Technical data
60
CTC EcoZenith i250 
Installation
01  CTC EcoZenith i250
B1  Primary flow sensor for radiator system 1
B2  Primary flow sensor for radiator system 2
B5  Sensor upper tank
B6  Sensor lower tank
B7  Sensor, radiator return
B11 Room sensor 1
B12 Room sensor 2
B15 Outdoor sensor
G1  Circulation pump, radiator system 1
G2  Circulation pump, radiator system 2
Y1  Mixing valve, bivalent radiator system
Y2  Mixing valve, radiator system 2
11  Radiator system 1
12  Radiator system 2 
47  Electric shut-off valve for radiator system
48  Non-return valve for incoming cold water
65  Mixing valve for DHW 
90  Filling valve, radiator system
91  Adjustment valves for radiator coils
92  Boiler safety valve (factory-installed), 2.5 bar
93  Safety valve for DHW
94  Shut-off valve
95  System/boiler pressure installed on return pipe
P
01
B5
Y1
B6
B11
B12
Cold water inlet
93
92
65
B1
48
12
B2
B7
Y2
90
B15
11
Exp
47
94
94
91
91
95
G1
G2
c
T
c
!
Radiator system 2 
can only give the 
same temperature as 
radiator system 1 or a 
lower temperature.
12.2  Schematic diagram
This shows the main connection between the CTC EcoZenith i250 and the property’s radiator and hot water system. 
Different installations and systems may look different, such as a one- or two-pipe system, which means that the 
finished installation may be different. 










