Test to Determine if Drain is Vented
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Austin, I have been sitting here trying to think of a way to answer your question. I guess the answer as far as I'm concerned is I don't know.
John
John
The toilet it self doesn't need a vent to drain. But it needs a vent to prevent it from being siphoned from the use of other fixtures.
John
John
AQualityPlumber
Plumber
If a fixture is not vented properly it will most likely drain slow and or burp air this is visibly a parent in a toilet. You will see it burb like a milk jug when you turn it upside down. Other than that it is hard to tell without seeing the pipes.
Beni
Well-Known Member
Most plumbing codes other then UPC (california, navada for two) allow wet venting or circuit venting. So many times the toilet will be wet vented by say the lavatory. Texas allows wet venting. It works fine that way and is allowed by code in all the southern states. Actually the new UPC allows it too but many inspectors still don't like it.
If there was an improper vent installation you would get sewer smells from the sink drain or from the tub shower. This as the toilet flush would be siphoning the other traps.
No easy way to test that though. The trap / vent design in modern plumbing design limits the pressure differential to 1" water column. Most traps btw have a 2" W.C limit before they will siphon. Thats not a lot of pressure, about 0.05-0.08 ish psig.
If there was an improper vent installation you would get sewer smells from the sink drain or from the tub shower. This as the toilet flush would be siphoning the other traps.
No easy way to test that though. The trap / vent design in modern plumbing design limits the pressure differential to 1" water column. Most traps btw have a 2" W.C limit before they will siphon. Thats not a lot of pressure, about 0.05-0.08 ish psig.
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I have to back the bus up a little and ask this: What is the toilet doing that would bring the question of venting into issue? Are there other fixtures that are responding to the toilet's use? Is this on a !st floor, 2nd floor or under concrete slab?
A clog is sometimes misdiagnosed as a venting issue and vice versa. Typically it is a clog or partial obstruction. You could get siphoning of the toilet trap, other nearby fixtures (tubs/showers) as well as air gurgling after a flush in the toilet and other parts of the drainage system.
A clog is sometimes misdiagnosed as a venting issue and vice versa. Typically it is a clog or partial obstruction. You could get siphoning of the toilet trap, other nearby fixtures (tubs/showers) as well as air gurgling after a flush in the toilet and other parts of the drainage system.
It is also important to know if this is a new problem or has always existed and if there have been any modifications to the drainage system prior to the appearance of the issue.
We noticed a bit of a sewer smell. It's a two story home and I see a single vent on the roof for a total of 2 toilets, 4 sinks and 2 showers. All the bathrooms are on the same side of the house above each other.
It's possible that all of your vents connect to the stack vent before exiting through the roof of your home to reduce the number of penetrations through the roof. Unless you can pin-point the toilet as the cause of the odor, there are a number of situations that can cause a sewer odor from a fixture.
The wax ring could be allowing gases out between the flange and the bowl if it has lost its seal. It usually doesn't lose its seal unless it has degraded over a long period or if there has been a clog in the drain beneath it and water pushed through the seal.
Sinks that gather a lot of hair or soap scum can develop a sewery smell. If you can, remove the pop-up and trap to see if the tailpiece is all boogered up inside. Shining a flashlight from below (where the trap was removed) will give you a good view of how clear it is.
A clog further down the drain of a sink or tub/shower could cause a loss of trap seal and allow some gasses to pass through. Pouring a pitcher of water slowly down the drain and listening for a 'glug' sound as well as looking down into the trap with a flashlight may give you some insight as to if a clog is the problem.
The overflow of the sink is another common culprit. Close the pop-up and fill the sink. Let the water go and put your nose next to the overflow hole. Build up and mildew inside the overflow and where it connects to the drain tailpiece will stink like a sewer, too. If this is the problem, try to find a funnel that will fit into the overflow hole. Mix a gallon of warm (not hot) water with one cup of bleach ( 1:16 ratio, bleach to water respectively) and pour it into the funnel to rinse the overflow.
Also relating to overflows, a tub with a pop-up assembly that has hair and stuff on the plug/linkage will stink from the overflow, too.
Hope this info points you in the right direction to resolving your problem. It's kinda hard to put a finger on it without being there to see, but follow up with us and I'm sure others will have have more input on the matter. -Scott
The wax ring could be allowing gases out between the flange and the bowl if it has lost its seal. It usually doesn't lose its seal unless it has degraded over a long period or if there has been a clog in the drain beneath it and water pushed through the seal.
Sinks that gather a lot of hair or soap scum can develop a sewery smell. If you can, remove the pop-up and trap to see if the tailpiece is all boogered up inside. Shining a flashlight from below (where the trap was removed) will give you a good view of how clear it is.
A clog further down the drain of a sink or tub/shower could cause a loss of trap seal and allow some gasses to pass through. Pouring a pitcher of water slowly down the drain and listening for a 'glug' sound as well as looking down into the trap with a flashlight may give you some insight as to if a clog is the problem.
The overflow of the sink is another common culprit. Close the pop-up and fill the sink. Let the water go and put your nose next to the overflow hole. Build up and mildew inside the overflow and where it connects to the drain tailpiece will stink like a sewer, too. If this is the problem, try to find a funnel that will fit into the overflow hole. Mix a gallon of warm (not hot) water with one cup of bleach ( 1:16 ratio, bleach to water respectively) and pour it into the funnel to rinse the overflow.
Also relating to overflows, a tub with a pop-up assembly that has hair and stuff on the plug/linkage will stink from the overflow, too.
Hope this info points you in the right direction to resolving your problem. It's kinda hard to put a finger on it without being there to see, but follow up with us and I'm sure others will have have more input on the matter. -Scott
Additionally, I never asked if this is isolated to one room or if it's throughout the house...oopsie. Let me know.
Beni
Well-Known Member
There is a chance there could be a pinhole leak in the china toilet. I've seen that happen once or twice too. It happens sometimes. So check around the back side of the toilets.
It's not isolated and I cannot pinpoint it's location. Just that portion of the house has a sewer funk to it.
I wish there was a way without ripping out of ceiling/wall to see if that vent is from the plumbing.
I wish there was a way without ripping out of ceiling/wall to see if that vent is from the plumbing.
Austin, you could do a smoke test that would locate the source of the sewer order if that is what your smelling.
John
John
