I have a H/K AVR 254. I recently had a problem with the receiver going into protect mode. I would hear a loud pop through the speakers and then the receiver would shut down. Eventually I lost the on-screen display. I tried soft reset, reset button on the back, everything recommended in FAQ's and could not get it to work. Harman/Kardon replaced the receiver no questions asked.
So now I have a new AVR 254 but I do not want to have the same problem. I believe there are 2 potential causes:
1. The receiver is seeing a short through the speakers. I had installed in wall speaker wire and terminals right before the trouble. Not sure if this is coincidence or not. I have checked resistance through all of the speakers/wires and get results between 6 and 8.5 Ohms. My in wall wiring does not register any resistance when the speakers are not connected. I think that confirms that I do not have a short, but would like feedback.
2. The receiver is getting too hot in my cabinet. I only have 3" above the reciever and less than 2" on either side. This was not a problem for my previous receiver but this is a much more powerful unit. Should I try to create more spacing for ventilation? And does this receiver really generate tons of heat? If I did have a short this sucker would run real hot and then shut down.....
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