PVC Backflow preventor

TRIX · #1 12-06-2006, 04:09 PM

Hey. I would like to keep my return line below the water line. Is there any backflow preventors that I can use on the return line. My return line comes in at the middle of the tank on the bottom. I was hopping to do a spray bar along the bottom. But because this line won't go to the top of the tank if I loose power all the water would be sucked out of the tank and cause a major flood. Any suggestions. Thnx

muck · #2 12-06-2006, 04:16 PM

I wouldn't recommend doing it that way but if you insist on it make sure you install a check valve on that line. (Try to find a True Union one so you can take it out to clean periodically.) Of course you would also need a ball valve above the check valve so you can close the line off when you take the check valve out to clean.

hawk · #3 12-06-2006, 04:29 PM

You could drill hole(s) just below the waterline. This should stop the syphon when the water drops to the level of the holes. Keep the holes clean.

TRIX · #4 12-06-2006, 04:58 PM

Quote:

Originally Posted by hawk

You could drill hole(s) just below the waterline. This should stop the syphon when the water drops to the level of the holes. Keep the holes clean.

The entire baffel would be at the very bottom of the tank.

TRIX · #5 12-06-2006, 05:00 PM

Quote:

Originally Posted by muck

I wouldn't recommend doing it that way but if you insist on it make sure you install a check valve on that line. (Try to find a True Union one so you can take it out to clean periodically.) Of course you would also need a ball valve above the check valve so you can close the line off when you take the check valve out to clean.

That's what I figured. A long term pain in the butt. Do you have any other suggestion.Should I scrap the baffel idea and just have my returns at the surface.

danny zubot · #6 12-06-2006, 07:12 PM

If you "T" the intake pipe going into the tank wall, and run a pipe straight up the outside back of the tank so that it is above the water line, it should break the siphon when the pump is off. You need to make sure there is no back pressure from your spray bar or this pipe will be overwhelmed, and flood.

muck · #7 12-06-2006, 07:25 PM

Better re-think that advice Danny.

Sure its no longer a syphon but the water is still going to backflow into his sump.

muck · #8 12-06-2006, 07:28 PM

I would run the return over the back of the tank or up through your overflow box and have the return near the top.

If you want to run the baffle system still put it on a closed loop. No worries about backflow and syphoning then. Only downside is you need another pump.

danny zubot · #9 12-06-2006, 07:34 PM

After reading the post again, I realized that missed this part.

Quote:

My return line comes in at the middle of the tank on the bottom.

In that case, please don't take my advise.

TRIX · #10 12-06-2006, 07:34 PM

Quote:

Originally Posted by danny zubot

If you "T" the intake pipe going into the tank wall, and run a pipe straight up the outside back of the tank so that it is above the water line, it should break the siphon when the pump is off. You need to make sure there is no back pressure from your spray bar or this pipe will be overwhelmed, and flood.

The return goes into the tank dead center on the bottom for 4 sides of viewing. Would this still work