How long can the Ed be left on before the power tubes go?

[danyeo1]

I was playing earlier today around 5:00pm. I had to run to do something for a few minutes, got side tracked, and forgot that I left the amp on. Around 10:00 I was watching TV upstairs and me and the wife heard something LOUD come from the basement. Didn't know what the hell it was. I went into the basement and smelled something bad. UGH OH, what could that be. Wasn't sure what it was but I noticed my amp was in the 90 watt setting, meaning I left it on all that time, but it was dead. And that's where the smell was coming from.

So I pulled out the fuse and it was fried. I threw another fuse in and the amp came back up in standby. *Sigh of relief* But I noticed 1 power tube was dead. Pulled it out and it had a white coating inside it. Threw another power tube back in and everything seems ok.

So, did it just run too hot or just a bad tube? Would it have been prevented if I had a fan blowing on the back of the amp?

 

[Hollis]

Man I've done that so many times with my Deluxe Reverb Reissue. I've come home from work only to realize that my amp is still on from the day before lol. I haven't yet done this with the Electradyne, so I don't know about it. I think you just had a typical tube failure. Although I do understand your concern, the Electradyne does get really hot!

 

[MrMarkIII]

Five hours. Apparently.
"White coating" means loss of vacuum. Tube gone bad.

 

[thunda1216]

Tubes fail. Some last decades, others hours. Were your power tubes JJ's?

 

[elvis]

I've played my amp 12 hours straight, so I know it can stay on that long. As long as it has a proper load and the input is not oscillating (guitar plugged in with volume down) should be able to go weeks or months left on.

You just had a power tube go bad.