RO waste outlet runs permanently

[PranK]

Hi All,

My 5 stage RO unit (and another 3 stage) seem to just constantly run water out of the waste line.

The RO unit(s) are about 30 feet from the tap and I use a float switch to disable them when the reservoir is full. This part works well with the reservoir always full but never over flowing.

I just don't think that the waste drain should be running all the time and given Australia's current drought status I'm keen to stop any water wastage.

Maybe I have lost too much pressure by being too far from the tap?

Thanks in advance.

Christian

 

[lapin]

If water is coming out the waste line you do not have the water stopped before the unit or it is sucking water out of your reservoir.

 

[Snoopy 67]

Does your unit have an Auto Shut Off Valve?
It's a mechanical unit that attaches to the water lines.

 

[mfinn]

I've had to replace my auto shut off valve because of this issue.

 

[JoshH]

Does your unit have an Auto Shut Off Valve?
It's a mechanical unit that attaches to the water lines.

This +1 you seem to be missing a key component and that is the auto shut off valve... this will cut the flow to your entire unit by blocking the product and waste line at the same time when your reservoir is full. Unless as mentioned above, you have one and it's faulty in which case you need a replacement..

 

[redfishbluefish]

Your Automatic Shut Off valve is either not hooked up correctly or is shot. It's that small boxy looking thing that has four tubes coming into it. Check that it's hooked up right, and if so, replace this valve.

 

[PranK]

Thanks for the replies guys!

I do have that valve on both units. I was thinking that the mains pressure was not high enough to actually cause the valve to function.

I'll grab a new one today and see what happens. I'll report back.

Thanks again.

 

[Eggs]

Thanks for the replies guys!

I do have that valve on both units. I was thinking that the mains pressure was not high enough to actually cause the valve to function.

I'll grab a new one today and see what happens. I'll report back.

Thanks again.

I had issues with using those auto-valve shutoffs working. I never did get them to function and came to the conclusion that incoming water pressure was a problem. However, it was high pressure.
My water source was right off the main line entering my house. I believe that pressure was too high for the auto-valve back pressure to overcome and shut the valve.
I didn’t measure anything, but knew I had high source water pressure and the needed auto-valve pressure from the opposite just couldn’t match it.
In hindsight I should have regulated the input water pressure.

Maybe check your pressures?

 

[UCF Alum]

Is you flush valve closed?

 

[Thaxxx]

Those videos show a pressurized tank that cause the valve to shut. Does it work the same with a float cut off in reservoir?

 

[redfishbluefish]

Those videos show a pressurized tank that cause the valve to shut. Does it work the same with a float cut off in reservoir?

Yes

 

[mfinn]

Those videos show a pressurized tank that cause the valve to shut. Does it work the same with a float cut off in reservoir?

I use a float valve on both my topoff and water change containers.

 

[PranK]

I had issues with using those auto-valve shutoffs working. I never did get them to function and came to the conclusion that incoming water pressure was a problem. However, it was high pressure.
My water source was right off the main line entering my house. I believe that pressure was too high for the auto-valve back pressure to overcome and shut the valve.
I didn’t measure anything, but knew I had high source water pressure and the needed auto-valve pressure from the opposite just couldn’t match it.
In hindsight I should have regulated the input water pressure.

Maybe check your pressures?

Yeah thanks for that. I might be on the opposite end of the scale, we don't have particularly high pressure here, perhaps because we're on quite a large hill. I'll see if I can get a gauge to see.

Is you flush valve closed?

Not sure what that is. If it is the float valve, its definitely shut as no water continues to run through it and it never overflows.

 

[Topekoms]

i had to replace the auto shut off and the RO membranes due to failure it fixed my issue for constant running

 

[ca1ore]

Not a great idea BTW, to use a mechanical float valve to keep the reservoir always full. Means your RODI is frequently dispensing small volumes which burns through the DI much faster. Plus those float valves aren’t particularly reliable.

 

[mfinn]

Not a great idea BTW, to use a mechanical float valve to keep the reservoir always full. Means your RODI is frequently dispensing small volumes which burns through the DI much faster. Plus those float valves aren’t particularly reliable.

I agree 100%.
I left my rodi on over night to fill my 55 gallon storage barrel and just saw this thread notification and went out to the garage to look at my barrel and it was completely full and overflowing.
I followed the water trail all the way across the garage and out the door. Since it rained last night and the ground was wet, I have no idea how long the water had been running across the floor.
Time for a new float switch.

 

[PranK]

What is a good alternative to a float valve?

Btw I changed my shut off valve and it made zero difference.

I have a tap before my float so I can completely disable the outlet. Turning this off doesn't stop waste water draining. I can definitely see a difference in volume when the float is open to when the outlet is closed.

The gauge on the ro unit reads roughly 45psi.

Thanks for the help but any other suggestions?

 

[PranK]

Perhaps I could use a combination of a tap timer and the float? Only make the mains water available for an hour a day or something...

 

[Topekoms]

What is a good alternative to a float valve?

Btw I changed my shut off valve and it made zero difference.

I have a tap before my float so I can completely disable the outlet. Turning this off doesn't stop waste water draining. I can definitely see a difference in volume when the float is open to when the outlet is closed.

The gauge on the ro unit reads roughly 45psi.

Thanks for the help but any other suggestions?

How old are the membranes?

 

[mfinn]

After looking closer at my float switch, the adjustment wing nut has loosened and allowed the float part to move higher which requires more pressure to make it close.
So after moving it to the correct position and tightening the wing nut and testing it 5-6 times, I'm staying with it.
It's about 8 years old.