[Gripenfelter]

Originally Posted by braid11

Before throttling down, my Hammerhead sees probably max 17' head. That would be 3600 GPH, and even at 20' of head that is 3000 GPH. No wonder it overflowed the first time I tried it. I am at about 900 GPH now, so throttled down to 25-30% of max.

I think I can't get past 900 GPH because the air will not purge fast enough. My drains are about 3-4" under.

I only have about 1.25 inches from the top of the overflow box (about normal water level when all is balanced), until it flows out of the tank onto the floor. So not much time to fill the box, and purge. Maybe that is part of the problem.

Also, I read that when the drains are too deep in the sump, it takes longer to purge.

You are 6" under, and at 80% of full throttle, you must be flowing way more than 1000GPH. I know the system is supposed to be good to 2000GPH, but i can't get close to that.

So you drilled a hole in the elbow inside overflow box. You mean in the 90 elbow? Is it submerged when it's running? Because otherwise would't it suck in air and break the siphon?

Tom

Yes the elbow is submerged. I'm going to shorten the pipes though.