Slow flushing toilet diagnosis & repair FAQs #2:
This article series will help you diagnose and repair toilets that flush too slowly or have a weak flush, or that are backing up.
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These questions and answers about slow-flushing or poor-flushing or incompletely-flushing toilets were posted originally at TOILET FLUSHES POORLY - please be sure to review the poor-flush diangosis and repair advice given there.
On 2019-02-23 by (mod) - odors and occasional leaks at suspect toilet wax ring seal - vent issues too?
I agree it sounds like leaky toilet flanges at the least.
Sometimes a toilet may be securely-bolted to the floor, but its wax-ring seal can be damaged and leaky. Leaks may be apparent only as odors until there is a slow or partly-clogged drain - then wastewater may seep out around the toilet base or even into the subfloor or ceiling or slab below.
If the problem were the vent system I'd expect to notice slow or gurgling drains at other fixtures served by the same vent.
On 2019-02-22 by Brody
Hello! Our main floor toilet often has a weak flush and sometimes the bathroom smells like sewage. It seems like the two events are connected, because when the bathroom smells fine, the toilet flushes fine.
When I went downstairs and looked at the floor under the toilet, there are old water marks but the floor is dry and nothing seems like fresh leakage.
Also, there’s never any water that leaks out from below the toilet onto the bathroom floor, so I’m not sure if it’s a wax ring issue or not.
Also, our vent pipe is quite short, maybe 1’ long. We have deep snow, and digging it out helps, but we’ve experienced this same problem in the summer time.
I’ve heard of short vent pipes being effected by down drafts and wind. Could adding an extension to the pipe possibly fix our issue?
On 2018-07-09 1 by Blah
When i flush my toilet it doesnt really seem to flush then this morning after flushing the toilet, it started smelling really bad, and now there is feces in my bath tub. Any idea on what the problem is.? Just started renting this home.
On 2018-03-09 by (mod) - signs of partial drain blockage
Sounds like a partial blockage in the drain line
On 2018-03-08 by AWilson - the bowl fills, then the water recedes,
Our toilet flushes waste away just fine, but sometimes the bowl fills, then the water recedes, many times all the way down and we get gurgling.
On 2018-02-16 by (mod) - virtually all toilet parts are replacable,
Yes Paece virtually all toilet parts are replacable, if not with an exact match with a generic substitute.
On 2018-02-15 by Paece
Can ball cocock be replace
On 2018-01-07 by (mod) -
That sounds like a blocked drain. Sometimes you can free a clogged toilet by plunging for a longer time than you thought necessary - give it more time and effort and let me know.
Else it's time to call a plumber who can run a toilet auger snake through the drain to clear it.
On 2018-01-04 by Anonymous
When trying to flush, water fills the toilet bowl but waste does NOT get flushed away. Water will then SLOWLY drain down completely. Waste still present. Tried plunging and no difference.
On 2017-04-21 by (mod) - Can a slow flushing toilet impede the septic
Paula
More likely the other way around: if the toilet is flushing poorly and if the cause is not traced to either inadequate water in the flush tank or a clogged main drain, then the septic system may itself be flooded and in failure.
When the toilet is flushed wastewater (solids and liquid) flow into the septic tank. Baffles try to keep solids in the septic tank; but at that same time a like volume of wastewater is pushed out of the tank into the soakbed or drainfield.
On 2017-04-21 by Paula
Can a slow flushing toilet impede the septic i.e. does go into septic right
On 2017-02-11 by (mod) - adjustments and one repair determine the volume of water left in the toilet bowl after a flush:
Frank:
There are several features and adjustments and one repair that dominate the volume of water left in the toilet bowl after a flush:
1. the flow rate and quantity of water sent through the fill tube into the top of the overflow tube during tank-fill: on some toilet fill valves the tube may be crimped or the flow rate poor due to clogging in the valve itself, or of course on some the tube may be out of place and not sending water into the bowl
2. the duration of the fill cycle and water pressure and flow during that time
3. the adjustment of the lift chain on the toilet flapper and the volume of water that is thus sent into the bowl during the flush
4. a clogged drain line: slow flush may consume more of the bowl water
I'm not sure what sediment you are seeing: I'd consider replacing the fill valve assembly and flush valve. Inexpensive and a good bet if there's no sign of clogging and if water pressure is good.
On 2017-02-10 by Frank
My toilet tank fills up to the normal level, however, the toilet bowl does not. The bowl only fills up about 1/3 full of water. The only way I can get the water in the toilet bowl to fill up to the normal level is if I turn off the stop valve and immediately turn it back on.
After a flush, refill tube and overflow tube appear to be working properly, as does the float ball. Could there be an issue with the flush valve and/or flapper? I've noticed a bit of fine gray sediment which has appeared in the very bottom of the toilet bowl. Are these related to my problem?
On 2017-01-31 by (mod) - if plunging doesn't do it
If patient and prolonged plunging with a toilet plunger doesn't clear the drain you'll want to call a plumber who, using a power snake, can probably grind and clear the obstruction. I'm doubtful that a liquid drain cleaner will dissolve a paper napkin blockage.
On 2017-01-31 by Saundra
Live in apartment building...toilet is slow flushing (it's my fault...accidentally flushed paper napkins). The plunger isn't doing anything. Water is going down, but then the bowl doesn't refill. Occasionally, I will hear it "glugging" and when I check, the bowl is almost empty of water.
Some feces did get removed, but not all. Urine seems to be moving out, but again, no water is coming back into the bowl.
The bowl does want to overflow when I flush, but I immediately stop the water from rising too high. I've used CLR bathroom cleaner. I've tried the dishwashing detergent option.
I'm thinking about trying a Liquid Plumbr/Drainer type thing. Any other suggestions before I spend the cash?
On 2016-11-06 by josh - slow flushing floor toilet with flushometer valve.
I have a slow flushing floor toilet with flushometer valve. Toilet flushes very slow, even if i try using a bucket of water. Toilet in the washroom next door flushes fine, with valve operation or bucket. They are next to each other in my commercial building, i though perhaps a clog or venting issue but wouldn't that affect both toilets?
On 2016-11-05 by (mod) - diagnose slow flush toilet
There is normally NO reason to replace an entire toilet just because it flushes poorly. Worse, the new toilet may flush poorly too if the problem is the drain or vent.
If the problem is NOT in the drain or vent piping then the problem is with toilet adjustment
Key in your description is
The only way the toilet works is if I hold down the handle for about 30 seconds.
That tells me that the toilet flush voume is not enough; check that the water level in the cistern (tank) is at least to the water line marked inside the tank.
Following that repair if the toilet is still slow I'd check for inadequate venting, a blocked vent, or a blocked drain.
On 2016-11-05 by Joanne G - slow flushing toilet
Hi there,
I have had a slow flushing toilet for years, I've come here as a last resort before I spend some of my hard earned savings on hiring a plumber to replace it.
I have three 20 year old toilets, the toilets in the basement and the third floor work great. The toilet on the second floor does not. I keep it very clean and over the years I've tried the following thing and repeated them again this morning:
I've tried the bucket test and the water drains quickly
I've adjusted the water line to slightly higher
I've tightened the flapper chain
I've moved the styrofoam float closer to the flapper
I've checked all of the holes (jets?)under the seat. They seem clean. I gave them a poke with a wire coat hangers but not much came out.
I've tried plunging and checked the main jet.
All of things things have helped marginally, it's gone from really bad to just bad.
The only way the toilet works is if I hold down the handle for about 30 seconds. With just a regular handle movement, the flush starts fairly strong but quickly peters out. Even with the flapper adjustments, the flapper still seems to close too soon which slows down the flush considerably.
Is there anything else I should try?
Is it worth calling a plumber
Should I just pay someone to replace it (since I don't have these skills myself)?
Much appreciated!
Joanne
On 2018-08-20 by (mod) -
Sounds as if the fill/flush valve assembly should be replaced.
On 2018-08-20 by MrsM
My toilet is being weird.
It has two buttons; fast/quick flush which is fine and then the longer flush. When you press and hold the button in to ensure that 'everything' in the toilet has gone,
my toilet then rapidly fills with clean water nearly to point where it nearly spills over, and then its make this vacuum type noise and gargles really loudly and then it all disappears and i'm left with a small amount of water at the bottom of the toilet.
It has only started doing this recently. Any ideas? Do I need a plumber?
On 2018-05-07 by (mod) - my system makes a noise after flushing
What sort of noise?
For example: gurgling drains often mean that there is a clogged drain downstream from the toilet.
On 2018-05-04 by Anonymous
WHyde does my system make a noise after flushing
On 2017-08-05 by Pam
My toilet seems to flush just fine but small pieces of residue fall back into the toilet minutes after flushing, even after flushing a clean bowl.. iAny suggestions?
On 2017-06-20 Chuck Rasch
I live in a condo with three toilets, no problem for 15 years then a few days after getting a new roof toilets won't flush properly. The first attempt to flush results in the bowl filing almost to the top and then drains slowly, sometimes taking the waste, sometimes not, or partially. Flush a second time and it works properly. Also when flush one toilet the water in another one bubbles up.
On 2017-06-20 y Wayne
Thanks Bernie for the quick reply, I have these low flow Totos toilets for over five years and never any problems til today. High volumns of tissues tossed into the bowls started the problems by the youngster. The toilets are cleared, but the slow drains seem like it might be blocked air vents as I read in these comments. How can that be ? I haven't been up on the roof..
The toilets are still draining slowly and draining into the bath tub. Does that mean the clogs are still within our drains and not not in the sewer line?
On 2017-04-04 by (mod) -
Bernie
When a toilet flushes successfully several times and then backs up I suspect that there is a main drain blockage that is distant from the toilet itself.
On 2017-04-04 by Bernie
I'm in a condo unit, 14th floor. The toilet backs up, even with just water. I've plunged it. I had a plumber in who snaked it, then I pulled it up, checked the trap from below and also the line out. Everything looks clear, it flushes fine about 10 times, then backs up again. Any ideas?
On 2017-01-08 by (mod) - commode will not flush all contents.
Oops, sorry Rod I accidentally deleted your email posting.
Check for a toilet bowl or tank or both that are not filled to the proper level with water after a flush
Check for a partly blocked or clogged drain. This seems the more likely problem as you say the drain is slow.
If you hear gurgling at nearby sink or tub when toilet is flushed check for a blocked plumbing vent
On 2017-01-08 by Rod Fryrear
commode will not flush all contents.
commode will flush fast enough to remove all waste in bowl--flushes slowly.
On 2016-07-14 by (mod) - slow filling toilet cister
Simplest fix, assuming that building water pressure is good at fixtures, is to replace the toilet fill valve assembly; The old one may be worn or clogged.
On 2016-11-20 by Anonymous - slow filling toilet tank
SLOW FILLING TANK
My monther's tank started filling very slowly. At first, if I shut off the water supply to the toilet & turned it back on, if would fill normally.
Now sometimes it will fill normally & other times it will fill slowly.
I replaced the toilet's inner mechanisms less than 10 yrs ago and haven't had a problem since. But this seems to be more related to the supply and not the toilet itself.
What do you think?
Bothered in Bethlehem
On 2016-07-15 15:37:37.792879 by (mod) -
Sounds like a clogged drain that is causing backup when more water runs into the drain system; or if you're on a septic system the system may be blocked or failing.
On 2016-07-14 by pinacoloda1
My toilet bowl empties ok but then some of the contents come back up.,
Its not clogged,maintenance checked it. Always happens to me
not them,its very frustrating! So they're assuming everythings ok..
(Sept 11, 2014) Anonymous said:
My poorly flushing toilet problem was solved with the dishwashing detergent tip; then increasing the water level in the tank should help keep things moving along.
This is one of the best "how to" sites I have used. Thank you
[Click to enlarge any image] At left: the toilet flush tank or cistern usually contains a mark indicating the proper fill-line or water level in the flush cistern.
Thanks for the feedback Anon, it will assist other readers.
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