WaterFurnace Envision Hydronic (NSW) - Manual (Page 25)

25
NSW INSTALLATION MANUAL
Staging with Primary/Secondary Mode
Staging is only possible with dedicated heating or cooling
units. Reversible units cannot be staged. Staging can be
accomplished with primary/secondary modes or by using
an aquastat.
The first stage must be setup as a primary unit. All other
units must be setup as secondary units. The set point is
stored in the primary unit. Once the set point in the primary
unit has been satisfied, all units will immediately shutdown.
WARNING: Do not stage more than 6 units.
C
G
W1
L
X1
Y2
O
Y1
W2
S
X2
R
C
G
W1
L
X1
Y2
O
Y1
W2
S
X2
R
C
G
W1
L
X1
Y2
O
Y1
W2
S
X2
R
Wiring for Primary/Secondary Unit Staging
First Stage Second Stage Third Stage
NOTES: X1 = Secondary output
Y1 = Compressor call
Staging with Aquastat
When staging units using an Aquastat, all units must be
setup as secondary units.
WARNING: Do not stage more than 6 units.
( )
C
G
W1
L
X1
Y2
O
Y1
W2
S
X2
R
C
G
W1
L
X1
Y2
O
Y1
W2
S
X2
R
Typical Aquastat
Wiring for Dedicated Heating or Cooling Units
with Aquastat
First Stage Second Stage
NOTES: X1 = Secondary output
Y1 = Compressor call
R = 24 VAC
External Control cont.