Harman Kardon AVR 430 Cooling fan issue

[e30cabrio]

Anyone know when the fan is supposed to come on? Mine runs very hot to the touch and the fan does not come on. I connected the fan's power leads to a 6v wall wart and it works (cools it way down) but I am concerned that the circuit for the thermostat does not work (or if it has no thermostat then the fan circuit is faulty)

Anyone have a 430 that can tell me when the fan runs?

Thanks

 

[WndrBr3d]

The fan in the AVR430 may be running at a very-very low RPM as to be inaudible.

The owners manual says this about the fan:

It is normal for the fan to remain off at most normal volume levels. An automatic temperature sensor turns the fan on only when it is needed.

So unless you're pumping out a seriously loud sustained volume level, the fan probably wont turn on.

One think to keep in mind is that heat sinks will always be hot, the circuitry to activate the fan might be on the IC or the transistor itself.

Cheers!

 

[dillweed]

My HK 7300 fan runs very hard to keep everything cool. The fan turns on about a minute after turning the unit on regardless if I am listening to anything. I asked around awhile back if mine was the only one to do this and others told me that was normal for 7300. Fan can be pretty loud but only noticeable during quiet moments in a soundtrack. If no one with a avr 430 responds to you go to your local dealer and test the floor model.

 

[WndrBr3d]

My HK 7300 fan runs very hard to keep everything cool. The fan turns on about a minute after turning the unit on regardless if I am listening to anything. I asked around awhile back if mine was the only one to do this and others told me that was normal for 7300. Fan can be pretty loud but only noticeable during quiet moments in a soundtrack. If no one with a avr 430 responds to you go to your local dealer and test the floor model.

The fan function in the 7300 is different than that in the 430.

The fan in the AVR 430 is designed to cool the heatsinks for the transistors (they're laid horizontal and the fan blows the heat out the back).

The fan in the AVR 7300 is used to cool an IC or some circuit on a board much like that of a CPU Fan/Heatsink in a computer.

I'm guessing this is probably the FLI2300 processor that's being cooled, because it probably gets super hot inside the unit that passive cooling wouldn't have been an option.

 

[e30cabrio]

My fan didn't run ever. the unit was verging on painful to touch it was so hot. I opened it up (no I didn't connected a wall wart to the fan lead and now it is so cool it seems like it's off. I live in Mexico and risk having to pay duty on it again when I bring it back (after I lose it's use for god knows how long) so I decided to let it be for now as it works flawlessly otherwise.

Thanks

 

[e30cabrio]

I spoke to a technician at H/K today. He said to reduce noise (introduced into the circuitry) the fan is designed to come on only as a last resort if the unit is near bursting into flames. Since I am powering the fan now externally and it is very cool I think it will run for a very long time and I hear no degredation in the fidelity of the unit.

 

[e30cabrio]

I thought I would update that I have been using my 430 for over a year with it's fan externally powered and it still works like new and never gets hot.

Seeing as it is hot here and heat is bad for electronics I am sure I have extended it's lifespan.

 

[bbensten]

AVR 7300 FAN Help

Hello, I know this thread is old but I am having the same problem with my AVR 7300. The idea of connecting the 6volt power supply is very interesting but I cant even find the supply lead for the fan. It does not appear that my fan runs at all other then after a hard reset. Any help that anyone can provide is very much appreciated.