Fitting a Siemens RDJ10Rf to a Baxi Duo Tech 33HE

18 Apr 2009
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United Kingdom
Can anyone please help with instructions to connect my Siemens receiver to the Baxi I've just had installed?

Heard that the stats and timers supplied by Baxi were rubbish, so opted for the easier to fit Siemens.

Problem is, the internal wiring for the Baxi 'optional timer' has four connections - Live, Neutral (numbered 3 + 1 in the wiring diagram which came with the boiler), and two switching connectors (numbered 2 + 4 in wiring diagram).

Whereas, the Siemens wiring diagram has Live, Neutral, LX (common), L1 (live feed to item to be controlled) and L2 (changeover contact).

Which of L1, LX and L2 should be connected to the switching connectors in the Baxi?

Help much appreciated.
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Page 32, fig 49/50, shows you all you need to know,

The switched connections in the siemens connect to the 'roomstat' terminals.

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