CTC Union EcoZenith i550 Pro Installation And Maintenance Manual page 89

13.3.4 CTC EcoZenith i550 Pro - Domestic hot water
Figure 1 Shows how domestic hot water circulation can be connected to the
EcoZenith. The domestic hot water is circulated by pump (G40). New domestic
hot water from the finned coil is mixed in by the mixing valve (32), and cooled
water is released down to the coil for reheating. Only a part of one coil in the
upper tank is used for circulation. The non-return valves (22), (23), (33) and (34)
are needed to ensure that circulation proceeds as intended. The control valves
(28) and (29) make it possible to set the correct flow rate in the circuit.
Figure 2 Shows how an external DHW tank is connected. The manual
diverting valve (31) is set to allow domestic hot water to pass via the external
DHW tank. The sensor (B43) detects when the temperature drops in the
external DHW tank and starts the pump (G41). Cooled domestic hot water is
pumped via the non-return valve (35) and control valve (30) down to the part
of the coil used for circulation. The water is heated in the coil and is stored
in the external DHW tank. When the sensor (B43) reaches its setpoint, the
pump stops. The manual diverting valve is used to include or exclude the
external tank, as desired, in operation. When drawn off, the domestic hot
water passes through the entire coil and then via the external DHW tank.
The non-return valves (22), (23) and (35) are needed to ensure that circulation
proceeds as intended. The control valve (30) allows the desired flow of the
circuit to be adjusted.
See also Upper tank Menu in the Detail Description Menus chapter.
(Installer/Settings/Upper Tank)
Note that the safety valves for the tap water system are not entered in the
schematic diagrams.
Figure 1 Hot Water Circulation
G40
DHW TAPS
28
33
29
20
34
COLD
WATER
INLET
22
23
Figure 2 External DHW tank
32
COLD
WATER
INLET
For the installer
DHW TAPS
32
tº C
20
G41
30 35
B43
31
13
22
23
CTC EcoZenith i550 Pro 91