Ballvalve
General Engineering Contractor
My overflow tube puts out a ton of water and so far it seems to be a waste - inside the overflow.
Small hose in toilet tank - why?
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Ballvalve
Many old toilets overfill the bowl. That was mentioned in one of the earlier posts.
Especially if you have changed the original fill valve with a Fluidmaster 400A, you will see a lot of overfilling.
Also mentioned was Korky's MaxPerformance fill valve that allows for adjusting the bowl fill.
If you have a toilet that fills the bowl without the additional water down the overflow, then perfect. It would make sense to redirect the water then.
If the bowl is designed with refill in mind, then you have to look at that. A bowl this is too low before the flush, will not flush correctly. If the bowl is at the correct starting level, then you're good to go.
So many tanks, bowls and flappers. Not always have they been matched up correctly.
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Jadnashua
Retired Defense Industry Engineer xxx
This is one reason that Toto has a custom version of the Korky valve made for them...it keeps the balance of the bowl/tank correct so both refill at the same time. Some companies actually care about good performance which includes efficiency.
Ballvalve
General Engineering Contractor
I would say this has been a great thread, learning that many older toilets or those with new valves can save tons of water by testing the need for the tube in the overflow.
Why dont we have some more guys do that simple test and report back.
Why dont we have some more guys do that simple test and report back.
TheWind777
New Member
Well, I'm no engineer... and I don't think that had anything to do with this whole thread. That's just a chip some plumber had on their shoulder.
...
However, the engineer had a very valid question - which was never really answered properly.
Using 1970's toilet theories, there is absolutely no way that the bowl ever would have filled if you didn't have that little tube over the fill tube unless there were water leaking through the flapper valve because, by the theory - the water goes into that tube, through the holes that are under the rim and that is what fills the bowl.
That was a long time ago now.
Since then a gazillion different toilet tank designs were developed by a gazillion different manufacturers as Capitalism always has done; so there's absolutely no way to say the tube is needed or not needed for any particular toilet unless a person specifies the particular toilet design.
The facts are, he held the flapper ball down as it flushed, covered it with plastic, so by the theory - the only way that water could get into the bowl by conventional theories would be through the plastic tube - and if the plumbers had been correct by the generic theory - there is no way that water would go into his bowl - period.
But that didn't happen.
His bowl IS filling up and it is filling up to the correct level.
So, the ones who are being immoveable on the subject are the plumbers, not the engineer. The engineer is (still) confused as why his bowl is filling up to the proper level (as he should be).
After reading all these threads, I still have the question, "Why is his toilet bowl filling-up if the flapper ball is not leaking?"
The answer has to be that that particular toilet must have some advent to water entering the area where the holes are OTHER than through the plastic overflow tube; and that is what intrigues me. You can't get around the fact that water IS filling up in his bowl, PERIOD. And, apparently that water is not leaking through the flapper.
What?
I have found that people in professions oftentimes don't understand everything, themselves. They learn the 'right way' which is generally generic learning that sounds simple; but isn't always correct.
The first thing I would have asked is, "Who manufactured the particular toilet that you have?" There were a lot of posts, and maybe somoene did ask that; but it seems like it would be the first question I would have asked. I wouldn't, first, have jumped down the engineer's throat and then started making fun of engineers because YOU couldn't explain how his bowl was filling...
As far as I see, there still exists the question, "Why is his particular bowl filling if the fill tube is not in the hole." It is a FACT that it is, and it also appears to be a FACT that it is not filling through the flapper hole.
'Splash-back?' I don't believe that in a second. That would mean that dirty toilet water is what was filling his bowl. Left-over water that would contain e-coli and waste would be coming back into his bowl? Someone is wrong here and it isn't the engineer.
So, I am the type of person what wants a real answer... not a pretend answer.
Why is his particular toilet filling-up with water when the tube is not in the fill hole?
Even the engineer's explanation makes no sense. By the theory, there should be no water at all in the area where the holes are at any time unless it went through the filler tube. "Something is not right in Denmark!"
...
However, the engineer had a very valid question - which was never really answered properly.
Using 1970's toilet theories, there is absolutely no way that the bowl ever would have filled if you didn't have that little tube over the fill tube unless there were water leaking through the flapper valve because, by the theory - the water goes into that tube, through the holes that are under the rim and that is what fills the bowl.
That was a long time ago now.
Since then a gazillion different toilet tank designs were developed by a gazillion different manufacturers as Capitalism always has done; so there's absolutely no way to say the tube is needed or not needed for any particular toilet unless a person specifies the particular toilet design.
The facts are, he held the flapper ball down as it flushed, covered it with plastic, so by the theory - the only way that water could get into the bowl by conventional theories would be through the plastic tube - and if the plumbers had been correct by the generic theory - there is no way that water would go into his bowl - period.
But that didn't happen.
His bowl IS filling up and it is filling up to the correct level.
So, the ones who are being immoveable on the subject are the plumbers, not the engineer. The engineer is (still) confused as why his bowl is filling up to the proper level (as he should be).
After reading all these threads, I still have the question, "Why is his toilet bowl filling-up if the flapper ball is not leaking?"
The answer has to be that that particular toilet must have some advent to water entering the area where the holes are OTHER than through the plastic overflow tube; and that is what intrigues me. You can't get around the fact that water IS filling up in his bowl, PERIOD. And, apparently that water is not leaking through the flapper.
What?
I have found that people in professions oftentimes don't understand everything, themselves. They learn the 'right way' which is generally generic learning that sounds simple; but isn't always correct.
The first thing I would have asked is, "Who manufactured the particular toilet that you have?" There were a lot of posts, and maybe somoene did ask that; but it seems like it would be the first question I would have asked. I wouldn't, first, have jumped down the engineer's throat and then started making fun of engineers because YOU couldn't explain how his bowl was filling...
As far as I see, there still exists the question, "Why is his particular bowl filling if the fill tube is not in the hole." It is a FACT that it is, and it also appears to be a FACT that it is not filling through the flapper hole.
'Splash-back?' I don't believe that in a second. That would mean that dirty toilet water is what was filling his bowl. Left-over water that would contain e-coli and waste would be coming back into his bowl? Someone is wrong here and it isn't the engineer.
So, I am the type of person what wants a real answer... not a pretend answer.
Why is his particular toilet filling-up with water when the tube is not in the fill hole?
Even the engineer's explanation makes no sense. By the theory, there should be no water at all in the area where the holes are at any time unless it went through the filler tube. "Something is not right in Denmark!"
I think the explanation was that the bowl never really emptied, so it it did not have to fill. Plus there was still some water making its way through the paths to the rim holes and down the bowl after the slow siphon had broken.
The new low flow toilets flush faster.
If you turn off the supply water and flush, I think you would find that an old slow toilet will have more water left in the bowl than a more modern toilet with the smooth trapway.
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Jadnashua
Retired Defense Industry Engineer xxx
ON a well designed, low-flow toilet, at the end of the functional flush, the bowl is almost literally empty. The last of the waste and original water from the bowl and what was dumped in there is just plain already gone. Adding more water by keeping the flapper open (it may only be part of a second) may not introduce enough new water for the bowl to flush again, but essentially then leaves it full (you have to stop the flow before the flush is done, so that when it finishes, your bowl isn't already full again). If the flapper stays open even a small bit too long and refills the bowl, you probably don't need the overflow tube. Many toilets use a siphon jet, and when you flush, some of the water goes that path to get things moving rapidly, and some falls from the rim to help rinse the sides. The overflow tube and the hose from the fill valve during the tank fill tends to let more water run down the rim to help clean the upper portion of the bowl, not underneath water when static. So, even if it doesn't need that water to refill the bowl, it may mean less rinsing of the bowl is possible. The key to this is the actual design of the flapper and its ability to shut off when designed to minimize overall water use. Getting this balancing act perfected and reliable often means selecting some specific parts. If you don't care about overall performance and efficiency, I guess, if it flushes what you want, you'll be happy. People living in the parched west need to start looking at things more closely, and everyone should get involved even if they currently have enough potable water. It's a finite resource, and a recent study has shown nearly all aquifers on earth are being drained faster than they are being recharged. When I lived in ElPaso, TX, there was an article in the paper indicating research showed that they were pumping up water that had been aged at over 10,000 years...things were a lot different 10,000 years ago, the ice age, and those areas supported lush grassfields. It's scary that it might take another 10K years to replace the water you're drinking now. No wonder the levels are dropping and the water quality is going down.
Eric C
New Member
I'm neither a plumber nor an engineer. My collegiate studies were in physics. I wanted to address the siphon issue, as I think there is simply a misunderstanding as to why the precaution is needed. Obviously, it has nothing to do with the water siphoning into the main, as even if there was sufficient pressure in the tube, it would still have to bust through the closed fill valve itself. The danger is it siphoning out of the tank and into the overflow.
The fill valve shoots water into the toilet in two places, directly into the tank via little holes at the bottom of the assembly, and through the bowl refill tube, which is usually shoved into the overflow pipe. If the water flowing to those two places stays connected even after the valve is shut off and the tube is low enough, the tank water would begin to siphon out. It will continue to siphon until the water level in the tank reaches the height of the end of the tube. If that height is below the fill height, it will trigger the water to come on. I've provided a diagram.
Of course, the heart of science is empiricism. I tried lowering my refill tube well below the tank fill level. Lo and behold, after the tank filled up, I heard drip-drip-drip followed by an eventual re-activation of the fill mechanism. I think that qualifies as experimental support. Granted, this doesn't mean that all fill assembly designs suffer from this potential problem, but there is clearly merit in exercising the precaution.
The fill valve shoots water into the toilet in two places, directly into the tank via little holes at the bottom of the assembly, and through the bowl refill tube, which is usually shoved into the overflow pipe. If the water flowing to those two places stays connected even after the valve is shut off and the tube is low enough, the tank water would begin to siphon out. It will continue to siphon until the water level in the tank reaches the height of the end of the tube. If that height is below the fill height, it will trigger the water to come on. I've provided a diagram.
Of course, the heart of science is empiricism. I tried lowering my refill tube well below the tank fill level. Lo and behold, after the tank filled up, I heard drip-drip-drip followed by an eventual re-activation of the fill mechanism. I think that qualifies as experimental support. Granted, this doesn't mean that all fill assembly designs suffer from this potential problem, but there is clearly merit in exercising the precaution.
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Bluebinky
Member
Hey, I'm an engineer and the idea of the small hose siphoning from the submerged outlet-side of the fill valve into the overflow tube kinda makes sense to me 
-- and at least part of why it takes forever to get new planes off the ground because the bean counters insist on outsourcing everything to 1000 different companies.
However, I do sometimes have trouble with advanced plumbing math like when the plumber fixes my problem in 15 minutes and charges $100. Wow -- I should be a plumber, they make $400/hour of pure profit!
EDIT: nice drawing of the siphon Eric C.
-- and at least part of why it takes forever to get new planes off the ground because the bean counters insist on outsourcing everything to 1000 different companies.However, I do sometimes have trouble with advanced plumbing math like when the plumber fixes my problem in 15 minutes and charges $100. Wow -- I should be a plumber, they make $400/hour of pure profit!
EDIT: nice drawing of the siphon Eric C.
----_______________________________________LOL
If Engineers are so useless then how come Plumbers don't design aircraft?
Good to see the kid is not following in Father's footsteps.
Geeze, some of you guys are twitchy about being challenged on long-held beliefs. Old Arabian Proverb, "Arrogance diminishes Wisdom."
I just checked your statement - plugged that "little hose" with a plug to stop water flow........toilet is filled up with water. No need for that "little hose" . Can buy $8 valve WITHOUT OPENING for a hose (if someone like to see the hose, he/she can cut off the plastic top).
Will work fine - just checked it!!
Flapper lets the water to go down in just right quantity
Thanks for stating the obvious!
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Jadnashua
Retired Defense Industry Engineer xxx
FWIW, most toilets will NOT refill the bowl if you do not have the hose to do it via the overflow tube. If your toilet is designed to not need it, and you have one, you'll be wasting water. To get a super flush with the minimal amount of water, nearly the entire bowl gets siphoned out. Letting more water out of the tank often causes water to be wasted.
WJcandee
Wise One
Wow, I had never seen this idiotic thread before.
The engineer was such an arrogant tool that I almost wonder if he wasn't a troll -- someone messing with us -- but sadly I think he just didn't realize that he sounded like so much of a jerk.
If the refill hose wasn't necessary to assure a proper refill, toilet manufacturers would ditch it and instead use the refill water as part of the flush so as to meet the Watersense requirements more easily. If they put it in the toilet, then it's necessary. On most 1.28 gallon Totos, .28 gallons is refill water and 1 gallon is flush water. That's a lot of water that could be more-profitably used to give the flush more oomph if it wasn't necessary for the refill.
And there was a fatal flaw in the engineer's argument that I must mention: he was defining a "properly-refilled" bowl NOT as the bowl level where the water just touches the weir (i.e. the "settle level"), but rather as what his bowl had always been, which is who-knows-what level. Engineers should always check their premises. He didn't, and his argument was based on a false premise.
However, even if that was the settle-level, the more likely explanation for the phenomenon he was describing is that the flapper was staying open too long, and inducing water into the bowl after the siphon had completed. Maybe the wrong flapper. Maybe something else.
But this "Eureka! I, genius that I am, have discovered a flaw in toilet design!" garbage was just gag-inducing.
I won't even get into the refill-hose siphon stuff. Toilet manufacturers and fill valve manufacturers, who both employ engineers experienced in the design and operation of toilets, both tell you to daylight the refill hose above the fill valve out of concern that the tank water would siphon. They wouldn't bother with this if they didn't know it was a valid issue.
The engineer was such an arrogant tool that I almost wonder if he wasn't a troll -- someone messing with us -- but sadly I think he just didn't realize that he sounded like so much of a jerk.
If the refill hose wasn't necessary to assure a proper refill, toilet manufacturers would ditch it and instead use the refill water as part of the flush so as to meet the Watersense requirements more easily. If they put it in the toilet, then it's necessary. On most 1.28 gallon Totos, .28 gallons is refill water and 1 gallon is flush water. That's a lot of water that could be more-profitably used to give the flush more oomph if it wasn't necessary for the refill.
And there was a fatal flaw in the engineer's argument that I must mention: he was defining a "properly-refilled" bowl NOT as the bowl level where the water just touches the weir (i.e. the "settle level"), but rather as what his bowl had always been, which is who-knows-what level. Engineers should always check their premises. He didn't, and his argument was based on a false premise.
However, even if that was the settle-level, the more likely explanation for the phenomenon he was describing is that the flapper was staying open too long, and inducing water into the bowl after the siphon had completed. Maybe the wrong flapper. Maybe something else.
But this "Eureka! I, genius that I am, have discovered a flaw in toilet design!" garbage was just gag-inducing.
I won't even get into the refill-hose siphon stuff. Toilet manufacturers and fill valve manufacturers, who both employ engineers experienced in the design and operation of toilets, both tell you to daylight the refill hose above the fill valve out of concern that the tank water would siphon. They wouldn't bother with this if they didn't know it was a valid issue.
WJcandee
Wise One
Eric C -- nice job!
Bluebinky -- you have left out the drive-time component. If only they could go from one job to another and do four in an hour. If they can do one an hour, they are lucky. Then there is gasoline, insurance on the van, liability insurance, carrying cost of inventory, payments on the money they borrowed to buy and replace tools, chargeoffs, cost of running the office (person, space, consumables like paper, toner, etc.), bank and credit card fees, that yellow pages listing, and on and on. If revenue is $4000/wk and cost of operation is $3250, folks aren't taking home as much as one might think.
Bluebinky -- you have left out the drive-time component. If only they could go from one job to another and do four in an hour. If they can do one an hour, they are lucky. Then there is gasoline, insurance on the van, liability insurance, carrying cost of inventory, payments on the money they borrowed to buy and replace tools, chargeoffs, cost of running the office (person, space, consumables like paper, toner, etc.), bank and credit card fees, that yellow pages listing, and on and on. If revenue is $4000/wk and cost of operation is $3250, folks aren't taking home as much as one might think.
Thanks!
Yes, like any business there is more to it than what you see as the end result.
Sometimes there is a lot of discussion about the job before we even see it. Both with the homeowner and among ourselves. The time the homeowner sees is just a small part of it.
When I get a meal in a resturarant, the fact that the meal just appears doesn't account for the cooks in back, the food being delivered, those that open and close, do the book keeping and the wait staff. And all of that needs to be maintained, clean, in good working order.
When I get someone on the phone that tells me cutting and soldering a fitting in a crawlspace is a 15 minute job, I tell them I'm not interested. I don't have the time to educate those that think like that.
I have plenty of customers that know better than that. Those are the ones I take care of.
Bluebinky
Member
wjcandee, I figured everyone would know I was joking. Thanks, though...
Just like plumbers, not all engineers are created equal. What do you guys think of this "engineers" new DIY tool? I figured it would be cheaper to buy and sell later then rent a bunch of times while fixing up Dad's old place over the next few years.
WJcandee
Wise One
Dude, that machine rocks! You're going to have hours of fun!
And from the "pure profit" comment, I thought you might not be serious.
Humble Engineer
New Member
Well, it is now 2018 and the reason that I have joined this thread is that it has just taken me hours over a period of a couple of weeks to diagnose ghost flushing on a Western toilet in an apartment that we just moved into.
Flapper didn’t look too bad but I replaced it anyway. Seat on flush valve looked fine. Took tank off (twice), gasket below flush valve looked a little rough but I still couldn’t believe that it was leaking especially after I cleaned it up and refitted it, tank bolt gaskets had started to deteriorate but I figured that if they were leaking, I’d see water on the floor or corrosion on the bolts.
I had looked down the overflow tube a few times and thought I heard something between flushes but didn’t pay enough attention.
Fact is that I could not see the flow because the tubing was touching the side of the overflow tube and it was only when my flashlight caught the reflection of the ripples of water at the bottom of the overflow tube that I realized that I had a SIPHONING problem.
I then figured out what was going on, fixed it by cutting the tubing so it was well above the tank water level…and problem solved.
I went online to see how much discussion there was about this and I certainly got more than I expected here!
For those of us who truly want to understand what is going on with the cause of this, this string has been very interesting, and I think the last few posts, particularly the diagram from Eric C, have been very useful.
I’d like to add the following to Eric’s diagram.
Obviously the ports at the bottom of the fill valve and the nipple that feeds the black refill tube are connected during the fill cycle and after the fill cycle completes, this remains so. Therefore the incoming water pressure has absolutely nothing to do with the ability for a siphoning action to take place, as brought up much earlier in the thread.
Some parting comments:
Some engineers can be very arrogant and this is particularly annoying when they don’t know what they are talking about.
This is one reason that a lot of tradespeople don’t have much time for engineers and I get that. However, it’s also a fact that quite a few tradespeople are not very good at explaining why things happen. They just know from experience why things should be done a certain way.
You would think that we would all be saved by the instructions that come with replacement fill valves (like the Fluidmaster 400 series) but the problem is twofold.
First, the vast majority of people don’t read instructions because they are lazy or think that they know better.
Secondly, unfortunately those who write instructions don’t usually explain the reason for the instruction, for instance “don’t allow the black refill tubing to project any more than an inch or so into the overflow tube and certainly not anywhere near the fill level of the tank or there is a great possibility that a siphon will be established and the tank will lose water between fills causing ghost flushing”.
By the way, I am a licensed Mechanical Engineer but I hope I never stop being interested in getting to the bottom of problems, being open minded about the views of others and I hope that I don’t ever come across as being arrogant (especially when I might be wrong or even misguided!).
Flapper didn’t look too bad but I replaced it anyway. Seat on flush valve looked fine. Took tank off (twice), gasket below flush valve looked a little rough but I still couldn’t believe that it was leaking especially after I cleaned it up and refitted it, tank bolt gaskets had started to deteriorate but I figured that if they were leaking, I’d see water on the floor or corrosion on the bolts.
I had looked down the overflow tube a few times and thought I heard something between flushes but didn’t pay enough attention.
Fact is that I could not see the flow because the tubing was touching the side of the overflow tube and it was only when my flashlight caught the reflection of the ripples of water at the bottom of the overflow tube that I realized that I had a SIPHONING problem.
I then figured out what was going on, fixed it by cutting the tubing so it was well above the tank water level…and problem solved.
I went online to see how much discussion there was about this and I certainly got more than I expected here!
For those of us who truly want to understand what is going on with the cause of this, this string has been very interesting, and I think the last few posts, particularly the diagram from Eric C, have been very useful.
I’d like to add the following to Eric’s diagram.
Obviously the ports at the bottom of the fill valve and the nipple that feeds the black refill tube are connected during the fill cycle and after the fill cycle completes, this remains so. Therefore the incoming water pressure has absolutely nothing to do with the ability for a siphoning action to take place, as brought up much earlier in the thread.
Some parting comments:
Some engineers can be very arrogant and this is particularly annoying when they don’t know what they are talking about.
This is one reason that a lot of tradespeople don’t have much time for engineers and I get that. However, it’s also a fact that quite a few tradespeople are not very good at explaining why things happen. They just know from experience why things should be done a certain way.
You would think that we would all be saved by the instructions that come with replacement fill valves (like the Fluidmaster 400 series) but the problem is twofold.
First, the vast majority of people don’t read instructions because they are lazy or think that they know better.
Secondly, unfortunately those who write instructions don’t usually explain the reason for the instruction, for instance “don’t allow the black refill tubing to project any more than an inch or so into the overflow tube and certainly not anywhere near the fill level of the tank or there is a great possibility that a siphon will be established and the tank will lose water between fills causing ghost flushing”.
By the way, I am a licensed Mechanical Engineer but I hope I never stop being interested in getting to the bottom of problems, being open minded about the views of others and I hope that I don’t ever come across as being arrogant (especially when I might be wrong or even misguided!).
John Gayewski
In the Trades
Look at the picture above your post. It's called the refill tube. Take the old one with you and get any tube that is similar.
John Gayewski
In the Trades
I really wish I would've been in on this thread when it started 10 plus years ago. I skimmed it and wanted to jump in so badly, lol.
LLigetfa
DIYer, not in the trades
You dredged up the wrong thread. Now folks will add their two cents to the original discussion that is unrelated to your problem. You would have been far better off starting a new thread rather than dredge up a more than a decade old long thread.
Actually, the tiny hose being discussed in this thread is not for filling the tank back up but rather for refilling the bowl, a point clarified in my answer at the start of the thread. There is likely a second larger rigid tube from the valve directed straight down that has clogged due to hard water.
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