Buderus 500-24C Installation And Maintenance Instructions Manual page 29

V Connect the two wires of cable from the ModuLink
receiver to terminal 1 and 2 of the connection block on
the back of the DBA (
polarity sensitive.
A green LED will light on the receiver, when installed
correctly and the boiler is reconnected to the mains
electricity supply.
There is no requirement to setup the RF link between the
thermostat and receiver. This has been completed as part
of the manufacturing process.
The room thermostat sends a signal to the receiver at
least every 30 minutes to see if they are still in contact
with each other.
V If you want to test whether you have reception then
press the button on the thermostat for more than
5 seconds. The thermostat will now send out a signal
continuously (The LED on the receiver flashes green
and the thermostat shows connecting in the display).
V The receiver will stay in this test mode until the
button on the thermostat is pressed.
V Raise and secure the DBA.
V Refit the boiler casing if necessary.
1.11.2 External 230 V controls
Caution:
This appliance must be earthed.
V Remove the securing screw and lower the DBA
( fig. 32).
V Using a screwdriver, remove the grey 230V cover
( fig. 38, item 1).
The grey 230V cover houses one fused circuit board.
The board has four terminals (
– L
OUT
– L
RTN
– N
OUT
– S
PARE
L & N are optional LIVE & NEUTRAL supplies from
OUT OUT
the boiler which are isolated via the on/off power switch
on the front of the DBA. If required, these can be used to
power a third party 230V thermostat / programmer etc.
Alternatively 230V controls can be powered from a sepa-
rate mains supply external to the boiler (i.e. L
terminals are not used).
Buderus 500-24C/28C - Subject to modifications resulting from technical improvements
fig. 37). The wires are not
fig. 39):
& N
OUT
Fig. 37 Room thermostat connection on DBA
1, 2 Room Thermostat
3 HW Tank Sensor
5 24 VAC
6, 7 3-Way Valve
Fig. 38 Room thermostat connection on DBA
OUT
Installation
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2
3
4
5
6
7
7215 3100-37.1TD
7215 3100-38.1TD
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