Air Sensor
(LAT)
K RX – TX Communications Wire
L Day / Night Switch
M Fan Jumper (Continuous or Auto)
N Up / Down / Set Buttons (High Limit,
Low Limit, Set)
O Digital Display (Leaving Air Temperature
and configuration)
P Lock / Unlock (Lock Thermostats)
Q Staging Strategy (Time / Temperature or
Time Only)