Thanks!! I opened the return to max and shut down the siphon. It wouldn't even build up to the emergency. Opened up the siphon a little and worked from there.
It's much quieter now. However, I still heard noise coming from the 90 elbow. Sucks..
I might have a possible air leak? I had to shorten the pipe distance in the sump so I cut it and connected them with a PVC connector. I didn't use primer or glue, just pushed it in. It's just above water level in sump. Do you think that might suck in air?
I am not following you. You opened the return, ok. Then shut down the siphon? Why?
What size are your bulkheads?
Open the siphon valve all the way OPEN. Pull the air vent line off the open channel. (hang on to it, as you will need to reinstall it, after you get the system working right.) If there is a valve on the open channel, open that valve all the way—then remove the handle on it, and never touch it again. If you have any horizontal sections in the drain lines, those need to be angled down to at least 45°. Measure first, then cut off the pipes in the sump at 7/8" below water level. Don't guess: measure, mark, and cut.
If they are already shorter than that, don't bother with it.
Remove the added elbow down at the sump. If that pipe comes up too short because of that, you will have to replace that pipe, so it will not be too short. (eventually.)
Fire up the system, with the return line wide open. IF the top end of the system is built right, there is no way the tank will overflow with the return wide open. If the water level in the overflow does not rise, flow in the dry emergency for a while, then suddenly drop, with the settings as I have instructed, then you need to look at your return plumbing/pump and figure out why you got zip for flow.
AND/OR:
If you have 1.5" bulkheads, I would suggest you bush them down to 1", then back up to 1.5". There have been scattered incidents of starting issues with very low flow systems with large bulkheads.
After the startup sequence (a few minutes,) if there are bubbles coming from the siphon line, it is either air locked, (not purging the air) or there is an air leak. IF there are bubbles coming from the open channel, the water level is too high, and too much water is flowing in the open channel.
When the system is operating right, water level rises, flows in the dry emergency (and open channel) for a while (minutes.) When the siphon kicks in, the water level drops. With the valve on the siphon, raise the water level in the overflow till water just starts to flow in the open channel. This level is around the lower half of the downturned elbow on the the open channel, where it joins the bulkhead. Running water level is usually ~ the top of the downturned elbows.
Mrramsey: Your systems has the same basic issue that m0nkie's system has. You need to go through it a piece at a time, as indicated above. Increasing the size of the air vent will have the opposite effect than what you want. Increasing the size, means more air and consequently less water allowed, without bubbles. The folks that advise on quieting dursos have the physics reversed. It is not about letting more air in, it is about reducing the amount of water, for the amount of air you have. The balance is the point where water flows on the walls of the pipe, with calm air (not moving) in the middle.
NOTE: If the air vent line inlet is below the inlet to the dry emergency, too much water will flow in the open channel; the main siphon will not start, because the open channel will take too much flow...(yes that is circular) that is why I say take it off to get the system running right, and for testing the first level failsafe, the dry emergency, which should take water first, before the open channel, in the event of a siphon blockage. The only time the open channel should trip to siphon is if BOTH the siphon and dry emergency are blocked...
When you put the air vent line back on, if the system starts acting up, well...you know what the problem is...
