Baxi HT 1.850 Installation, Operation And Maintenance Manual page 23

c) with AGU2.500 for control of a low temperature system:
Refer to the instructions provided with the AGU2.500 accessories for connection and control of a low tem-
perature zone.
In this case some electronic parameters must be modi ed (see §14) (H552-H553-H632).
The electrical connection and settings needed to control a system divided into zones vary depending on the
accessories connected to the boiler.
a) Without QAA73 room temperature control device:
The contact relating to the request for operation of the various zones must be parallel-connected and connected
to terminal 3-4 "TA" of terminal block M2 in gure 10. The jumper present must be removed.
The central heating temperature is selected directly on the boiler control panel in accordance with the instruc-
tions provided for the user in this manual.
b) with QAA73 room temperature control device:
The pump relating to the room controlled by the QAA73 temperature control device must be supplied with
electricity by means of terminals 11-12 of terminal block M3 in gure 10.
The contact relating to the request for operation of the other zones must be parallel-connected and connected
to terminal 3-4 "TA" of terminal block M2 in gure 10. The jumper present must be removed.
The central heating temperature of the zone controlled by the QAA73 is set automatically by the QAA73 itself.
The central heating temperature of the other zones must be selected directly on the boiler control panel.
In this case some electronic parameters must be modi ed:
H552 = 50, H632 = 00001111.
Figure 10
c) with AGU2.500 for control of a low temperature system:
Refer to the instructions provided with the AGU2.500 accessories for connection and control of a low tem-
perature zone.
In this case some electronic parameters must be modi ed (see §14) (H552-H553-H632).
ISTRUCTIONS PERTAINING TO THE INSTALLER
hydroheat.com.au
12.6 CONNECTING A ZONE SYSTEM
2 ZONE
BOILER
(ROOM THERMOSTAT)
CIRCULATING
PUMP
HEATING CUT-OUT
RELAY
23
3 ZONE
n ZONE
(ROOM THERMOSTAT)
(ROOM THERMOSTAT)
2 ZONE- 3 ZONE- N ZONE-
PUMP PUMP PUMP
BOILER
1 ZONE
PUMP
(QAA73)
1 ZONE PUMP
910.026.1 - EN (AUS)