Atag i28C Technical Guide

ATAG 3-port external diverter valve kit
including the ONE
ZONE
controller or Cube used with a vented hot water cylinder
(iS System boiler only)
Vented hot water cylinders
The ATAG 3-port diverter valve is to be fitted external
to the boiler on the system pipework with the electrical
wiring routed back to the 3 way valve electrical connection
on the back of the PCB housing.
The installation will use the cylinder sensor supplied
within the 3-port diverter valve kit to control the hot water
temperature. Therefore no other cylinder thermostat is
required.
The ONE
ZONE
controller will control the heating and hot
water time and temperature requirements. If the cube
room thermostat is used then the heating and hot water
times are controlled on the boilers built in programmer
option.
The weather compensation for heating will be controlled
by the boiler and ONE
ZONE
controller via the internet
connection and local weather station data. An optional
outside sensor (ARZ0055U) can be added to the 3-port
diverter valve kit to sense the outside temperature
specifically for the individual property.
With an ATAG Cube fitted the optional outside sensor
would be needed if weather compensation was required
for the central heating.
When put into heating mode the diverter is powered.
Brown & Blue 230V, Black & Blue 0V.
When put in hot water mode there is a switch of power.
Brown & Blue 230V, Black & Blue 230V.
So, hot water power put on Black & Blue, heating power
taken o Black & Blue.
The ATAG 3-port diverter valve
Install the 3-port valve on the system pipework with the valve ports in the following orientation, AB port iS System boiler,
A port hot water cylinder and B port heating system (see diagram on page opposite).
L
N
L
I
PE
N
PE
L
N
L’
230V out
230V Control
PE
N
L
230V in
N
L
230V out
L
N
L
I
3-PORT VALVE
230V
Connection 3 way valve
L:
Live
N:
Neutral
L':
Signal DHW
52

Atag i28C Specifications

General

Brand	Atag
Model	i28C
Category	Boiler
Language	English