cm10 S2 and Rotel RX-1050 when bi-wired on A and B speakers Rotel overheats easily

got B&W cm10 to replace 686 and started by bi-wiring them using A and B speakers. But the receiver overheats and turns itself off. It is 100W per channel which I thought would be enough. I went to regular wiring, receiver gets warm but does not overheat.
thanks in advance.
Probably because speaker b is a parallel amp channel to speaker a. In order to actually BiAmp you would need to add an external 2ch amp.

Also a lack of ventilation and air flow will create a large amount of heat
Thanks for your response.
there is no lack of ventilation or air flow. I do have another receiver I could hook up but I am not sure how to do it.
Here is the pic of the back of my receiver, the one that overheats.
I wouldn't run the B&W CM10 off an AV receiver and plus your Rotel RX1050 receiver is very old and it's time to upgrade to a new AV receiver if you want to stick with a receiver. Rotel's new current flagship AV receiver the RAP-1580 is phenomenal and I would highly recommend that with your B&W CM10. Other great quality AV receivers to consider are : Arcam AVR850, AVR550, Audio Control Maestro, Marantz SR8012, NAD T787 (recently discontinued I think). 

But if you aren't doing surrounds I would highly recommend good quality stereo integrated amp or stereo separates.