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• Connection diagrams
3110086 EHC20 UK 110515
O.8
Program 6.1.8. Heat exchanger with bypass damper. With two storage tanks and a mixer.
Smoke gas temperature
Storage tank
temperature
1
temperature
2
Storage tank
1
1
1
1
1
2
2
2
2
2
3
3
3
4
4
4
5
C
GND
GND
GND
GND
GND
GND
GND
GND
GND
GND
L
N
N
N
N
N
N
N
NC
NO
PE
PE
PE
PE
PE
PE
PE
PE
R1
R2
R3
R4
R5
R6
S1
S2
S3
S4
S5
S6
S7
S8
V1
V2
1
1
1
1
1
2
2
2
2
2
3
3
3
4
4
4
5
C
GND
GND
GND
GND
GND
GND
GND
GND
GND
GND
L
N
N
N
N
N
N
N
NC
NO
PE
PE
PE
PE
PE
PE
PE
PE
R1
R2
R3
R4
R5
R6
S1
S2
S3
S4
S5
S6
S7
S8
V1
V2
L
N
PE
L
N
PE
L
N
PE
L
N
PE
U
-S1
U
-S2
U
-S3
U
-S8
L1
N
P
E
L
N
PE
L
N
PE
CCW
CW
N
CCW
CW
N
Temperature sensor input 8
VFS2 sensors
V
FS
1
sensors
Mains
0-10V output
0-
10
V
output
exodraft EHC10/EHC20 controller
P
F
relay
Relay output
6
Relay output
1
RC plugs
C
A
N
C
A
N
Temperature sensor input
7
Temperature sensor input
6
Temperature sensor input
5
Temperature sensor input
4
Temperature sensor input
3
Temperature sensor input
2
Temperature sensor input
1
Relay output
5
Relay output
4
Relay output
3
Relay output
2
Bypass
3-way valve
Pump
Mixer
temperature
Forward flow
This diagram shows the following system:
Heat exchanger
with bypass
damper. Two storage tanks, a mixer, a 3-way valve and a circulator pump.
The S8 temperature sensor must be positioned in the heat exchanger inlet.
The S3 temperature sensor must be mounted on the forward flow pipe immediately after the heat exchanger.
The S2 temperature sensor must be mounted in storage tank #2.
The S1 temperature sensor must be mounted in storage tank #1.
The mixer should be controlled in such a way that R4 is enabled when the temperature in the forward flow pipe needs
to increase. R5 is enabled when the temperature needs to decrease.
R6 is enabled when the bypass damper is to switch to the non-bypass position.
Important:
An STL thermostat which turns off the burner must be mounted on the forward flow pipe. The forward flow
temperature must not exceed 100°C.
