An AAV adds a vent and let's air into the system. It keeps the trap seal from being siphoned. It doesn't add water to the trap. What you described is a trap seal primer.
@LRN2DIY You got AAV mixed up with a trap primer. An air admittance vavle does exactly what it says, it allows air in to the system to break the vacuum in the system if you dont have adequate venting. A trap primer is used to refill the trap with water every so often usually used in mechanical rooms for traps that accept condensate lines and t&p valves.
I was just about to state the above... An AAV prevents siphoning of the trap... A trap primer eliminates dry trap. You can also use a waterless trap, which has a check valve for locking out sewer gas.
@@artking1729 Wrong but thanks for playing. The word 'crap' predates 'Crapper' and his business by more than a decade. That's more than ten years BEFORE.
Great video Thank you! I’ve been having a smell issue in one of my bathroom sinks and could not figure out what the issue could be With this video I have a few things that I can double check and hopefully clear up the issue Thank you
My parents had the same problem with their bathroom sink. It turned out that the P-trap was being sucked out because the washing machine drain, which was on the other side of the wall, was creating a vacuum on the pipe every time it emptied. The plumber did a poor job of hooking the sink and the washing machine drain onto the same pipe. I was able to easily fix that for them by installing what is called an "air admittance valve" next to the wall under the sink. That way when the washing machine started to empty and created a vacuum, it would allow air to flow into the pipe rather than suck the water out of the bathroom sink P-trap. Have not had a problem with stink since then.
Most are so short it would not make a difference. As long as they are not sloped upwards you would be good. But if it goes from one side of the cabinet to the other to connect to the main sewer line, like under a double or triple sink cabinet, a slight slope downwards from the trap would be a good idea. The main idea is that you do not want the post trap line to fill with water since that can create a siphon and pull the water out of the trap. That was the problem with S-traps and why they are no longer allowed.
That little inspection dohickey you mentioned in this video, was on the "P" traps when I was a little boy, and I was borne in the first half of the last centry.
Excellent video! The history was interesting, and a very good explanation of a p-trap! I've done little plumbing repairs. Last year, I had to replace the valve stems (like in a bathroom faucet), used for the washing machine in the garage. Bit of a mess! I now have to remove a broken food waste disposer, decided to replace with a sink strainer. The plumbing is a mess, nothing for airflow, will check the roof in the am. Did not know about the slope and there is currently no slope, so need to get a small level. I will be viewing your 'Plumbing for Homeowners' videos! One question, is that see-thru piping a real thing that one could use or just for clarity of explanation in the video? Thanks much!
OK, youtube will let me reply to myself. So, that clear piping does exist. Did a search and it's called "Clear Schedule 40 & 80 PVC Pipe and Fittings 1/2" - 12" Pvc Pipe Crafts, Pvc Pipe Projects ..." Will look into it more, after I fix the current broken disposal problem, and see what it's intended use is..
I have a very small drain system. I have a 1 1/2 inch water drain pipe. I have a kitchen sink and right thru the wall there is a bathroom. There is a drain pipe that passes thru the wall horizontally. I want to ad a bathroom sink to it, can I do that?
Hi! Thank you for making this video. I'm watching it..but as I do...I am wondering living in TX on a rental property the house we rent does not have a garbage disposal. We've been. Diligent to not put food down the drsin...however in the last two or three weeks here this is the 4th time we've had to get under the sink and clear the pea trap...did the landlord do something they shouldn't have when the house (2019 built) was constructed? It's just weird that we have had to almost every week or every other week take care of this issue after 10 months
I have a slight sewage smell coming from under my bathroom sink. After watching your video it appears that the line coming off of the p-trap going into and behind the wall may not (???) be angled enough. Is there a way to correct that without tearing the walls open of my new home?
There is, yes. If you can raise the p-trap connection up a 1/4" that might be all it takes and often times a sink drain will use slip fittings so you can literally just loosen the fitting, slide the fitting up and then tighten. Keep in mind that as little as 1/4" of slope per foot is all that's required for proper drainage, but 1/4" to 3" per foot is the range.
is it a bad idea to take these apart to clean them? I didn't know anything about kitchen sink plumbing but took mine apart because there was a bad odor. Cleaning them cured the odor issue but now the sinks are backing up, and I'm worried I ruined the vaccuum seal or whatever and not sure what to do now.
It’s not called an air admittance valve (AAV); it’s called a trap primer. A trap primer keeps unused traps filled with water so the water in the trap doesn’t have a chance to evaporate.
I have a question , can you tell me why I have sewer flies /knats coming out of my bathtub drain , I've tried every online remedy and had a plumber come out and clean drains , they are still coming and more so now ,last resort going to call pest control but they are telling me.they can't garentee they can get rid of them , do u know how to get rid of these out of the drain ?
I have a P trap what also leads to my washing machine waste pipe, and I've had to unplug the washing machine waste pipe to replace my washing machine and I am sure water from the sink is over flowing in the ptrap and in to my machine waste pipe. Is that normal...
I've noticed the past year the kitchen drains smell horrible. I've done everything. they get used frequently.. I'm almost positive it's sewer gas...the drains are not clogged...and I ONLY smell it coming from the kitchen drains... not anywhere else in the house...It seems to stop if I slowly run cold water through the drain... but for whatever reason, if I turn the water on full, it doesn't help...so I'm always running water slowly for a little bit when I'm finishing up in the kitchen
so my trap only lets gas through when I run the water. any other time there is no detectable smell. the trap is new and clean and always seems to be full and not dry. I recently used clog remover in case there was anything stuck elsewhere along the line, but the flow is consistent and doesn't indicate a backup Any ideas?
@@briannamoore315 sort of, i bought a whole new p trap and extensions and cut the arm piece extension to the wall so that there is about 1 inch going into the wall - before, the extensions were uncut and there was about 5 inches going into the wall. I also cut the sink drain stem to about 1 inch into the extension that the joins the bend/p-trap. I don't know if there was something about these pieces being too long that enabled the gas to flow up, but it's largely mitigated the smell. Someone also mention to use 1 1/4 p trap rather than the 1 1/2 as it's a bathroom drain and not a kitchen drain. I'm curious if that would totally eliminate the problem. give it a try and good luck!
If you have a second home where you go once a year and usually traps evaporate causing uncomfortable situations to your neighbours, what can be the solution?
Simplest solution I think would be duct tape. Then when you come back to that house you fill up the sink or tub with the tape still on, and then rip the tape off under the water to prevent any gas to come out. Also note that H2S is often present in “sewer air” and can incapacitate or cause serious damage at even 1 part per million.
That sounds like you may have a clog or backup down the line somewhere. The water will have no choice but to back up if that happens. I think you need to look for a clog somewhere downstream of your P Trap.
@@LRN2DIY I put a snake in the drain twice 100 ft snake an replace the p trap than it’s still not draining still idk what to do I didn’t mess with the pipe or move it. I can’t get it figured out
@@ryanjames3130 Makes sense as it is actually shaped like a U and has a bend in it. As opposed to looking slightly like the letter P once it’s turned upside down and rotated 90° 🤦♂️
I think all of us are. I had to hold myself back while filming. I remember learning about him in school and we all acted our age when we heard his name :)
Yeah BUT, if you catch sight of the DISGUSTING things in that trap, then the transparent "feature" might result in you vomiting upon seeing what's in there (including drowning roaches!!). Some things you DON"T want to know.
I agree. I have a wife and three daughters in the house and the hair situation can be downright disgusting sometimes, when it comes to pulling it from drains. I love them and their hair, just not when it's turned into black slime.
I must not be very smart. I am not sure how a gas would not just push its way through the water if there was enough pressure build up. The dead animal scenario may create a vacuum but then the pressure from gas build up has to go somewhere...
@@Asdayasman Imagine just randomly throwing out the phrase "intellectually bankrupt" because you can't refute a basic true fact. You didn't pay for this video. Either you did or you didn't get anything out of the explanation before the sponsor message. If you didn't, move on. If you did, you still didn't pay anything. Now insult my mother. Maybe that'll work!
@@markw4206 I will admit that I was a bit confused by the thermal camera info as it seemed like a sidebar that was getting off topic before he announced it was a sponsor. However, this video was so informative and helped me with the exact information I was searching for (and more) that I give kudos (and a thumbs up) to the video.
Hi I live in Tijuana Mexico most places apt and hotel don't have that p trap because previous renters will always steal them when they leave to resell them , what can I do or use to stop those fumes when their is no p trap
An AAV adds a vent and let's air into the system. It keeps the trap seal from being siphoned. It doesn't add water to the trap. What you described is a trap seal primer.
I was so confused.
True
What he said, don’t make videos about stuff without doing your research
@@Dayinthelifeofawiener This video is literally fine for people wanting to understand how the trap works and how to clean it. Don’t freak out.
@@240devil1 The video should be edited so not spread misinformation then... Some people actually rely on these videos to do things correctly.
@LRN2DIY You got AAV mixed up with a trap primer. An air admittance vavle does exactly what it says, it allows air in to the system to break the vacuum in the system if you dont have adequate venting. A trap primer is used to refill the trap with water every so often usually used in mechanical rooms for traps that accept condensate lines and t&p valves.
I was just about to state the above... An AAV prevents siphoning of the trap... A trap primer eliminates dry trap. You can also use a waterless trap, which has a check valve for locking out sewer gas.
What a difference 7 minutes makes. Love the visual demonstration. 😊
Very useful information. I finally understand p traps now. Thanks!
Forgot to add... loved the plumbing history! I looked up Mr. Crapper in Wikipedia and in a few of my dictionaries for contemporary word usage. :-)
Are we just gonna act like that dudes last name wasn’t crapper and he made toilets more efficient
LOL
i came here just for this comment
In the tank, the Crapper flap(per)
Fun fact the reason we say taking a crap, stems from his last name. Not the reverse lol. We got it from him, it’s not a coincidence
@@artking1729 Wrong but thanks for playing. The word 'crap' predates 'Crapper' and his business by more than a decade. That's more than ten years BEFORE.
Great video
Thank you!
I’ve been having a smell issue in one of my bathroom sinks and could not figure out what the issue could be
With this video I have a few things that I can double check and hopefully clear up the issue
Thank you
My parents had the same problem with their bathroom sink. It turned out that the P-trap was being sucked out because the washing machine drain, which was on the other side of the wall, was creating a vacuum on the pipe every time it emptied. The plumber did a poor job of hooking the sink and the washing machine drain onto the same pipe.
I was able to easily fix that for them by installing what is called an "air admittance valve" next to the wall under the sink. That way when the washing machine started to empty and created a vacuum, it would allow air to flow into the pipe rather than suck the water out of the bathroom sink P-trap.
Have not had a problem with stink since then.
My daughters sink has been so horrible with smell 😢 and I think it’s this! Thank you!!!!
Very professionally done. Thanks very much.
The thermal imaging tip is gold!
This is a great video, I feel like i'm a certified plumber just from watching it.
Glad to know re pipe-to- wall-from-trap needs to be at a slight angle downward to wall. Good info on entire video, thanks
Most are so short it would not make a difference. As long as they are not sloped upwards you would be good. But if it goes from one side of the cabinet to the other to connect to the main sewer line, like under a double or triple sink cabinet, a slight slope downwards from the trap would be a good idea. The main idea is that you do not want the post trap line to fill with water since that can create a siphon and pull the water out of the trap. That was the problem with S-traps and why they are no longer allowed.
Great video. Informative . Educative. On point . Not too much bla bla bla
That little inspection dohickey you mentioned in this video, was on the "P" traps when I was a little boy, and I was borne in the first half of the last centry.
Thank you I will see if it’s the pipe that’s laying to flat .
Thank you! Your video helped me tremendously!
Very educational video! 👍🏼
Max. Size of p traps I notice many r small u shapes, and other longer deeper u shape. Does it matter?
Excellent video! The history was interesting, and a very good explanation of a p-trap! I've done little plumbing repairs. Last year, I had to replace the valve stems (like in a bathroom faucet), used for the washing machine in the garage. Bit of a mess! I now have to remove a broken food waste disposer, decided to replace with a sink strainer. The plumbing is a mess, nothing for airflow, will check the roof in the am. Did not know about the slope and there is currently no slope, so need to get a small level. I will be viewing your 'Plumbing for Homeowners' videos! One question, is that see-thru piping a real thing that one could use or just for clarity of explanation in the video? Thanks much!
OK, youtube will let me reply to myself. So, that clear piping does exist. Did a search and it's called "Clear Schedule 40 & 80 PVC Pipe and Fittings 1/2" - 12" Pvc Pipe Crafts, Pvc Pipe Projects ..." Will look into it more, after I fix the current broken disposal problem, and see what it's intended use is..
Great video-thanks so much! Please consider normalizing the volume as the interspersed music is quite loud. Thanks again.
Your efforts to make this usefull video are really admirable.
Thank you!
Thank you for this!! Super helpful. Great visuals. Great teaching actually
非常好的示範講解清晰！
I have a very small drain system. I have a 1 1/2 inch water drain pipe. I have a kitchen sink and right thru the wall there is a bathroom. There is a drain pipe that passes thru the wall horizontally. I want to ad a bathroom sink to it, can I do that?
excellent so well done thank you great visuals
Hi! Thank you for making this video. I'm watching it..but as I do...I am wondering living in TX on a rental property the house we rent does not have a garbage disposal. We've been. Diligent to not put food down the drsin...however in the last two or three weeks here this is the 4th time we've had to get under the sink and clear the pea trap...did the landlord do something they shouldn't have when the house (2019 built) was constructed? It's just weird that we have had to almost every week or every other week take care of this issue after 10 months
Thanks for your information
Hi. Congratulations. Good explanation.
Well made and works well.
Super video, thanks Nils!
I have a slight sewage smell coming from under my bathroom sink. After watching your video it appears that the line coming off of the p-trap going into and behind the wall may not (???) be angled enough. Is there a way to correct that without tearing the walls open of my new home?
There is, yes. If you can raise the p-trap connection up a 1/4" that might be all it takes and often times a sink drain will use slip fittings so you can literally just loosen the fitting, slide the fitting up and then tighten. Keep in mind that as little as 1/4" of slope per foot is all that's required for proper drainage, but 1/4" to 3" per foot is the range.
is it a bad idea to take these apart to clean them? I didn't know anything about kitchen sink plumbing but took mine apart because there was a bad odor. Cleaning them cured the odor issue but now the sinks are backing up, and I'm worried I ruined the vaccuum seal or whatever and not sure what to do now.
It’s not called an air admittance valve (AAV); it’s called a trap primer. A trap primer keeps unused traps filled with water so the water in the trap doesn’t have a chance to evaporate.
I have a question , can you tell me why I have sewer flies /knats coming out of my bathtub drain , I've tried every online remedy and had a plumber come out and clean drains , they are still coming and more so now ,last resort going to call pest control but they are telling me.they can't garentee they can get rid of them , do u know how to get rid of these out of the drain ?
I have a P trap what also leads to my washing machine waste pipe, and I've had to unplug the washing machine waste pipe to replace my washing machine and I am sure water from the sink is over flowing in the ptrap and in to my machine waste pipe. Is that normal...
I've noticed the past year the kitchen drains smell horrible. I've done everything. they get used frequently.. I'm almost positive it's sewer gas...the drains are not clogged...and I ONLY smell it coming from the kitchen drains... not anywhere else in the house...It seems to stop if I slowly run cold water through the drain... but for whatever reason, if I turn the water on full, it doesn't help...so I'm always running water slowly for a little bit when I'm finishing up in the kitchen
P trap with cleqnput is amazing I've had one for 10 years in bathroom forcsink and tub saved Ali of work. Few times.
Exlent explanation
Can someone please explain how a block in the vent causes a vacuum and therefore water getting stuck?
so my trap only lets gas through when I run the water. any other time there is no detectable smell. the trap is new and clean and always seems to be full and not dry. I recently used clog remover in case there was anything stuck elsewhere along the line, but the flow is consistent and doesn't indicate a backup Any ideas?
I’m dealing with this same problem did you end up figuring it out?
@@briannamoore315 sort of, i bought a whole new p trap and extensions and cut the arm piece extension to the wall so that there is about 1 inch going into the wall - before, the extensions were uncut and there was about 5 inches going into the wall.
I also cut the sink drain stem to about 1 inch into the extension that the joins the bend/p-trap.
I don't know if there was something about these pieces being too long that enabled the gas to flow up, but it's largely mitigated the smell.
Someone also mention to use 1 1/4 p trap rather than the 1 1/2 as it's a bathroom drain and not a kitchen drain. I'm curious if that would totally eliminate the problem.
give it a try and good luck!
If you have a second home where you go once a year and usually traps evaporate causing uncomfortable situations to your neighbours, what can be the solution?
A little vegetable or olive oil run water to make sure trap is full then add a thin layer. Pour slow and don’t add a lot will help with evaporation
Seal the valves and the drain inlet when you leave. Unseal when you return. Simple adhesive tape should do the job.
Simplest solution I think would be duct tape. Then when you come back to that house you fill up the sink or tub with the tape still on, and then rip the tape off under the water to prevent any gas to come out. Also note that H2S is often present in “sewer air” and can incapacitate or cause serious damage at even 1 part per million.
In my washer line p trap sometimes the water comes up from the top depending on the size of wash. What should I look at
That sounds like you may have a clog or backup down the line somewhere. The water will have no choice but to back up if that happens. I think you need to look for a clog somewhere downstream of your P Trap.
@@LRN2DIY I put a snake in the drain twice 100 ft snake an replace the p trap than it’s still not draining still idk what to do I didn’t mess with the pipe or move it. I can’t get it figured out
@@jroc4314 Sounds pretty serious then. Might be time to get a plumber over there.
@@LRN2DIY ok thtnks
@@jroc4314 What size piping are you using in the drain?
Huh.. really expected more comments about Thomas Crapper
Where do I buy the transparent pipes?
They’re available on Amazon but I wouldn’t recommend them. The reviews all agree that they crack prematurely.
I've owned 6 of them because I assumed I was installing all 6 incorrectly so I kept buying them. Listen to the reviews.
Anyone knows if a cistern pump can actually cause a siphonage?
Do drains in the floor have a p trap ?
1:17, if you turned it around backwards it could also be called a letter "J"
Or just have is as it is and call it a U trap, as we do in Britain
Think we call that a U-bend in Britain
We do indeed
@@ryanjames3130 Makes sense as it is actually shaped like a U and has a bend in it.
As opposed to looking slightly like the letter P once it’s turned upside down and rotated 90° 🤦♂️
Because it looks like U, not a P
I use mine every day and I still get fumes ,PLEASE HELP. I don't know what to do anymore.
Your sponsor links are broken.
Another way you'll know if your P-trap isn't working is that your house will be infested with sewer roaches.
No one else is immature enough to laugh at thomas crapper inventing the u-trap?
I think all of us are. I had to hold myself back while filming. I remember learning about him in school and we all acted our age when we heard his name :)
Yeah BUT, if you catch sight of the DISGUSTING things in that trap, then the transparent "feature" might result in you vomiting upon seeing what's in there (including drowning roaches!!). Some things you DON"T want to know.
I agree. I have a wife and three daughters in the house and the hair situation can be downright disgusting sometimes, when it comes to pulling it from drains. I love them and their hair, just not when it's turned into black slime.
Thomas.......Crapper 😃🤣😂
I cleaned out my p trap whilst changing a part of the sink. My god it was stinky and full of nasty gunk! The Mrs was mad because of the smell 👃 😂
Why don't they make all p traps clear?
Is “crap” named after Thomas Crapper?
I must not be very smart. I am not sure how a gas would not just push its way through the water if there was enough pressure build up. The dead animal scenario may create a vacuum but then the pressure from gas build up has to go somewhere...
THOMAS CRAPPER!!! 🤣
Thomas Crapper you can’t make this shit up. Pun totally intended.
Yeah, he's been the butt of many jokes over the years. Pun also intended.
Thomas Crapper lol....like he was born to improve toilets :D
👍🙂
If you built it the other way and sat on the other side, you wouldn't have to flip the P to make it make sense.
Thomas Crapper.......
That was my takeaway too😅
Jesus. I was like "man this thermal camera section seems a bit shoehorned, is it a sp- Yep, it's a sponsor".
No thanks.
You... didn't pay anything to watch a very informative video, did you?
@@markw4206 What a terrible argument. Imagine being so intellectually bankrupt that you think it's a good point.
@@Asdayasman Imagine just randomly throwing out the phrase "intellectually bankrupt" because you can't refute a basic true fact. You didn't pay for this video. Either you did or you didn't get anything out of the explanation before the sponsor message. If you didn't, move on. If you did, you still didn't pay anything.
Now insult my mother. Maybe that'll work!
@@markw4206 I will admit that I was a bit confused by the thermal camera info as it seemed like a sidebar that was getting off topic before he announced it was a sponsor. However, this video was so informative and helped me with the exact information I was searching for (and more) that I give kudos (and a thumbs up) to the video.
Hi I live in Tijuana Mexico most places apt and hotel don't have that p trap because previous renters will always steal them when they leave to resell them , what can I do or use to stop those fumes when their is no p trap
1st
Did you really just say “bri-an” 💀
Get on with it eliminate your childish quips
Brah, Thomas Crapper.... seriously...
Please pronounce your T's.
Thomas Crapper !! 🤣🤣🤣
🥱 a heat imaging tool. Useless with this topic. Blocked