Need help with RO solenoid shut-off

[Delphinus]

I have rearranged my topup for my tanks into a single reservoid auto-fed by the RO unit. Problem is the reservoir is now 30 feet "downstream" of the RO unit (I used 1/4" line) and now the shut-off doesn't seem to shut the RO unit off when the reservoir is filled.

It works fine when the output line is about 6'-8' or so. So I'm guessing that what's happening is the pressure takes a LOT longer to buildup in a 30' section of line over a 8' section of line (the solenoid works off pressure .. the pressure builds in the output line once the float valve is shut, the pressure moves the solenoid and shuts off the intake to the RO.)

So here's the question. Does my theory seem reasonable? (I had contemplated using 3/8" line instead of 1/4" because I was worried the line was too long, but if my theory is correct, the 1/4" is still better because the 3/8" line will take even longer to build up enough pressure to shut off the RO).

[StirCrazy]

Tony can you move the RO closer to the reservoir? it might be that because of the lenght the signal to shut it down is to weak to actually stop the supply. I am assuming you are using a pressure shut off here in conjunction with a float valve. If not let me know what you are using.

Steve

[Delphinus]

That is what I'm using. Unfortunately moving the unit itself isn't really an appealing option because where it is, is convenient for having the unit close to a source and close to a drain. I'd have to run two lines instead of one.

I adjusted my float valve so it shuts off at a lower level, it just seems to require a little more time for the pressure to build up sufficiently. I gave it a shot last night and it seems to be working. Gonna watch it for a day or two before I really decide if it's working.

[ldzielak]

Tony,

Water is not compressible and the pressure should be same no mater how long you lines are. I can't imagine you have enough air in the RO water to cause any spring effect that would cause a long delay. If the pressure is not high enough to shut off the solenoid, then you have a leak. The 1/4" line could also be flexing, but I have always had long lines, first installation was 20 feet, now I have 40 feet. No problems.

Lee

[Delphinus]

Yeah, water isn't compressible but I'm pretty sure that given enough pressure, pex can bulge a little bit (kind of like a really long thin water balloon), so I was thinking that maybe the pex line was doing some of that. More line == more surface area .. etc. etc. blah blah blah. (I work for a pipeline automation company remember? :razz: Oh right, you Metso guys sold us off, we were making too much money or something and it was making the rest of the company look bad. J/K!! :lol: :wink: :biggrin: )

Anyways the shutoff part works fine now (there is a lag though between float valve shutoff and solenoid shutoff) but now the really annoying thing is that the solenoid reopens about every 5 minutes for about 30 seconds or so and every time it happens it sounds like someone having really bad gas ("EeeeeeEEEEEyyyuurrrrrrRRRRp!!!!!!" That wasn't me, that was my RO unit. Honest! :redface: ) .... and you can hear it throughout the entire house. I've tried adjusting the throttle a bit but it doesn't really change anything except for the frequency.

I don't know... I have about 30-40' of 1/4" pex and maybe that is an inappropriate tubing to use for this application? Should I think about stepping it up to 3/8" or something? I don't really see how the increased diameter would really help with this phenomenon, though, now I'm starting to run out of ideas.

For now I just turn the unit off if it gets too annoying, which seems to work OK so long as I remember to eventually turn it back on (the reservoir servicing two tanks is only 20g, but the powerhead pressuring the tank lines sits about halfways up the reservoir (I hope to eventually make this a sort of kalk reservoir) and it doesn't take more than a day and a half or so to replace 10-15g of evap from the two tanks).

[ldzielak]

So sad to hear you miss Metso!!! I'm prety sure my little division will be up next for sale net, since we are also have a new idea about making money, not spending it uselessly, but don't get me started....;)

I can't see how making the line bigger would make the problem better, I would think it would just get worse. I can't hear mine at all. Maybe you solenoid needs a cleaning? Just a guess.

You could also install a secondary solenoid, electric on a timer, so it is only on for 1 hour a day, or enough time to make noise and fill your container.

Lee

[StirCrazy]

Actualy making the line 3/8th or 1/2" might do the trick.. the way thoes work the back pressure from the output sends a signal back to the unit which uses that pressure to pinch off the supply. so if you have a very long tube you will have compressability from the air in your water. also there is some give in plastic lines and when you are talking about a long run this adds up.. so what you have happening is the unit shuts the water off then as the water settles and compresses and the pex releaxes the pressure drops which allows your valve to flutter..

I still say the best way to stop it is to move your RO closer to the float valve. Also when yuo use a float valve it is going to flutter a bit as they are slow opening and not "ON" or "OFF" like.

Steve

[Delphinus]

Well ... maybe my next house I can have the tank area closer to the water source & drain.

Maybe I'll try the larger tubing for now if I feel really ambitious.

Frankly I'm a little disturbed just how much water is flowing into my tanks. The evaporation rate is insane. If it would be a little slower then at least it would be a little better.

You could also install a secondary solenoid, electric on a timer, so it is only on for 1 hour a day, or enough time to make noise and fill your container.


Hey don't laugh I have been considering that. Just a garden hose type valve, they're not that expensive and I can just set the unit to be on when I'm not home.

Good luck with your spinoff/selloff thing. Hopefully you can at least end up at a company whose name people can actually spell, or at least not have an embarrassingly long email address. When I tell people the "@telvent.abengoa.com" domain they're like ... "A Ben .. what?" .. Yeah. Great, laugh it up (I really like how all the email headers are in Spanish. When people send me email and it bounces the message is like .."Los Sientos, no routo del hosto. Server siesta... Hasta Manana!!!")

[Canadian Man]

Good luck with your spinoff/selloff thing. Hopefully you can at least end up at a company whose name people can actually spell, or at least not have an embarrassingly long email address. When I tell people the "@telvent.abengoa.com" domain they're like ... "A Ben .. what?" .. Yeah. Great, laugh it up (I really like how all the email headers are in Spanish. When people send me email and it bounces the message is like .."Los Sientos, no routo del hosto. Server siesta... Hasta Manana!!!")

You make me laugh Tony! :lol:

[Buccaneer]

When people send me email and it bounces the message is like .."Los Sientos, no routo del hosto. Server siesta... Hasta Manana!!!")

I will have to ask my Mexican friend to translate that for me

LOL ... you need to quit that job and go on the comedian circuit :biggrin:

Think of all the reef shops you could visit on the road and send us back some really cool frags :eek:


Cheers

[EmilyB]

but now the really annoying thing is that the solenoid reopens about every 5 minutes for about 30 seconds or so and every time it happens it sounds like someone having really bad gas ("EeeeeeEEEEEyyyuurrrrrrRRRRp!!!!!!" That wasn't me, that was my RO unit. Honest! :redface: ) .... and you can hear it throughout the entire house.

I agree. Tony has hilarious ESCAPADES. I really can't wait to get the "anemone spawning" smell description from Linda directly tho..... :lol: :mrgreen:

[TANGOMAN]

Tony, I've just installed an RO/DI unit in the basement and I'm running 1/4" lines to two reservoirs upstairs in addition to the one in the basement. I'm not sure of the total combined length but it's gotta' be close to 75 feet. Sticky valve sounds like a good possibility ? So too does air in the lines...?
You can always say it was the cat...

[Delphinus]

No noise? How often does it reopen to allow more water through? I can live with the noise, I'm just really surprised that I seem to get 20-30 seconds of flow every couple of minutes. No leaks, none than I can find anyways. I knew I had a lot of evaporation out of my tanks, but could it really be that much?

But like other tank-related noises, I'm starting to tune it out, so it's not really a big deal anymore (unless it's indicative of something wrong that needs attention).

What did you use for tubing, BTW. Pex? Or something else?

[TANGOMAN]

There is a "fluttering" noise, very faint though. My set-up is not continuously open though. I run lines up to reservoirs behind the tanks contolled by a float valve. That reservoir then gravity feeds to the sump through another float valve. None of the reservoirs are "pressure fed" unless I open the inlet valve to the RO unit. I still want to do that "garden hose timer thing" as sometimes I leave the inlet valve open and that has potential for bad things to happen...not that they ever happen to me. :rolleyes:
I hear the noise only when I'm beside the unit and it has been "shut-off" for a few minutes. Balancing pressure through slow leakage was my assumption...?
But we too have cats so maybe it was him ? There is usually another sense that is stimulated shortly after hearing that sound...much like your cat demonstrated to me :eek:
With the relentless heat of the past few weeks and the fans goin' full tilt to keep 'em cool, I'm evaporating like crazy too !
Tubing ? Aaaah...flexible copper (Cu) of course ! Whaddaya think I'm stupid. (Don't answer that...). I'm not certain what it's called :redface: , I'll assume it is. I thought pex was grey and not available any smaller than 1/2" dia. Mine is "cloudy white" 1/4" flexible. I am of course still refering to the tubing... :rofl: MAO...

[Delphinus]

The grey stuff that I think you're referring to is "poly-B" which isn't available anymore because of its tendency to break down when carrying hot water, and, as the story goes, is apparently a big problem for those heated basement floors that used polyB and after a class action suit or two the stuff was pulled off the market altogether. Pex is the replacement, it's kind of smoky white opaque. It is available in 1/4", it's just the standard stuff for ice makers, furnace humidifiers, etc.

I have no idea what the coloured tubing is that I see everyone else has (whenever I look at pictures of calcium reactors or whatever), I've never been able to find any of that (not that I've looked really hard ... I know that Rona, HD, and Distiller Depot doesn't have it).

What does a "fluttering sound" sound like. I am trying to imagine this sound but for the life of me I can't imagine ever describing the sound mine makes as a fluttering. More of a groan or a borborygmi (*)

The function is fine, it's just that the noise is a slight nuisance. I wish I knew what I could do to make it go away. Short of putting yet another timer-controlled valve on the whole thing, which is do-able, but a little rediculous (as in "where does this all end" which is a question to be asked while waving your hands in the air and rolling your eyes, just immediately prior to tearing up some more $100 bills and banging one's head into a brick wall and turning on a garden hose and watering your basement carpet. But I digress..)

My RO unit empties into a reservoir behind the tanks. Although it's a solid 20g in volume, the reservoir will empty in 24 hours if I leave the RO off for that long. From the reservoir I have a line which T's off and each end goes into each tank.

Where did you get your shutoff valve from, or more accurately I should ask, who made your valve. Mine is just the one you can get by Kent.

--
* How's that for a big word? From Dictionary.com:

bor·bo·ryg·mus n. pl. bor·bo·ryg·mi: A rumbling noise produced by the movement of gas through the intestines.

[TANGOMAN]

I'll try and answer the first question first... :confused: . The "fluttering sound" sounds like, well, fluttering. I dunno' ? Unfortunately I lack your ability to put sounds into a written form. If ya' put your tongue on the roof of your mouth and exhale allowing your tongue to flutter it makes a fluttering sound... How's that ? A Rattlesnake with a hair lip ? :confused:
You described the tubing I'm using though your color description is far superior to mine. It's the humidifier stuff. The valve controlling the inlet is a 1/4" ball valve, brass. Threaded, with adaptors, and soldered to a 1/2" house line. I got it from Hose Headquarters.
20g in a day ? Wholly crap !!! I'm evaping' a gallon a day...
I got a variety of the colored tubing with this RO unit. It looks impressive but probably serves the same purpose.
Us bald guys must refrain from banging our heads against brick walls as there is little protection up there and the scars just don't look cool on the skull... :biggrin:

[Delphinus]

It's a ball valve? Ok, this sounds different. I beleive mine is a tiny gate valve. Hard to say, it just looks like a plastic white box with three hose threadings, one for in, one for out, and one to T off to the output line of the RO.

It seems to be working fine, other than it's a little disturbing that at any given moment I'm more likely to find my RO unit going rather than idle. It's basically like it's on all the time, flowing directly into the tanks, just throttled back ever so slightly to match the evap rate. Yeah ... well ... hmm I didn't notice the math before but I guess ... 20gallons of evap per day and a 24 gpd RO unit .... kind of adds up doesn't it.

Maybe there's part of the solution .. buy a bigger RO unit, thus the fill cycles would be much faster maybe? And a ball valve shutoff instead of a gate valve shutoff. I will have to visit this fabled Hose Headquarters you speak of.

[TANGOMAN]

Ya, the volume required will have that unit cycling frequently. I went for a 75 gpd unit but "future business plans" will reqire higher volumes.
This unit came with a needle valve that can be fastened to an existing water line and pierces it. I like "make work" projects so I did some cutting and soldering... :confused:
Regardless of the valve controlling flow into the RO unit it shouldn't be howling I wouldn't think. My experience in Construction Equipment hydraulics leads me to think that the pressurized water is howling as it passes through an orifice. I dunno', perhaps the inlet valve is "starving" the unit of required water. That would be more like a "cavitation" scenario. I suspect the problem might be downstream...?
Any luck trying to determine the whereabouts of the noise ?

[Delphinus]

In retrospect, I don't have 20 gpd of evaporation, it's more like 10gpd peak, and I'm not sure if I have a 50gpd membrance or a 24 gpd membrane. But still I guess that's almost 50% or 25% (depending on membrane) of capacity so I guess it still works as an explanation. Even on for 25% of the time makes sense, that you'd hear the unit going pretty often. Just a real eye-opener on the amount of evaporation this really is, I suppose.

I also maybe lied a little about all the downstream tubing being pex. I have the line T-d off to a 30g rubbermaid so I can have 30g of RO available at any given moment. The tubing that services this bucket is a sort of soft vinyl. It can handle the pressure OK (it used to be an indoor plant watering thing) but the hose is .. how would one describe it ... kind of soft and supple? So maybe it's stretching a bit which causes weird things to happen with the backpressure which in turn makes the solenoid weird? Maybe I should try replacing all my line with pex. I'm just out of pex at the moment.

[TANGOMAN]

It sounds like your set up similarily to me. I've got a "bank" of needle valves contoling flow to the tanks upstairs, open flow to a reservoir in the basement "laboratory". Can you block flow to certain "circuits" and do the process of elimination thing...?
That vinyl tubing may be the culprit. I kinda' think it may be in the RO unit though these things are relatively new to me :confused: .
I was goona' invite myself over for a look, and a beer, 'cause I was down that way to get stuff at Home Depot but Margo kinda' rolled her eyes so I passed. Now that would have been a night from hell for the guy in the plumbing department if two fish geeks showed up askin' questions that defy all the ethics of plumbing... :lol:

[Delphinus]

LOL -- you should have seen the plumbing guy when Wayner and & showed up at HD a few months ago to get his float valve going. We needed like 20'-30' of tubing and the guy was like ".. and now you need a saddle valve." -"No, we don't, but thanks." "No really," he insisted, "you have to have a saddle valve to hook this up to." "No thanks." "But you have to have a saddle valve!" "No, we DON'T!" "Yes you do!" This kind of went back and forth like this a few times until finally Wayne sort of piped in "We're COVERED. Thank you..." :lol: