Eco Heating Systems CB 105 HW, Installation, Service And User Manual

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E93.1803.901 HW 45
Minimum required pump head.
To prevent calcification of the heat exchanger, the speed of the water needs to be high. The design flow of the
system should be at a delta T of 12.5 / 16.5 °C at high fire. To calculate the minimum required pump head, take
the resistance of the water heater and add the resistance of the piping and tank to make a good design.
Normally, an extra 2 m.WC of head is sufficient to overcome the resistance of the pipe and tank.
Water heater
ΔT = 12.5 °C at flow
rate
min. required head
for water heater
min. required head for
installation: +2 m.WC
[m
3
/h] [m.WC] [m.WC]
CB 85 HW 5.63 9.00 11.00
CB 105 HW 6.70 9.50 11.50
CB 125 HW 8.23 9.56 11.56
CB 155 HW 10.01 8.53 10.53
Water heater
ΔT = 16.5 °C at flow
rate
min. required head
for water heater
min. required head for
installation: +2 m.WC
[m
3
/h] [m.WC] [m.WC]
CB 85 HW 4.26 5.45 7.45
CB 105 HW 5.08 5.65 7.65
CB 125 HW 6.23 5.54 7.54
CB 155 HW 7.58 5.14 7.14
Pump: maximum electric power
General
- The inrush current of a conventional pump is approximately 2½ x its nominal current.
- The maximum allowed switch current of the burner controller is 2 A.
- So the maximum current of the connected pumps is 2 A. Nominal.
Your supplier can offer two different pumps
Pump number Pump type
1 Grundfos UPMXL GEO 25-125N 180
2 Wilo Stratos Para Z 25/1-12
Pump P1
meets this requirement. The pump main voltage connection can be directly connected to terminal 6-7-
PE of the mains voltage connection terminal. The PWM cable must be connected to terminal 18-19 of the low
voltage connection terminal.
Pump P2 has a high inrush current. Therefore it is not allowed to connect the main voltage connection of pump
P2 directly to the boiler terminals. Connect the pump main voltage connection directly to the external (wall socket
e.g.) main voltage. The PWM cable must be connected to terminal 18-19 of the low voltage connection terminal.