Trouble restarting siphon

[jharding08]

The 1" standpipes may be creating some of the issue and there is more than likely an air leak with the press fitted cap.

Lastly, you can drill a few small 1/4" holes in the siphon standpipe just above the normal operating level of the sump. This will allow the air to be purged during startup.

Bean, thanks for chiming in. I'm loving how quiet the system is once I get the siphon going. How far under the sump water level do you terminate your siphon line? Does the open channel and emergency have to be at that depth as well? Do the drains need to be parallel to the water surface to get the siphon?

If you can see from my sump picture, using 45 elbows, I barely can barely get the drain pipes over to the sump section to get it vertical. I pretty much have the 45 elbow to get it vertical in the water. Is this affecting the siphon? Siphon line is the one in the back in the picture.

Couple Things

1: Make the Cap AIR TIGHT. Yes opening the Cap to purge the air is helping you. but you want the full siphon Line AIR TIGHT for it to start automatically

2: Larger Drain Pipes. 1.5"

3: The Drain should be JUST BARLEY under the water. Mine was 1" below the water line and the full siphon would take FOREVER to happen. cut a 1/2 off and now it starts within 20seconds.

4: Make sure the Air bubbles from the standby Drain are not flowing up into the full siphon drain. On my system I had to add a 45 degree elbow to direct the air bubbles away from the Full Siphon Line. were it enters the sump

NICE SUMP

Thanks for the compliment on the sump. I designed it myself and had my girlfriends dad build it for me. He only charged me for materials which is nice. If I could do it over again, I would make the fuge/LR chamber smaller and add more to the return chamber. With a C2C overflow, the return area needs to hold as much water as will go in the overflow before drains kick in

 

[4Hummer]

Was wondering about your Return Section, Mine is much larger and almost goes dry while the Overflow box is filling.

Good luck getting the siphon all figured out. Once you have it dialed in it works flawlessly. Took me some trial and error.

 

[jharding08]

Was wondering about your Return Section, Mine is much larger and almost goes dry while the Overflow box is filling.

Good luck getting the siphon all figured out. Once you have it dialed in it works flawlessly. Took me some trial and error.

I have to run my float switch pretty high, so that it is a full return section and even some of the fuge section of water to go into the return line. I'm sure I can figure something else out like another reservoir, but that works for right now.

 

[uncleof6]

Bean, thanks for chiming in. I'm loving how quiet the system is once I get the siphon going. How far under the sump water level do you terminate your siphon line? Does the open channel and emergency have to be at that depth as well? Do the drains need to be parallel to the water surface to get the siphon?

If you can see from my sump picture, using 45 elbows, I barely can barely get the drain pipes over to the sump section to get it vertical. I pretty much have the 45 elbow to get it vertical in the water. Is this affecting the siphon? Siphon line is the one in the back in the picture.

For future reference, you may wish to plan more carefully, so it is not such an extreme stretch to hit the proper section in the sump with all three pipes.

The 90s you had originally could very well affect the performance, but with the 45s, it should not...

I am pretty certain it is an air leak in the siphon causing the starting issue. Until you get the siphon line sealed up 100%, further troubleshooting is a waste of time. This system is very predictable, and there are no "mysterious" causes for start failures. Even though the holes bean mentioned will help, they should not be necessary, if the system is setup (sealed up, etc) properly.

 

[jharding08]

So I got a slip to threaded adapter and threaded the caps onto the open channel, siphon and emergency drain pipes.





I also cut the ends of the drains to be closer to the water level (siphon on right, open channel on left)


Upon closer inspection, it is the open channel that makes all the bubbles when starting back up. What happens is that the water level at the elbows in the overflow gets above the inlets and then more water gets forced into the open channel causing gurgling. The water level in the overflow will then drop and it will quiet, then it will rise and it will expel bubbles again. This goes on until the siphon starts. I still haven't been able to get it to start automatically. The siphon line looks like it has one bubble in the drain outlet that never really gets purged. I can see it growing and shrinking right at the outlet.

I know the siphon drain is sealed, why wont it expel the air? Not enough pressure at the top? I have tried to adjust the siphon ball valve so that the water level is right at the bottom of the down-turned elbow, just enough to have it not suck air. And I have also tried to raise the water level very high, so it is above the whole down=turned elbow, about midway up the emergency drain.

I am running a 768 gph pump currently with a 5' rise. is that not enough flow to get the siphon purged?

 

[4Hummer]

Are the Air Bubbles from the OPEN Channel Drain going up the Full Siphon Drain?

I had this problem at first and had to add a 90 degree elbow to the Open Channel and point it away from the Full Siphon

Hard to tell from the pics, but how far below the water line is the Full Siphon line? Less than 1/2"

Mine does the same thing your describing. TONS or water and air come gushing out the Open Channel on start up, but about 10-30 seconds later the Full siphon kicks in and hardly ANY water come out down the Open Channel (Just a trickle)

Try the Elbow. Betcha your having the same problem I did, with the Open Channel and Full Siphon lines so close together, Air from Open Channel goes up the Full Siphon Pipe, and never allows it to fully purge all the air

 

[jharding08]

Its about 1/2" right now. If I add a 90 to the open channel, that will make it more than 1/2", but it shouldnt matter with the open channel, right? Do angles at the water line cause issues with the siphon?

 

[4Hummer]

Its about 1/2" right now. If I add a 90 to the open channel, that will make it more than 1/2", but it shouldnt matter with the open channel, right? Do angles at the water line cause issues with the siphon?

Doesn't matter with the Open Channel. You don't have to glue it on either. Just stick it on and see

My Open channel drain line is about 3 inches below the water line. and it will still go full siphon in a emergancy

 

[4Hummer]

This is what I mean by the Drain lines being close together

Don't have a better pic, First line that enters the Sump (at the back) is my Full Siphon, Right beside it is the Open Channel. That is the pipe I had to ad the 90 elbow to, to direct the air bubbles away from the Full Siphon, Last is emergency line

You can barley see the 90 in the pic



If you need, I'll try and get a better pic tonight of the drain lines (And Elbow)

 

[jharding08]

This is what I mean by the Drain lines being close together

Don't have a better pic, First line that enters the Sump (at the back) is my Full Siphon, Right beside it is the Open Channel. That is the pipe I had to ad the 90 elbow to, to direct the air bubbles away from the Full Siphon, Last is emergency line

You can barley see the 90 in the pic



If you need, I'll try and get a better pic tonight of the drain lines (And Elbow)

Is that flex pvc? How does that work? I could probably use something like that to get all my lines into the drain area, since its such a tight turn

 

[4Hummer]

Yup Spa Flex. Just at the bottom on this tank tho. Works great! My Old 4ft tank used spa flex for the entire run. Just heat the pipe up a bit and you can easily mold and shape it. (bath tub full of REALLY hot water makes it really easy to bend)


This time I spent a little more time pre-planning the drain lines and hole placement

Here is a build pic when I first started doing the plumbing:

 

[jharding08]

I'm trying to think if I can move my sump more the right side so the drains and the sump drain area will match up more, but I have my Iwaki plumbed in on the right side of the sump and it takes up most of the room there.

 

[jharding08]

Looks like it was the air from the open channel that was causing the siphon not to start. I put a right angle on the open channel drain away from the siphon drain and the siphon started almost immediately with little to no large air bubbles in the open channel.

Problem is now that I cut the open channel drain too short when troubleshooting so there isnt enough 1" pvc left to attach the 90 elbow too. I had to hold it there to get the siphon to start. Guess I'll just create a new open channel drain piece from the union down. Gotta love unions!

Thanks for all your help in getting this resolved

 

[4Hummer]

Glad you found the Problem. I'm was 99% certain that was your issue. :bounce1:

Took me a little bit to figure it out myself. Was just sitting there one day watching the drain lines when I noticed all the air bubbles going up the full siphon line, and thought to myself. BETCHA that's the problem

 

[jharding08]

Quick question - after putting the right angle on the open channel in the sump to divert the initial air bubbles on startup, the siphon was working great. It would take some time and some noise, but would end up dead silent with the water level right at the bend in the 90s in the overflow

Currently I am seeing the siphon take a little longer to get the water level in the overflow to the bend. I am hearing water running through the drain line in the siphon and the water level is at the top of the 90 not the bend. In order to get the siphon drain silent again, I need to open up the siphon ball valve, let all the water flow through and then readjust to the right level. It is silent at this point.

Not a big deal in the grand scheme of things, except with a higher water level in the overflow, the sump is less, causing the ATO to fill it back up (every 30 min on a float switch.

Could it be detritus stuck in the drains? I have had a ton of diatoms and algae since my new sand bed. Once i open the siphon all the way and readjust, it quiets back down and I can set the level again.

Thanks for your help.