Carvin DCM1000 Protect light

[dagored11]

We have a Carvin DCM1000 power amp for our practice PA. Last week the fan went out, causing it to overheat. We took the cover off the case and turned a box fan on it to cool it. It worked fine the rest of the day. I found a replacement fan and installed it - same as original except the original moves 42cfm and the replacement 40cfm. We played one song and now the protect light comes on. We cooled it with the box fan again, no luck. Any ideas??

[Jazz P Bass]

It's broken?
Transistors as a rule do not like to be stressed by way too much heat.
They tend to fail.
The amp should be taken in to a good tech.
Really, it could be anything.