Checking The Control Unit; Connections To The Appliance - Buderus Logamax plus GB142-24 Installation And Servicing Instructions

14 Servicing
14.22 Checking the control unit;
connections to the appliance
If an On/Off thermostat is used and the appliance
does not react to a heat request:
Disconnect the heating system from the power
supply, remove the main fuse or switch off the circuit
breaker.
Set the main switch on the BC10 to "0" (Off).
Remove the casing.
Remove the cover from the connection box
(see fig. 89).
Use a jumper wire to create a bridging circuit
between the two "WA" contacts (see fig. 92, pos. 3).
Connect the heating system to the power supply,
insert the main fuse or switch on the circuit breaker.
Set the main switch on the BC10 to "1" (On).
If the appliance switches to heating mode (operating
code ) after some time, the cause of the fault
must be outside the appliance.
Disconnect the heating system from the power
supply, remove the main fuse or switch off the circuit
breaker.
Set the main switch on the BC10 to "0" (Off).
Remove the bridge between the two "WA" contacts
(see fig. 92, pos. 3).
Connect the On/Off thermostat directly to the two
"WA" contacts of the appliance using a short cable
(see fig. 92, pos. 3).
Connect the heating system to the power supply,
insert the main fuse or switch on the circuit breaker.
Set the main switch on the BC10 to "1" (On).
Set the On/Off thermostat to the request position.
If the appliance switches to heating operation (oper-
ating code ) after some time, the fault is caused
by the cable between the On/Off thermostat and the
appliance.
If the appliance does not switch to heating mode after
some time, the fault is caused by the On/Off thermo-
stat.
Correct the cause of the fault.
Fit the cover on the connection box (see fig. 90).
Fit the casing.
Connect the heating system to the power supply,
insert the main fuse or switch on the circuit breaker.
Set the main switch on the BC10 to "1" (On).
We reserve the right to make any changes due to technical modifications!
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Installation and Servicing Instructions Logamax plus GB142-24/30/45/60 • Version 12/2004
Fig. 89 Removing the cover from the connection box
Fig. 90 Installing the cover of the connection box
Buderus Hydronic Systems • http://www.buderus.net