CALEFFI Z-one ZVR103 User Manual

13
Sequence of Operation / Settings
• A demand occurs from the thermostat closing
RtoWontheZSR101control.The“ZONE”
LED illuminates.
• The ZSR101 control will power relay #1 and
#2 closing C to NO.
• The NO terminal of relay #1 will send out
120 VAC to your pumps. Relay #2 provides
a dry contact closure to signal the boiler of a
demand.
• NOTE: Relay #1 can be used as a dry contact
as well by removing the factory installed
jumper between L and C.
• When the thermostat demand is satisfied R to
Wwillopenandthe“ZONE”LEDwillturnoff.
• The control will remove power from relays #1
and #2 opening C to NO. This will drop 120
VAC to your pumps and terminate the demand
to your boiler.
• NOTE: In this application, the single thermostat
will be set to a slightly higher temperature
than the desired room temperatures. The
room temperatures will then be controlled by
each individual thermostatic radiator valve
by adjusting the flow through the radiator
making this a fitting application for a variable
speed (ECM) pump (between the buffer tank
and radiators). When the temperature drops
below the set point of the thermostat the
boiler will maintain the buffer tank at its target
temperature. Ideally, the boiler will operate on
an outdoor reset curve to maximize efficiency
and use a system temperature sensor located
in the upper portion of the buffer tank.
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

CALEFFI Z-one ZVR103 Specifications

General

Brand	CALEFFI
Model	Z-one ZVR103
Category	Control Unit
Language	English