New return pump running very HOT
 

Have just recently installed a new barracuda pump and I am finding it is running extremely hot. I can barely touch the pump it is so hot and I have had to turn off my heaters and my aquarium temp is 30 celcius! (I normally keep it at 26) Some of my SPS is starting to RTN. I have no MH lights, this temp is hotter than my house. My aquarium is 180 gallon w 45 gallon sump. I have the pump dialed back about 50%. Vertical head is about 4 feet, horizontal about 6 feet. The only thing I can think of is my inlet pipe is a little longer than I would like, but it is the only way I could get it to fit/work in the area I have. Would this extra length cause the overheating? or is there some other trouble shooting I can do. The inlet is about 2 feet long, but I had to run the pipe up and over and down into the water again, so I guess it has to draw from about 4 feet of pipe. I used 2" pipe to do this. I have ruled out the skimmer pump and powerheads as the culprits.
Any suggestions??

I'm not sure if such a large pump can be throttled back by %50? I would contact the manufacturer.

http://www.reeflopumps.com/

YEah, I have an email in to them, but I am not expecting a reply until monday. I thought maybe there might be some good advice here. I thought you could dial them back as much as you wanted. I can try opening it up some more and see if that helps. thanks

Are you dialing back the input or the output? You should only dial back the output.

Have the pump run full out and see what happens.

the output

I have a Barracuda with 8' vertical dialed back a little over half way and my pump is not hot at all. I was told that it could be used this way.

oops - double posted

Barracuda as well at about 50%. Warm but definitely not hot.

I would be unpluging the pump if its that hot. But the pump is not adding the heat. If it is THAT hot that you can not touch it, I would assume it's heating the sump air, which is heating the water. The motor is not in contact with the wate, so can not directly transfer heat.

But a motor that is that hot can be dangerous, and possibly catch fire.

The Reeflo pumps have a Thermal shutdown switch, so i wouldnt worry about it too much. I have a dart, and mine gets ... by the sounds of it, as hot as yours, or hotter, but has never shut off.

One thing i did was dissassemble the motor cover, and take it out side, and went after it with an aircompressor. There was a lot of .... crap in there, after that it ran much cooler. also if you leave the rear cover off, just watch for the fan, it runs a bit cooler, and quiter too.