[ldzielak]

Delphinus,
I have the Flow rated version of the 4MDQ with the fan, it runs almost as hot as you decrib with no fan on your, must be much quieter. They do have an over temp protection (on mine I know). So I would not be worried about the heat. But after all my learning about 90 elbows and stuff on my overflows, I would not be suprised if you are starving the input. I have a 2" bulkhead, then 2" 90, then goes down to 1" line for 12" and then the 1" ball valve and union on the inlet. I have contemplated re-doing mine to give more smooth flow. If your using a 1" bulk head, with screens, you have a problem.

Lee