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Air running to FB and TF when FB in use

S

slash007

Well-known member
I noticed lately that when someone is using the FB in a bay, air is leaking and causing bubbles and foam to run out of the FB and TF to all the other bays. I can't figure out what would cause something like that, but assume it's simple. Any suggestions?
 
Sounds like the plunger assemblies in the solenoid bank either need cleaned or replaced, possible weak solenoids themselves.
 
That was my conclusion, so I checked a few of the plungers and they seemed fine. Didn't replace any solenoids. I can't think of any other cause, but seems odd for all solenoids to get weak for TF and FB for all bays.
 
It sounds like you've got a freeze protection check valve stuck open. Is it happening only when a certain bay is used?

It won't be a problem with the individual solenoids for the bays since there's likely not a common air solenoid to all the other air solenoids.
 
To test CB80's and Meps suggestion, take the air outputs off the air solenoid manifolds to see which way air is flowing...Bingo...
 
MEP001 said:
It sounds like you've got a freeze protection check valve stuck open. Is it happening only when a certain bay is used?

It won't be a problem with the individual solenoids for the bays since there's likely not a common air solenoid to all the other air solenoids.
Click to expand...

It is a lot worse in one bay, but I see bubbles coming out of TF and FB in all bays. That happens no matter which bay the FB is being used in. A weep solenoid check valve sounds like a possible culprit, but if it's happening in all bays, how is the air crossing over to the weep lines?
 
slash007 said:
It is a lot worse in one bay, but I see bubbles coming out of TF and FB in all bays. That happens no matter which bay the FB is being used in. A weep solenoid check valve sounds like a possible culprit, but if it's happening in all bays, how is the air crossing over to the weep lines?
Click to expand...

Do you have weep on your fb and tf? It might be a completely separate system from your normal hp weep.

If so just bypass it.... I have had this problem before. But the odds of more than one bay is odd.... unless it is old equipment that has been sitting? Or no chemical filter in the dilution tank maybe?
 
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Have you checked coil voltage on all air solenoids before and after activating FB in a single bay? Per CB80's suggestion: If the Air Solenoid Commons are daisy chained, have you checked each connection for continuity back to the control panel? These two checks should eliminate the electrical side of the equation.
 
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I checked the voltages on the solenoids and they were zero if not activated. Also took off the airlines from the back and nothing was coming out unless that bay was activated. There is white foam coming out of both the brushes and TF guns, so it is not just air that is passing through. Same for all bays. I replaced my weep solenoid for the Brush and TF as it was having issues, but that wasn't it. What else can I check? Here is a pic.

View attachment 955
 
cwguy.com said:
It could be a check valve for the low pressure weep.
Click to expand...


Based on my setup, I've thought about it and that has to be it. I'm sure that when FB is activated in the problem bay, it's running past the weep cv and into the weep manifold for all the FB and TF weep valves, then coming out of each one. I will check that out and confirm. Thanks!
 
To update, I finally made it into the attic. I only checked 2 bays, but out of 8 check valves, 6 were bad. All four weep check valves (TF and FB) and 2 out of the 4 that went to the chemical lines. What could cause that many failures? I am just going to buy 20 and replace them all.
 
I just spent time replacing all 20 check valves that went to the product and week for the TF and FB, and I still have the same problem! When the brush is being used, foam+air is coming out of the check valve. I made sure that it was installed the correct direction, and it is the fluid controls check valve that I have used many times with no issues. Also when the weep is on, water is running out of the chemical line check valve. I was shocked to start with that all of the original check valves would have failed, but figured they were old. What are the odds I received 20 brand new check valves that don't work? I don't believe that the check valves are bad (old or new ones) so something else has to be the issue. Problem is, I have no idea what the heck else it could be. A check valve is a simple device and shouldn't allow product or air to pass through the wrong way. Any suggestions/tips? I gave up for now until I can think of something else to try. Worst part is that the water is going into my air lines, so my regulators are going bad right and left because of all the water.
 
MEP001 said:
Can you draw a diagram of how your system works and post it?
Click to expand...

Sure. Just in the trough, or all the way? In the trough, air and chemical tee in together and share a check valve. They then attach to another t that has the weep attached to it via a check valve. Here is a picture:View attachment 963

The green lines are air. The blue lines are product and the yellow lines are weep. If I remove the yellow weep line and use brush, nothing should come out of the check valve, but it does. Same the other way around. If the product and air lines are removed and the weep is on, nothing should come out of the product/air check valve, but it does. This picture is of the old check valves. The gold has now been replaced with the stainless fluid control check valves.
 
Could it be possible the street elbow's and push to connect fittings you're using are threaded too far into the CV and holding the valve open? Have you taken the CV's out and checked them with air pressure for flow directing and sealing? Are you absolutely sure you have them installed correctly and in the right direction? Could it be possible the arrow is stamped in the wrong direction...I test all CV's before installing them for flow direction and sealing....

Just some possibilities and things that come to mind...How on earth could 20 CV's be bad?!?!? Sure sounds like something is holding them open so they flow both directions. Bench testing should show you what the culprit is...
 
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Robert2181 said:
Did it only start to happen when the weeps started to weep?
Click to expand...

No, I noticed it a couple of months ago. All bays would have white foam coming out from the TF and FB when FB was used in any bay. Found out that the brush was running into the weep manifold, and since FB and TF weep are on the same manifold, that's why they both had the issue. I went into the attic and took the weep line off of the check valve for TF and FB for all 5 bays. Product was coming out of the weep check valve. Seemed craze that all would fail, but figured they were old and maybe they had failed a while back and I bought all new. Put them in today, same issue. To be fair, I only checked 4 of the 20 I put in, but they all had the issue.

2biz, I should have bench tested them, but never had before and never had any issues. I actually bought 24 cv's and used 2 at my other wash and they worked fine. Arrow is pointing the right direction and I looked inside and it's stamped the right way. With the weep line off, the entrance to the cv has nothing to put pressure and open it. I don't see how the nipple could be screwed in too far. Here is a picture of how it looks with the new cv.View attachment 964
 
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