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Sequence of Operation / Settings
Priority switch: ON (Zone #1 becomes priority)
Master/Slave switch: Master
Primary Status During Priority switch: OFF
•
A demand occurs from a T-stat (T-stat closes
TT terminals) in zones 2 thru 6.
• The “PUMP ON” LED illuminates for that zone.
•
ZSR control sends 120 VAC to the
corresponding zone pump terminals to fire
the zone pump and closes the XX contacts
to signal a heat demand to the boiler. The
PRIMARY PUMP output will also deliver 120
VAC even if no pump is connected.
•
When the demand from the T-stat is satisfied
(T-stat opens TT terminals), the “PUMP ON”
LED turns off.
•
120 VAC is dropped from the corresponding
zone pump terminals.
•
If no other zones are calling, power is dropped
to the SEC PUMP and SYSTEM PUMP and
the XX contacts are opened.
•
If a demand occurs from the DHW aquastat
(zone #1), The “PUMP ON” LED illuminates for
Zone #1.
•
If any other zone was calling (Zones 2 thru
6) when Zone #1 called, power (120 VAC) is
dropped to those zone pumps.
•
The XX and DHW contacts close.
•
The PRIORITY PUMP contacts deliver 120
VAC
•
Once the Zone #1 DHW demand is satisfied,
power to the PRIORITY PUMP is dropped, the
DHW contacts open.
•
If a demand from zones 2 thru 6 is present,
120 VAC is delivered to the corresponding
zone pump(s) and the “PUMP ON” LED for
those zones will illuminate.
•
The XX contacts close to signal a heat demand
to the boiler.
•
When all zones are satisfied, the XX contacts
open and power (120 VAC) is turned off to all
of the zone pumps.
DHW Time Out \ Freeze Prevention Feature
•
After one hour of a priority demand, the control
will open the DHW contacts and turn off power
to the DHW pump.
•
If a heating demand is present from Zones
#2- 6, the control will satisfy those demands
before going back to the DHW call.
•
After the heating demands are met, the control
will go back to DHW and re-set the one hour
timer.
Description of terminals
= Ground
N
= Neutral (Common leg of 120 VAC)
L
= Line (Hot leg of 120 VAC)
Thermostat terminals
R = 24 VAC
W = Heat call
C = Common of 24 VAC
Boiler terminals
XX = Dry contacts rated up to 120 VAC, 2 Amps.
Closes when any zone calls including priority.
Typically connected to TT on boiler control.
DHW (ZR/ZC) = Dry contacts rated up to 120 VAC,
2 Amps. Closes only when priority is enabled and
calling. Typically used to close ZR\ZC (120 VAC)
or DHW contacts (24 VAC) on boiler controls
equipped with these features.
Dip switch description
Master / Slave: Used when joining 2 or more
controls together. Only one Master per group
Priority OFF / Priority ON: Used to set Zone #1
as the priority zone. All other zones will hold off
during priority. Priority has a one hour time out
feature to prevent freeze up.
Primary OFF / Primary ON: Sets the status of the
primary pump when there is a priority call. This
allows the DHW pump to be on either side of a
hydro separator.
Exercise OFF / Exercise ON: When enabled the
pumps will rub for 30 seconds after 72 hours
without a demand.
Post Purge OFF / Post Purge ON: Allows the DHW
pump to run for 2 minutes after the DHW demand
has been satisfied.
WARNING:
NEVER CONNECT R & C DIRECTLY,
this will be a direct short on the 24 VAC supply
