$15 PVC Overflow

no the ph will not pull air it will stall and make a horrible noise. The hole for the vent should be in the highest spot. you could put a 45 then a 90 then another 45 this would make the high spot at the tip of the 90 causing air to gather there. this woud replace the 90 the d pipe and the next 90.

Richard
 
Just rebuilt the whole thing using 1 1/2 inch and 2 inch pvc. Now I'm having dificulty getting the syphon started. Any suggestions????
 
tubes d and k and the 90s on either side can be removed and replaced with a 45 90 45. this will put the 90 on top at an angel, then put the vent in the top of the elbow.
 
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This is a bad drawing but it should make the point.
 
moeandicy said:
Just rebuilt the whole thing using 1 1/2 inch and 2 inch pvc. Now I'm having dificulty getting the syphon started. Any suggestions????

If you have a valve on the output before the tee you can close it and the siphon should be easier to start. Or start yoiur siphon with a wet/dry vac. that is how I start my 1 hp koi pond pump if I lose the siphon(bad plumbing design).
 
IT WORKS!!!! The problem was that when I moved up to the 1.5 inch pipe I didn't take into consideration the increased size of the elbows and fittings. The cross was above D and K. Had to redo that. It was a PITA to get started but now it works awesome! Don't know how much flow I'm getting but I'm running the quietone 5000 wide open with no problems. Simulated power outage worked fine also. Next project will be a bigger sump. Thanks everybody for all the suggestions.
 
moeandicy;

Glad to hear you got it working!!!!

Mine is still running fine after 2 weeks... I put a LR with GSP's on my tubes hoping it will spread.

THANKS AGAIN tboned

Rockker
 
How far down in the tank should the tube that sucks the water in be and do you have to constantly moniter the water level or can you put the overflow far down in your tank so it has no chance of having the siphon broke. I don't want to have to worry about that.
 
I think that I am going to show everyone how a siphon works, but for the time being, fishonadic, your siphon will work but there is going to be a large drawback with it.

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If you look at the levels of A and E. In event of a power outtage, water will continue to flow until: A) the water level in the tank becomes lower than point A, B) until the water level in the tank becomes lower than point E.

A siphon works on a pressure basis and due to the fact that water is an incompressible fluid. For example a simple siphon that you'd use to change water in your tank. You stick a hose in, suck on one end, and the water comes out of the tank. Experiment with this. If you raise the level of the hose on the outside of the tank to the water level in the tank, the siphon will stop, but not break. It stops because the pressure at the surface of the water in the tank is the same as that at the end of the hose on the outside...atmosperic. When you lower the hose below the water level, the weight of the water that is below the level of the tank will create a "vacuum" that pulls water out of the tank. That is the same priciple that this overflow uses and all other overflow boxes use. I will draw it up later when I am done with my Home Work. Until then, your educations can wait until I have gotten mine. :smokin:
 
You didn't mention what the drawback is did you? It looks good to me. The siphon goes until it drops beow A or E, and then stops. It would start again if the water level raised again, right?
 
Steel_Phoenix: pvtschultz said that In event of a power outtage, water will continue to flow until: A) the water level in the tank becomes lower than point A, B) until the water level in the tank becomes lower than point E. If you look in my gallery I have fixed the problem, at least I think I have. By moving E up so it is equal to the water level.
 
If you want 900 GPH I would suggest going with bigger than 3/4 inch pvc. I would use at least 1.25 just to be on the safe side. I don't believe (from my experience in the last few days) that 3/4 inch will handle that much flow.
 
fishonadic said:
If you look in my gallery I have fixed the problem, at least I think I have. By moving E up so it is equal to the water level.

There is where the other problem lies. I need to look at the original plans more, but if you raise E up to the water level, you'll lose your siphon power and won't have as much flow. I am going to build one or more of these this weekend and "experiment" with it instead of doing what-ifs, but I know that there has been very positive remarks using this design so really experimentation is going to be the one way of finding out how well it works. One thing that you can do is just dry fit everything so that it is tight. It will be water resistant enough for you to be able to fire it up and see how it works. That way you can tear it apart if it dosn't work well and not waste so much. But then again it isn't that expensive so you aren't really waisting that much money.

EDIT: Okay, the inlet and the outlet should be the same height for this design. That way when the water stops flowing, the level in the tube inside the tank (don't remember the letter) will be lower than the other level and the siphon will stop, but won't break. When the pump starts back up, the siphon will begin again. I think that I design enhancement would be to increase the intake size to allow for air to escape before getting sucked into the siphon...Like I said before, experimentation.
 
The purpose of A is to provide Surface skimming. You can actually take the whole A assemble off and the water level will drop to E
As long and the down tube from the siphon is lower in the water to prevent air in the tubes. The A assembly allows you to raise the water level higher. Inside the tube it is acually down to same level of E. Water always seeks its own level. You are rught about losing the power of the siphon. There must be a reasonably long pipe on the outside to allow the outgoing water to form a partial vaccuum and pull water out of the tank.

Aquayne
Demovid@hotmail.com
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