Laars FT Series - Zone Valve System Wiring; Zone Valve System Wiring Diagram

The FT Series Floor Standing, Combination Boiler
Page 47
T STAT 2
VALVE
2
POWER
T STAT 1
T STAT 3
VALVE
3
T STAT 4
VALVE
4
POWER IN
T T
ZONE 2
T T
ZONE 3
T T
ZONE 4
OFF
ON
END
SW.
MODE
FOUR ZONE ZONE VALVE CONTROL
WITH OPTIONAL PRIORITY
NORMAL RESET
SYSTEM 2 WIRING
THERMOSTAT THERMOSTAT
ZONE 1
1 2 34 1
ZONE 4 PRIORITY
2
ZVC 404
34
ZONE 2
1 2 34
ZONE 3
1 2 34
ZONE 4
3 WIRE ZONE VALVE
1
2
3
FUSE (3 AMP MAX)
24 VAC
INPUT
DRY
CONTACTS
N/0 C N/C
RW
TT
24
VAC
COM
POWER
T STST
N5H
THERMOSTAT
3
4
N/O
4
N/C
6
N/C
6
N/O
FUSE
5
A
FUSE
1
A
HI TEMP
AUXILIARY
ZONE
THERMOSTAT
SR501
TO
120 VAC
LNG NGLNG
OI
LOW VOLTAGE TERMINALS (18 Gauge Wire)
L/ZC
LINE VOLTAGE TERMINALS (14 Gauge Wire)
SYSTEM PUMP DHW RECIRC
MAIN POWER
120 VAC
LESS THAN
12 AMPS.
T T
ZONE 1
3 WIRE ZONE VALVE
1
2
3
3 WIRE ZONE VALVE
1
2
3
HIGH TEMP
ZONE PUMP
JUMPER
AC24V
OUTPUT
LWC
DHW
RECIRC.
SENSOR
H-T/T
O/S
R 0-10V W
(Factory Installed Jumper)
(+) INPUT (-)
T/T
VALVE 1
Wiring of zone valve system with an optional high temp “on demand” zone with dedicated pump.
1)
Taco ZVC 404 used for illustrative purposes; other, similar zone valve control panels can be used.
2)
Connect the end switch of the zone valve panel back to the T/T terminals on the FTCF boiler.
3)
Connect the system pump for the zone valves to the System Pump terminals.
4)
Connect the outdoor sensor (OS) to its terminals.
5)
Do not bring 24 V back to the T/T or H-T/T terminals on the FTCF boiler. Only a dry contact switch is allowed.
6)
In case an "on-demand" high temperature zone is required, use a single pump relay and wire its pump and
thermostat to this relay. The end switch is connected to the H-T/T terminals. A contact closure to H-T/T
brings the boiler into a high temperature status, operates the boiler pump continually and maintains the LLH
between 160 and 180 F.
Note:
While H-T/T is calling, other zones will still be allowed to demand heat and will therefore receive high
temperature supply water. Caution should be used with zones that could be damaged by high
temperature supply water such as radiant underoor zones. Zone mixing valves for these individual
zones is strongly encouraged.