Water Filtration System Layout - Air in Pipes

[Joe74]

Hi All, first post on this informative forum.

I've got a significant amount of air in our house pipes which eventually leads to our showers slowing to a trickle. After clearing the air, the showers run for another week before slowing to a trickle. Have been trying to solve this mystery for 6 months and spent a significant amount on trial and error including calling in professionals. We are on a well, and have an iron filter, carbon filter and finally a water softener before it goes into the house. The issue seems to come from the water filtration system as the water has no bubbles in it before the filtration system, but immediately after it has the color of milk before the bubbles dissipate.

I have by bypassed individual filters and the whole system, and while at first after running the water for a while, it seems to clear, but then after sitting for an hour or so, the issue returns with air in the water.

I've attached a photo of my layout. This system is wedged in a closet and there are reason why I had to install it the way it is. Yes it is a little back to front.

My question to those in the know, is it possible that the upward loops, two them, running from one filter outlet to another inlet is causing air to be trapped when the water settles in the filters, and when water starts flowing the air goes into the water stream causing the air in the water issues. Would the problem be solved if i had them all as downward loops.

Before i re-plumb the upward loops do you think that is the cause of the problem?

Any help/advise would be much appreciated.

 

[Reach4]

Air in the pipes would cause air to spew out of the showerhead -- not slow the flow of liquid water.

 

[Sponsor]

 

[Joe74]

Air in the pipes would cause air to spew out of the showerhead -- not slow the flow of liquid water.

It's very real, it's called an "air lock".

"An air lock is a restriction of, or complete stoppage of liquid flow caused by vapour trapped in a high point of a liquid-filled pipe system. The gas, being less dense than the liquid, rises to any high points. This phenomenon is known as vapor lock, or air lock".

 

[Reach4]

It's very real, it's called an "air lock".

"An air lock is a restriction of, or complete stoppage of liquid flow caused by vapour trapped in a high point of a liquid-filled pipe system. The gas, being less dense than the liquid, rises to any high points. This phenomenon is known as vapor lock, or air lock".

Not real in pressurized plumbing.

 

[Joe74]

Not real in pressurized plumbing.

What else could be the cause of both showers slowing to a trickle after a week of air/water spurting out. Water in nearby faucets flowing normally. I think it has something to do with air getting trapped in the thermostatic mixing valve and associated piping. When i pull the thermostatic valve from the fixture, there is a few minutes of gurgling, re-insert the thermostatic valve, re-assemble fixture and then we're good for another week.

 

[Bannerman]

There is a fitting that is partially obscured by the hanging garden hose. Remove the hose and retake the photo to show the fitting located between the iron filter and the contact tank at the right side of the photo.

Perhaps the backwashing iron filter utilizes a pocket of air to oxidize ferrous iron and the fitting that is obscured maybe an automatic air eliminator valve which is not functioning properly?

 

[Joe74]

Without the garden hose in the way. I believe that’s just a pressure relief valve.

There is a fitting that is partially obscured by the hanging garden hose. Remove the hose and retake the photo to show the fitting located between the iron filter and the contact tank at the right side of the photo.

Perhaps the backwashing iron filter utilizes a pocket of air to oxidize ferrous iron and the fitting that is obscured maybe an automatic air eliminator valve which is not functioning properly?

With garden hose removed. I believe it's just a pressure relief valve.

 

[Bannerman]

I suspect it is an air elimination valve which may be similar to the now obsolete Sparco HV180 automatic air vent. https://www.statesupply.com/sa1090

A Honeywell EA122A1002 might be a better alternative. https://www.ebay.com/itm/HONEYWELL-...d-water-1-8-Inch-MPT-EA122A1002-/160932134364

 

[Reach4]

That may be an air admittance valve to prevent a vacuum from forming. If you would like to see some discussion of that, let me know and I will try to find the thread.

I would like to have a pressure gauge at some intermediate point. When you take a shower, make a movie of the pressure gauge. If you get the bad flow, check the movie of the pressure gauge to see if the problem is before or after the gauge.

Where is the pressure switch? There should be a gauge there already. Start with that gauge, in case the pump has a delayed start at times.

 

[Joe74]

That may be an air admittance valve to prevent a vacuum from forming. If you would like to see some discussion of that, let me know and I will try to find the thread.

I would like to have a pressure gauge at some intermediate point. When you take a shower, make a movie of the pressure gauge. If you get the bad flow, check the movie of the pressure gauge to see if the problem is before or after the gauge.

Where is the pressure switch? There should be a gauge there already. Start with that gauge, in case the pump has a delayed start at times.

Yes it’s a vacuum breaker, specified by manufacturer of the contact tank to be installed.

The pressure gauge is at the pressure tank. I will check during shower. But I’m certain it’s not a water pressure issue. The bath tap in same bathroom has plenty pressure while taking a shower. I think it’s the type of shower fitting or piping configuration in the showers that causes the problem with the showers as a result of all the air in the lines.

 

[Reach4]

The pressure gauge is at the pressure tank. I will check during shower. But I’m certain it’s not a water pressure issue. The bath tap in same bathroom has plenty pressure while taking a shower. I think it’s the type of shower fitting or piping configuration in the showers that causes the problem with the showers as a result of all the air in the lines.

That is new info. If the shower shows very reduced flow while the lavatory does not, then the problem could not be anything in your photo. On the other hand, if not while, then the lavatory use might be a lower flow for less time, so the problem could be in your picture or before. But I think you are saying DURING the problematic shower.

So in that case, I would wonder if the showers have a pressure balancing valve. And only the hot or cold has a problem. That could be the case if the cold bypassed the softener. A few people do that. I would think you would not be one of them, since your water warrants a really fancy treatment system.

 

[Bannerman]

I have by bypassed individual filters and the whole system, and while at first after running the water for a while, it seems to clear, but then after sitting for an hour or so, the issue returns with air in the water.

Not clear on whether the air problem returns while the system continues to be bypassed, or when sitting for 1-hr while the system is not bypassed.

Your earlier comments seem to suggest the air problem is only occurring on a weekly basis. Since an iron removal system will usually require backwashing every few days, that suggests the iron system is not the likely source of a weekly air problem.

Because a metered water softener will be more likely to regenerate on a weekly basis, this leads to suspicion the air-check valve at the bottom of the water softener brine tank may not be closing as designed which is allowing air to be drawn into the softener after the brine has been drawn out from the brine tank.

The WS Brine Draw cycle is usually programmed for 60-minutes duration, but the brine will typically be transferred from the brine tank within approx. 15-minutes whereby the remaining ~45 minutes will function as Slow Rinse to continue to push the transferred brine through the resin tank and out to drain while also rinsing brine from the resin. Once the level of brine in the brine tank has dropped sufficiently, the air-check valve at the bottom should be closing to prevent air from being drawn in during the remaining Slow Rinse cycle.

Suggest performing a manual regeneration of the softener at a time you can be present to observe the cycle.

The first phase of regeneration is usually Backwash for typically 10-minutes or less.

The 2nd phase is usually Brine Draw. The brine level within the tank should become lower over the following ~15-minutes until little brine is remaining and the level does not lower further. At that point, no air should be heard being drawn from the brine pickup assembly within the brine tank. If air is being drawn, then there is an issue with the air-check valve which will need to be corrected.

If your shower valve is a temperature balancing control version such as Moen Posi-Temp, a lack of water in either the hot or cold inlet to the valve such as resulting from air in either line, may prevent almost all flow to the shower head/spout. As Reach4 suggested, a similar situation can also occur with pressure balancing shower/bath controls.