CALEFFI Z-one ZVR10 Series User manual

Function
The ZVR series is a multi-zone zone valve and boiler
operating control for multiple zone hydronic heating or
cooling systems. The ZVR series interfaces with low
voltage thermostats, or any other low voltage controllers
having a switching action. The ZVR series controls up
to 3, 4, 5 or 6 zones, depending on model selected.
In addition, a system circulator pump and secondary
pump is turned on whenever any zone calls for heat.
LED indicators provide functional status and easy
system troubleshooting. The ZVR series is a perfect
match with Caleffi’s Z-one™ motorized zone valves.
• Compatible with low voltage 2, 3, or 4 wire thermostats
• R, W, C and TT Comm dual labeling at thermostat terminals
• Z-oneLink unlimited zone expansion
• Selectable priority with 1 hour time-out feature
• System pump status selectable during priority
• Circulator will start only after the zone valve end switch is closed
• Dry contacts for DHW (ZR/ZC), capable of switching line voltage
• Large terminal connections
• High Capacity 40 VA Transformer standard for 3 and 4 zone models-expandable to 80 VA,
and 80 VA for the 6 zone model
• Automatic resettable fuse
• Controls system pump, secondary pump, and priority pump
• Front LED Lights
• 100% Factory tested with 3 year warranty
• ETL Approved
Technical specifications
Materials
Housing plastic: ABS
Front display lights: LCD
Electrical Knockouts: (12) 1/2" size
Performance
Power supply: 120 VAC, 50/60 Hz
Transformer voltage: 24 VAC
Maximum transformer load: 40 VA (ZVR103/4), 80 VA (ZVR106)
Electrical switch rating: 20A Max Combined
Electrical switch rating, ZR/ZC, DHW, XX: 120 VAC, 2A each
Electrical switch rating pumps: 120 VAC, 5A each
Resettable Fuse: automatic
Maximum temperature: 110°F (43°C)
Maximum humidity: 90% non-condensing
Approvals: Certified to CSA C22-2 No.24
Conforms to UL Standard 873
NA10333
Z-one™ Relay Multi-Zone Valve Control
ZVR10X series
www.caleffi.com
© Copyright 2014 Caleffi
Product Range
Code ZVR103 Z-one™Relay switching relays...............................................................three zone
Code ZVR104 Z-one™Relay switching relays.................................................................four zone
Code ZVR106 Z-one™Relay switching relays...................................................................six zone

SAFETY INSTRUCTION
This safety alert symbol will be used in this manual to draw attention to safety
related instructions. When used, the safety alert symbol means ATTENTION!
BECOME ALERT! YOUR SAFETY IS INVOLVED! FAILURE TO FOLLOW
THESE INSTRUCTIONS MAY RESULT IN A SAFETY HAZARD.
CAUTION: All work must be performed by qualified personnel trained in the
proper application, installation, and maintenance of systems in accordance
with all applicable codes and ordinances.
CAUTION: Electrical shock hazard. Disconnect power before installation to
prevent electrical shock or equipment damage. Make sure all connections
are in accordance with the electrical wiring diagram and in accordance with
national and local electrical codes.
WARNING: Avoid electrical noise interference. Do not install near large
conductors, electrical machinery, or welding equipment. Avoid locations
where excessive moisture, corrosive fumes, vibration, or explosive vapors are
present.
Caleffi shall not be liable for damages resulting from misapplication or misuse of it products.
Dimensions
POWER
ZONE 1
ZONE 2
ZONE 3
ZONE 4
ZONE 5
ZONE 6
ZVR106
Six zone switching - Input: 120VAC 50/60Hz 20A MAX
Conforms
to UL 873
4009064
CAUTION: RISKOF ELECTRIC SHOCK - DISCONNECT ALL
INPUTPOWER PRIOR TO SERVICING
Milwaukee,WI 53208 USA
POWER
ZONE 1
ZONE 2
ZONE 3
ZONE 4
ZONE 5
ZONE 6
T-STAT
CALL
VALVE
OPEN
Code Zones A B C Wgt. (lbs)
ZVR103 3 9 1/4"11"3"3.2
ZVR104 4 9 1/4"11"3"3.2
ZVR106 6 9 1/4"11"3"3.2
A
B C
C

Inspection
Inspect packages for damage. If damaged, notify the appropriate carrier
immediately. If undamaged, open the package and inspect the device for
obvious damage. Return damaged products.
• Use only copper conductor supply wire suitable for at least 105°C
• All circuits must have a common disconnect and be connected to the
same pole of the disconnect
Maintenance and Repair
The Caleffi Z-one™multi-zone valve control comes with a resettable
fuse and requires no maintenance. If control fails or is damaged, replace
control with functional one.
Mounting
Mount the Caleffi Z-one™switching relay box to a suitable surface.
Slotted holes are provided for mounting purposes. Do not mount to a
surface that exceeds 115°F (45°C). The unit must be only located in dry
interior locations. It is not suitable for installation in hazardous locations
and should not be placed close to any electromagnetic fields.
Installation
Cover removal
Hold either the left or the right
end of the box up and at an
angle. Use body for stabilizing
relay box.
Insert screwdriver and push tab
inward, cover should release from
base.
Roll cover off base.

Transformer
Installation
Mount box on stable surface
using level.
Remove transformer(s) from
packaging.
Slide bottom end of transformer
into bottom latch.
Snap top of transformer into latch
arms.
Feed wiring through hole near the
top of the transformer and insert
transformer plug into the socket.
Repeat process for 2nd
transformer if six valve relay box.

6 Zone
T-STAT 2
C
RW
T T COM
COMMS
DP
DHW
ZR/ZC
X X
T-STAT 3
C
RW
T T COM
T-STAT 1
C
RW
T T COM
L
PUMP 2
N
PRIMARY
PUMP
L
PRIORITY
PUMP 1
N
L
POWER IN
N
GROUNDS
L
PUMP 3
N
TRANSFORMER
LN
T-STAT 4
C
RW
T T C
OM
L
PUMP 4
NL
PUMP 5
NL
PUMP 6
N
T-STAT 5
C
RW
T T COM
T-STAT 6
C
RW
T T COM PWR
ZONE1
ZONE2
ZONE3
ZONE4
ZONE5
ZONE6
DipSwitches
Master Slave
Priority OFF Priority ON
Primary OFF Primary ON
Exercise OFF Exercise ON
Post Purge OFF Post Purge ON
ZSR106
When a zone has a demand from a thermostat (T T or R W) the control will send 24 VAC to the
corresponding zone valve. When the zone valve end switch closes, the primary pump will switch
on and the (X X) dry contacts will close to signal the boiler of a heating demand. Zone 1 can be
used for priority (either a priority pump or valve). When the priority jumper is ON, a demand from
T-Stat1 will activate 24VAC to valve 1 and the priority pump will switch on after the end switch
closes (requires a jumper in the end switch terminals if a valve is not used). The DHW (ZR/ZC)
dry contact will also close. Depending upon "Status During Priority" jumper, the system pump will
either be ON or OFF.
The jumpers on the ZVR series can be positioned for the
following operations.
Priority ON / Priority OFF: When priority jumper is ON, upon
demand, zone 1 will operate as priority and all other zones are
temporarily switched off (with 1 hour time-out). When priority
mode is OFF, any zones that were active when zone 1 was
switched on will remain on.
Status During Priority ON / Status During Priority OFF: When
status jumper is ON, the system pump will continue to operate
during priority.
Master / Slave: allows for unlimited expansion to additional ZVR
relays.
6 Zone
ZVR106
L
POWER IN
N
PWR
TSAT1 ZONE1
TSAT2 ZONE2
TSAT3 ZONE3
TSAT4 ZONE4
TSAT5 ZONE5
TSAT6 ZONE6
L
PRIORITY
PUMP
NL
SEC PUMP
N
STATUS
DURING
PRIORITY
ZONE 1
END
SWITCH
MOTOR
PRIORITY
ZONE 2
END
SWITCH
MOTOR
ZONE 3
END
SWITCH
MOTOR
ZONE 4
END
SWITCH
MOTOR
ZONE 5
END
SWITCH
MOTOR
ZONE 6
END
SWITCH
MOTOR
ON OFF
ON OFF
L
SYSTEM
PUMP
N
MASTER SLAVE
T-STAT 2
C
RW
T T COM COMMS
DP
DHW
ZR/ZC
X X
T-STAT 3
C
RW
T T COM
T-STAT 1
C
RW
T T COM
T-STAT 4
C
RW
T T COM
T-STAT 5
C
RW
T T COM
T-STAT 6
C
RW
T T COM
Large screw terminals connections makes wiring easy with three pump screw terminal connections.
Pump terminals connection have 120 VAC outputs for simplified pump connections. Zone valve
connections can be 2, 3 or 4 wire.
Z-oneLink unlimited expansion allows adding addition ZVR
series relay controls to a Master ZVR. Communication is
accomplished by connecting three wires (bell or thermostat
wire) to the communication terminals located in the upper
right hand corner. The jumper is positioned to Master / Slave
position. A demand for heat from any zone will fire the boiler
and start the pump.
6 Zone
ZVR106
L
POWER IN
N
PWR
TSAT1 ZONE1
TSAT2 ZONE2
TSAT3 ZONE3
TSAT4 ZONE4
TSAT5 ZONE5
TSAT6 ZONE6
L
PRIORITY
PUMP
NL
SEC PUMP
N
STATUS
DURING
PRIORITY
ZONE 1
END
SWITCH
MOTOR
PRIORITY
ZONE 2
END
SWITCH
MOTOR
ZONE 3
END
SWITCH
MOTOR
ZONE 4
END
SWITCH
MOTOR
ZONE 5
END
SWITCH
MOTOR
ZONE 6
END
SWITCH
MOTOR
ON OFF
ON OFF
L
SYSTEM
PUMP
N
MASTER SLAVE
T-STAT 2
C
RW
T T COM COMMS
DP
DHW
ZR/ZC
X X
T-STAT 3
C
RW
T T COM
T-STAT 1
C
RW
T T COM
T-STAT 4
C
RW
T T COM
T-STAT 5
C
RW
T T COM
T-STAT 6
C
RW
T T COM
6 Zone
ZVR106
L
POWER IN
N
PWR
TSAT1 ZONE1
TSAT2 ZONE2
TSAT3 ZONE3
TSAT4 ZONE4
TSAT5 ZONE5
TSAT6 ZONE6
L
PRIORITY
PUMP
NL
SEC PUMP
N
STATUS
DURING
PRIORITY
ZONE 1
END
SWITCH
MOTOR
PRIORITY
ZONE 2
END
SWITCH
MOTOR
ZONE 3
END
SWITCH
MOTOR
ZONE 4
END
SWITCH
MOTOR
ZONE 5
END
SWITCH
MOTOR
ZONE 6
END
SWITCH
MOTOR
ON OFF
ON OFF
L
SYSTEM
PUMP
N
MASTER SLAVE
T-STAT 2
C
RW
T T COM COMMS
DP
DHW
ZR/ZC
X X
T-STAT 3
C
RW
T T COM
T-STAT 1
C
RW
T T COM
T-STAT 4
C
RW
T T COM
T-STAT 5
C
RW
T T COM
T-STAT 6
C
RW
T T COM
6 Zone
ZVR106
L
POWER IN
N
PWR
TSAT1 ZONE1
TSAT2 ZONE2
TSAT3 ZONE3
TSAT4 ZONE4
TSAT5 ZONE5
TSAT6 ZONE6
L
PRIORITY
PUMP
NL
SEC PUMP
N
STATUS
DURING
PRIORITY
ZONE 1
END
SWITCH
MOTOR
PRIORITY
ZONE 2
END
SWITCH
MOTOR
ZONE 3
END
SWITCH
MOTOR
ZONE 4
END
SWITCH
MOTOR
ZONE 5
END
SWITCH
MOTOR
ZONE 6
END
SWITCH
MOTOR
ON OFF
ON OFF
L
SYSTEM
PUMP
N
MASTER SLAVE
T-STAT 2
C
RW
T T COM
COMMS
DP
DHW
ZR/ZC
X X
T-STAT 3
C
RW
T T COM
T-STAT 1
C
RW
T T COM
T-STAT 4
C
RW
T T COM
T-STAT 5
C
RW
T T COM
T-STAT 6
C
RW
T T COM
6 Zone
T-STAT 2
C
RW
T T COM
COMMS
DP
DHW
ZR/ZC
X X
T-STAT 3
C
RW
T T COM
T-STAT 1
C
RW
T T COM
L
PUMP 2
N
PRIMARY
PUMP
L
PRIORITY
PUMP 1
N
L
POWER IN
N
GROUNDS
L
PUMP 3
N
TRANSFORMER
LN
T-STAT 4
C
RW
T T COM
L
PUMP 4
NL
PUMP 5
NL
PUMP 6
N
T-STAT 5
C
RW
T T COM
T-STAT 6
C
RW
T T COM PWR
ZONE1
ZONE2
ZONE3
ZONE4
ZONE5
ZONE6
DipSwitches
Master Slave
Priority OFF Priority ON
Primary OFF Primary ON
Exercise OFF Exercise ON
Post Purge OFF Post Purge ON
ZSR106
Jumper set up
Wiring terminals

Example Wiring Diagram
6 Zone
ZVR106
T-STAT 2
C
RW
T T COM COMMS
DP
DHW
ZR/ZC
X X
T-STAT 3
C
RW
T T COM
T-STAT 1
C
RW
T T COM
L
POWER IN
N
T-STAT 4
C
RW
T T COM
T-STAT 5
C
RW
T T COM
T-STAT 6
C
RW
T T COM PWR
TSAT1 ZONE1
TSAT2 ZONE2
TSAT3 ZONE3
TSAT4 ZONE4
TSAT5 ZONE5
TSAT6 ZONE6
L
PRIORITY
PUMP
NL
SEC PUMP
N
STATUS
DURING
PRIORITY
ZONE 1
END
SWITCH
MOTOR
PRIORITY
ZONE 2
END
SWITCH
MOTOR
ZONE 3
END
SWITCH
MOTOR
ZONE 4
END
SWITCH
MOTOR
ZONE 5
END
SWITCH
MOTOR
ZONE 6
END
SWITCH
MOTOR
ON OFF
ON OFF
L
SYSTEM
PUMP
N
MASTER SLAVE
VENT
L
N
PRIORITY!
pump
SECONDARY!
pump
ZV1 ZV4ZV3ZV2 ZV5 ZV6
ZV1 ZV4ZV3ZV2 ZV5 ZV6
PRIORITY!
pump
SECONDARY!
pump
mod/con!
boiler
Please reference Z-one™ Relay wiring guide for complete listing of wiring diagrams.
ModCon boiler with
Primary/Secondary

L
N
G
T T
ZR
ZC
outdoor!
temperature!
sensor
boiler!
reset!
controller 6 Zone
Z6V
THM 2
C
RW
T T COM COMMS
DP
DHW
ZR/ZC
X X
THM 3
C
RW
T T COM
THM 1
C
RW
T T COM
L
POWER IN
N
THM 4
C
RW
T T COM
THM 5
C
RW
T T COM
THM 6
C
RW
T T COM PWR
THM1 ZONE1
THM2 ZONE2
THM3 ZONE3
THM4 ZONE4
THM5 ZONE5
THM6 ZONE6
L
PRIORITY
PUMP
NL
SEC PUMP
N
SYSTEM
PUMP
STATUS
DURING
PRIORITY
ZONE 1
END
SWITCH
MOTOR
PRIORITY
ZONE 2
END
SWITCH
MOTOR
ZONE 3
END
SWITCH
MOTOR
ZONE 4
END
SWITCH
MOTOR
ZONE 5
END
SWITCH
MOTOR
ZONE 6
END
SWITCH
MOTOR
Master/Slave
space heating thermostats
DHW!
aquastat
space
heating
demand
domestic water
heating demand
SYSTEM!
pump
L N G
ZV1 ZV2 ZV4 ZV5 ZV6ZV3
set to ON
indirect DHW tank
DHW!
aquastat
VENT
low flow resistance boiler
ZV1
ZV2 ZV4 ZV5 ZV6 ZV3
SYSTEM!
pump
ZRV106
Noncondensing boiler with
outdoor reset and indirect DHW

Caleffi North America, Inc.
3883 West Milwaukee Road
Milwaukee, WI 53208
T: 414.238.2360 F: 414.238.2366
CALEFFI
6 Zone
ZVR106
T-STAT 2
C
RW
T T COM COMMS
DP
DHW
ZR/ZC
X X
T-STAT 3
C
RW
T T COM
T-STAT 1
C
RW
T T COM
L
POWER IN
N
T-STAT 4
C
RW
T T COM
T-STAT 5
C
RW
T T COM
T-STAT 6
C
RW
T T COM PWR
TSAT1 ZONE1
TSAT2 ZONE2
TSAT3 ZONE3
TSAT4 ZONE4
TSAT5 ZONE5
TSAT6 ZONE6
L
PRIORITY
PUMP
NL
SEC PUMP
N
STATUS
DURING
PRIORITY
ZONE 1
END
SWITCH
MOTOR
PRIORITY
ZONE 2
END
SWITCH
MOTOR
ZONE 3
END
SWITCH
MOTOR
ZONE 4
END
SWITCH
MOTOR
ZONE 5
END
SWITCH
MOTOR
ZONE 6
END
SWITCH
MOTOR
ON OFF
ON OFF
L
SYSTEM
PUMP
N
MASTER SLAVE
L
N
"A"!
pump
SYSTEM!
pump
A4A3A2 A5 A6
"B"!
pump
6 Zone
ZVR106
T-STAT 2
C
RW
T T COM COMMS
DP
DHW
ZR/ZC
X X
T-STAT 3
C
RW
T T COM
T-STAT 1
C
RW
T T COM
L
POWER IN
N
T-STAT 4
C
RW
T T COM
T-STAT 5
C
RW
T T COM
T-STAT 6
C
RW
T T COM PWR
TSAT1 ZONE1
TSAT2 ZONE2
TSAT3 ZONE3
TSAT4 ZONE4
TSAT5 ZONE5
TSAT6 ZONE6
L
PRIORITY
PUMP
NL
SEC PUMP
N
STATUS
DURING
PRIORITY
ZONE 1
END
SWITCH
MOTOR
PRIORITY
ZONE 2
END
SWITCH
MOTOR
ZONE 3
END
SWITCH
MOTOR
ZONE 4
END
SWITCH
MOTOR
ZONE 5
END
SWITCH
MOTOR
ZONE 6
END
SWITCH
MOTOR
ON OFF
ON OFF
L
SYSTEM
PUMP
N
MASTER SLAVE
SYSTEM!
pump
"A"!
pump
"B"!
pump
A1 A10A9A8 A11 A12A7
A4A3A2 A5 A6A1 A10A9A8 A11 A12A7
Modern boiler with Primary/Secondary and
two secondary pumps

WIRING GUIDE
4009064
Certified to CSA C22-2 No.24
Conforms to UL Standard 873
The ZSR101 is a versatile single relay control with two outputs for operating a 120 VAC pump with boiler enable, or two 120
VAC devices without boiler enable. Features include rear knock outs for 4x4 junction box mounting, convenient pre-installed
jumper for pump operation, and 10 amp total load rating.
The ZSR Series of controls is for zoning using pumps. Up to 6 zone pumps (model dependent) along with a primary pump
can be operated. Zone priority is selectable with 1-hour time-out feature. Other features include pump exercising, selectable
post purge, and 3 pump ground terminals for simplifi ed wiring.
The ZVR Series of controls is for zoning using zone valves. Up to 6 valves (model dependent), along with a system pump,
secondary pump(s), and primary pump can be operated. Zone priority is selectable with 1-hour time-out feature. System
pump status (on\off) during priority is also selectable. Replaceable snap-fi t 40 VA transformer standard for 3 & 4 zone mod-
els – expandable to 80 VA with 2nd transformer. 6 zone model has two 40 VA (80 VA) transformers.
Form 031914 rev.1

2
INDEX
Z-one Relay thermostat connections
Thermostat wiring ........................................................................................................................................................................... 3
ZSR101 - single zone relay
Product overview ............................................................................................................................................................................ 4
Operation and cover removal ........................................................................................................................................................................5
A1 - Single thermostat ...................................................................................................................................................................................6
A2 - Multiple thermostats....................................................................................................................................................................8
A3 - Single master thermostat, with TRVs, variable speed pump.................................................................................................... 10
ZSR103, ZSR104 & ZSR106 - multi-zone pump relay
Product overview ........................................................................................................................................................................... 12
Circuit board .................................................................................................................................................................................. 13
Cover removal................................................................................................................................................................................ 14
Product details............................................................................................................................................................................... 15
B1 - Mod/Con boiler, hydro separator or buffer tank, zone pumps ................................................................................................. 16
B2 - Traditional boiler, indirect DHW w/ priority, zone pumps .......................................................................................................... 18
B3 - Mod/Con boiler, primary loop, closely spaced tees, zone pumps............................................................................................ 20
ZVR103, ZVR104 & ZVR106 - multi-zone valve control
Product overview ........................................................................................................................................................................... 22
Circuit board .................................................................................................................................................................................. 23
Cover removal, Transformer Installation .................................................................................................................................................24
Product details............................................................................................................................................................................... 25
C1 - Mod/Con boiler, hydro separator, zone valves ........................................................................................................................ 26
C2 - Mod/Con boiler, indirect DHW on primary side of hydro sep, zone valves ............................................................................... 28
C3 - Mod/Con boiler, indirect DHW on load side of hydro sep, zone valves.................................................................................... 30
C4 - Mod/Con boiler, indirect DHW on primary side of hydro sep, master and slave control........................................................... 32
C5 - Traditional boiler, indirect DHW (no priority) with valve............................................................................................................. 34
C6 - Traditional boiler with reset control, priority indirect DHW with valve........................................................................................ 36
C7 - Mod/Con boiler, hydro separator, zone valve (more than 6), multiple secondary pumps.......................................................... 38
Caleffi shall not be liable for damages resulting from misapplication or misuse of it products.

3
All Caleffi Z-one controls use the same interface
to connect to thermostats. This interface is
very flexible and allows many different types
of thermostats to be connected to the control
including 2, 3 and 4 wire versions. In addition, any
type of switching device can be used to signal a
heat demand by connecting the R & W (T & T)
terminals together. The terminals are dual labeled
to help simplify wiring.
Z-one Thermostat Connections
6 Zone
T-STAT 2
C
RW
T T COM
COMMS
DP
DHW
ZR/ZC
X X
T-STAT 3
C
RW
T T COM
T-STAT 1
C
RW
T T COM
L
PUMP 2
N
PRIMARY
PUMP
L
PRIORITY
PUMP 1
N
LPOWER IN
NGROUNDS
L
PUMP 3
N
TRANSFORMER
LN
T-STAT 4
C
RW
T T
COM
L
PUMP 4
NL
PUMP 5
NL
PUMP 6
N
T-STAT 5
C
RW
T T COM T-STAT 6
C
RW
T T COM PWR
ZONE1
ZONE2
ZONE3
ZONE4
ZONE5
ZONE6
DipSwitches
Master Slave
Priority OFF Priority ON
Primary OFF Primary ON
Exercise OFF Exercise ON
Post Purge OFF Post Purge ON
ZSR106
Z-one T-stat interface
Description
R = 24 VAC Supply
W = Heat Call
C = 24 VAC Common
Function
R&W: When connected, signals a heat demand.
R&C: Provides 24 VAC to powered thermostats.
There are a few different types of 2 wire thermostats
including bi-metallic, power stealing and battery
powered. All of these thermostats connect in
the same manner to the Caleffi Z-one series of
controls. Connect R to R and W to W. See below.
2-Wire Thermostats
6 Zone
Z6P
T
HM 2
C
R
W
T
T COM COMMS
DP
DHW
ZR/ZC
X X
THM 3
C
RW
T T COM
THM 1
C
RW
T T COM
L
PUMP 2
N
PRIMARY
PUMP
L
PRIORITY
PUMP 1
N
L
POWER IN
N
GROUNDS
L
PUMP 3
N
TRANSFORMER
12/20VA
LN
THM 4
C
RW
T T COM
L
PUMP 4
NL
PUMP 5
NL
PUMP 6
N
THM 5
C
RW
T T COM
THM 6
C
RW
T T COM
PWR
ZONE1
ZONE2
ZONE3
ZONE4
ZONE5
ZONE6
DipSwitches
Master Slave
Priority OFF Priority ON
Primary OFF Primary ON
Exercise OFF Exercise ON
Post Purge OFF Post Purge ON
To connect a 4-wire thermostat to the Z-one
series controls, connect R to R, W to W and C
to C. A jumper in the thermostat is also required
between R & Rh as shown below. Similar to a
3-wire thermostat, R & C from the Z-one Control
supply constant 24 VAC to the thermostat.
4-Wire Thermostats
Three wire thermostats get their power from the
control they are connected to. R & C from the
Z-one Control supply 24 VAC to the thermostat at
all times while the W lead signals a heat demand.
3-Wire Thermostats
6 Zone
Z6P
TH
M 2
C
R
W
T
T COM COMMS
DP
DHW
ZR/ZC
X X
THM 3
C
RW
T T COM
THM 1
C
RW
T T COM
L
PUMP 2
N
PRIMARY
PUMP
L
PRIORITY
PUMP 1
N
L
POWER IN
N
GROUNDS
L
PUMP 3
N
TRANSFORMER
12/20VA
LN
THM 4
C
RW
T T COM
L
PUMP 4
NL
PUMP 5
NL
PUMP 6
N
THM 5
C
RW
T T COM
THM 6
C
RW
T T COM
PWR
ZONE1
ZONE2
ZONE3
ZONE4
ZONE5
ZONE6
DipSwitches
Master Slave
Priority OFF Priority ON
Primary OFF Primary ON
Exercise OFF Exercise ON
Post Purge OFF Post Purge ON
6 Zone
Z6P
TH
M 2
C
R
W
T
T COM COMMS
DP
DHW
ZR/ZC
X X
THM 3
C
RW
T T COM
THM 1
C
RW
T T COM
L
PUMP 2
N
PRIMARY
PUMP
L
PRIORITY
PUMP 1
N
L
POWER IN
N
GROUNDS
L
PUMP 3
N
TRANSFORMER
12/20VA
LN
THM 4
C
RW
T T COM
L
PUMP 4
NL
PUMP 5
NL
PUMP 6
N
THM 5
C
RW
T T COM
THM 6
C
RW
T T COM
PWR
ZONE1
ZONE2
ZONE3
ZONE4
ZONE5
ZONE6
DipSwitches
Master Slave
Priority OFF Priority ON
Primary OFF Primary ON
Exercise OFF Exercise ON
Post Purge OFF Post Purge ON
6 Zone
Z6P
THM 2
C
RW
T T COM
COMMS
DP
DHW
ZR/ZC
X X
THM
3
C
RW
T T
COM
THM 1
C
RW
T T COM
L
PUMP 2
N
PRIMARY
PUMP
L
PRIORITY
PUMP 1
N
L
POWER IN
N
GROUNDS
L
PUMP 3
N
TRANSFORMER
12/20VA
LN
THM 4
C
RW
T T COM
L
PUMP 4
NL
PUMP 5
NL
PUMP 6
N
THM 5
C
RW
T T COM
THM 6
C
RW
T T COM P
WR
ZONE1
ZONE2
ZONE3
ZONE4
ZONE5
ZONE6
DipSwitches
Master Slave
Priority OFF Priority ON
Primary OFF Primary ON
Exercise OFF Exercise ON
Post Purge OFF Post Purge ON
C R Rh W1
A heat demand can also be initiated by any type
of device that has dry contacts (dry contacts are
a set of contacts that open and close but do not
have any voltage present until supplied from an
outside source). The end switch on a Z-one series
zone valve is an example of a dry contact. Using
a dry contact to connect R to W will initiate a heat
demand.
Dry Contacts
Always refer to the thermostat manufacturer’s instructions.
SAFETY INSTRUCTION
This safety alert symbol will be used in this manual to draw attention to safety
related instructions. When used, the safety alert symbol means ATTENTION!
BECOME ALERT! YOUR SAFETY IS INVOLVED! FAILURE TO FOLLOW THESE
INSTRUCTIONS MAY RESULT IN A SAFETY HAZARD.
CAUTION: All work must be performed by qualified personnel trained in the
proper application, installation, and maintenance of systems in accordance with all
applicable codes and ordinances.
CAUTION: Electrical shock hazard. Disconnect power before installation to prevent
electrical shock or equipment damage. Make sure all connections are in accordance
with the electrical wiring diagram and in accordance with national and local electrical
codes.
CAUTION: Avoid electrical noise interference. Do not install near large conductors,
electrical machinery, or welding equipment. Avoid locations where excessive
moisture, corrosive fumes, vibration, or explosive vapors are present.
Caleffi shall not be liable for damages resulting from misapplication or misuse of it products.
WARNING: NEVER CONNECT R & C DIRECTLY,
this will be a direct short on the 24 VAC supply

4
Overview
•Compatiblewith2,3and4-wirethermostatsorother
low voltage controllers with switching action
•120VACinput
•Heavyduty,sealed,DPDT,fuseprotectedrelay 
(with spare fuse)
•Twodrycontactoutputs(Relay1andRelay2)for
operating 120 VAC pump with boiler enable or two
devices without boiler enable
•5Acapacityeachrelay-10Atotal
•Rearknock-outsformountingonto4”x4”junctionbox
•Highcapacity6VAtransformer
•Simplifiedwiringwithpre-installedjumper
•100%factorytestedwith3yearwarranty
•ETLcertified
See technical brochure 01284-14 NA for more product
information.
4009064
Certified to CSA C22-2 No.24
Conforms to UL Standard 873
ZSR101 - Single Zone Switching Relay

5
When a zone has a
demand from a thermostat
(TT or R W) the relay will
close sending 120 VAC
to Relay #1 NO terminal
and switching the pump
on, and the C to NO dry
contact on relay #2 closes,
signaling the boiler of a heating demand.
1 Zone
ZSR101
C
RW
T T COM
L
POWER IN
NC
RELAY #1
NO NC C
RELAY #2
NO NC
TRANSFORMER
PWR
ZONE
1 Zone
ZSR101
C
RW
T T COM
L
POWER IN
NCRELAY #1
NO NC CRELAY #2 NO NC
TRANSFORMER
PWR
ZONE
Operating Principles
R, W, C and T T Comm dual labeling at thermostat terminals.
Compatible with low voltage 2, 3, or 4 wire thermostats or any
other low voltage devices having a switching action.
Supply 120 VAC hot to terminal L and 120 VAC neutral to N.
A factory installed jumper from L terminal to the C terminal of
Relay 1 is supplied for simplified pump connection.
Dual labeled T-stat terminals.
Compatible with 2, 3 and 4
wire T-stats.
Replaceable fuses.
6 VA Transformer.
Keyhole mounting
which fits a 4X4
junction box.
Pre-installed jumper. Rear knockout for
4X4 junction box.
If dry contacts are desired from relay #1, remove the factory
installed jumper between L and C.
Cover removal
Hold either the left or the right end
of the box up and at an angle. Use
body for stabilizing relay box. Insert
screwdriver and push tab inward.
Turn box and repeat inserting
screwdriver and pushin tab inward on
opposite side, cover should release
from base.
Slide cover off base.
Mounting: Do not mount to a
surface that exceeds 115°F (45°C).
The unit must be only located in dry
interior locations. Use only copper
conductor supply wire suitable for
at least 105° C. All circuits must
have a common disconnect and
be connected to the same pole of
the disconnect. It is not suitable for
installation in hazardous locations.
120VAC input
power connection

6
T
T
RWC
TTcom
power
zone
transformer
N LL RELAY 1
C N/O N/C C N/O N/C
RELAY 2
CalefÞ!
single zone relay
L
N
A1 - Single thermostat
Hydronic diagram is for illustration purposes only, some components have been removed for simplicity.

7
Sequence of Operation / Settings
• A demand occurs and closes RW (TT)
• Relay #1 and relay #2 both fire connecting the
common terminal to the NO terminal.
• If the factory installed jumper has not been
removed, the NO terminal of relay #1 will
deliver the hot leg of 120 VAC. Relay #2 has
dry contacts.
• The zone LED illuminates.
• The demand is satisfied and opens RW (TT).
• The relay contacts return to their normal
position (common to normally closed).
• The zone LED turns off.
Description of terminals
= Ground
N = Neutral (Common leg of 120 VAC)
L = Line (live leg of 120 VAC)
C = Common terminal
NO = Normally Open terminal
NC = Normally Closed terminal
Note: There is a factory installed jumper between the 120
VAC line (L) and the common terminal of relay #1 (C).
Thermostat terminals
R = 24 VAC
W = Heat call
C = Common of 24 VAC
WARNING: NEVER CONNECT R & C DIRECTLY,
this will be a direct short on the 24 VAC supply

8
RWC
TTcom
power
zone
transformer
N LL RELAY 1
C N/O N/C C N/O N/C
RELAY 2
CalefÞ!
single zone relay
4-wire zone valve 4-wire zone valve 4-wire zone valve
R W
24 VAC
T
T
RWRW
End switch wires
L
N
A2 - Multiple thermostats
Hydronic diagram is for illustration purposes only and could be missing system components.

9
Sequence of Operation / Settings
• There is a demand by one of the t-stats which
sends power to the corresponding zone valve.
• When the zone valve opens, its end switch
contacts close and signal a demand to the RW
(TT) contacts on the single zone relay control.
• Relay #1 and relay #2 fire
• If the factory installed jumper has not been
removed, the NO terminal of relay #1 will
deliver the hot leg of 120 VAC thus firing the
pump.
• Relay #2 closes the TT contacts on the boiler
signally a demand.
• The Zone LED illuminates.
• When the last of the T-stats is satisfied, the
corresponding zone valves closes which
opens the end switch contacts.
• The relay contacts return to their normal
position turning off power to the system pump
and opening the RW (TT) contacts.
• The Zone LED turns off.
WARNING: NEVER CONNECT R & C DIRECTLY,
this will be a direct short on the 24 VAC supply
Description of terminals
= Ground
N = Neutral (Common leg of 120 VAC)
L = Line (live leg of 120 VAC)
C = Common terminal
NO = Normally Open terminal
NC = Normally Closed terminal
Note: There is a factory installed jumper between the 120
VAC line (L) and the common terminal of relay #1 (C).
Thermostat terminals
R = 24 VAC
W = Heat call
C = Common of 24 VAC

10
buffer tank
thermostatic!
radiator valves!
(TRV) on each!
radiator
TRV
TRV
TRV
TRV
TRV TRV
RWC
TTcom
power
zone
transformer
N LL RELAY 1
C N/ON/C C N/ON/C
RELAY 2
CalefÞ!
single zone relay
T
T
L
N
A3 - Single master thermostat, panel radiators with TRVs, variable speed pump
Hydronic diagram is for illustration purposes only, some components have been removed for simplicity.

11
Sequence of Operation / Settings
• A single “master” thermostat is wired to the
ZSR101 control. The master thermostat is set
to a slightly higher set point than the desired
room temperatures on the thermostatic
radiator valves.
• When the temperature drops below the
thermostat’s set point, a heat demand is
initiated by closing the R & W terminals.
• Relay #1 and relay #2 both fire.
• If the factory installed jumper has not been
removed, the NO terminal of relay #1 will
deliver 120 VAC line to the variable speed
circulator.
• Relay #2 closes the TT contacts on the boiler
signaling a demand.
• The Zone LED illuminates.
• Using an outside air sensor and system
temperature sensor located in the buffer tank,
the boiler determines if the water in the boiler
meets the target temperature based off the
outside air reset curve.
• As long as the master thermostat is calling,
the boiler will maintain the buffer tank to the
target temperature.
• The thermostatic radiator valves modulate the
flow through the panel radiators because the
variable speed circulator is enabled.
• When the master thermostat reaches set
point, the master thermostat will open the
contact between R & W.
• The relay contacts return to their normal
position turning off power to the variable
speed circulator and opening the RW (TT)
contacts. Both the boiler and pump are
no longer enabled.
• The Zone LED turns off.
WARNING: NEVER CONNECT R & C DIRECTLY,
this will be a direct short on the 24 VAC supply
Description of terminals
= Ground
N = Neutral (Common leg of 120 VAC)
L = Line (live leg of 120 VAC)
C = Common terminal
NO = Normally Open terminal
NC = Normally Closed terminal
Note: There is a factory installed jumper between the 120
VAC line (L) and the common terminal of relay #1 (C).
Thermostat terminals
R = 24 VAC
W = Heat call
C = Common of 24 VAC

12
ZSR10X - Multi-Zone Pump Control
Overview
• Compatible with low voltage 2, 3, or 4 wire
thermostats
• R, W, C and TT Comm dual labeling at thermostat
terminals
• Z-oneLink unlimited zone expansion
• 120 VAC pump outputs
• Selectable priority with 1 hour time-out feature
• Selectable post purge and exercise
• Dry contacts for DHW (ZR/ZC), capable of switching
line voltage
• High capacity transformer
• Large terminal connections
• Simplified wiring with extra ground terminals
• Heavy duty sealed relays
• Fuse protected (with spare fuse)
• Front LED lights
• 100%Factorytestedwith3yearwarranty
• ETL approved
See technical brochure 01286-14 NA for more product
information.
4009064
Certified to CSA C22-2 No.24
Conforms to UL Standard 873