Can a toilet cause this much trouble?

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  #41  
Old 07-28-14, 09:38 AM
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czizzi,

Doing what you suggested........running the a/c line to the emergency line and directly outside the house has been suggested by both the plumber and the a/c guy. The plumber suggested capping of the sewer line when the rag experiment worked, but the a/c guy said we'd run the risk of Legionaire's (sp?) Disease.

I don't have a problem with them rerouting it, but I want to be sure we're not correcting a problem while ignoring the cause. I need explanations based on something that can be proven, and your explanations czizzi, are the best I've heard so far.

The a/c guy said last week that his guess was that somehow water was getting drained from the p trap, but he didn't know how. Your explanation answers that.

I don't know what my husband was looking at, but I was on the phone wieth the roofer today, and we don't have any ridge vents at all! They're going to come out later this week and give us an estimate on installing some.

The only other thing that was done to this house from a ventilation perspective before we bought it is that one of the two attic fans was replaced. We asked for both to be replaced before we closed on the house. I'm not sure why they weren't.

Could the attic fan now working explain why the lady who lived here before never had this problem? They may have never worked the whole time she lived here.

I really need an explanation about why this problem happened just "all of a sudden".
 
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  #42  
Old 07-28-14, 10:05 AM
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czizzi, I agree the testing has raised questions, but there are details we don't have. For the house to be negatively pressurizes it would need to have been built very tight, few are and we don't have a test result to verify. Next, we would need an extreme amount of leakage on the return side, which is possible and common. Next, I'm assuming the condensate drain is in the attic which isolates it to a major degree from pressures inside a house.

As for the new ridge vent and possible blocking of the soffit vents, they could be contributing as well as a leaky return in the attic. But many attics suffer from imbalanced ventilation and leaks in return and neither or both should be able to draw air through the drain. However, if both ridge and soffit venting are blocked it could create much larger pressures. Natural air temperature differences would not pull through a working trap.

Note, that a new roof and blown in insulation have indeed resulted in a ridge vent that was not cur open and blocked soffits. Both conditions should be visible from the attic. There should be baffles in each rafter bay and an obvious cut back at the ridge.

I noted you mentioned a trap on the condensate line, that would help if it is there and functioning. Note, it does not help in the winter and needs something added each fall.

Bud
 
  #43  
Old 07-28-14, 10:15 AM
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Donna, I'm slow at posting so didn't see yours until mine went up. You mentioned an attic fan: "Could the attic fan now working explain why the lady who lived here before never had this problem? They may have never worked the whole time she lived here."
Is this fan part of the ac unit or are they attic exhaust fans?

If attic exhaust fans, they could be contributing to the problem. But, when running they should be exhausting everything (even air from the house) to the outside. But they could be strong enough to empty the trap!!

Are these fans attic exhaust fans?

Bud
 
  #44  
Old 07-28-14, 12:34 PM
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Bud,

We have one attic exhaust fan that works. We don't actually have a ridge vent. I spoke to the guy
this morning who installed the new attic fan motor. He said that it would take a pretty powerful attic fan to be responsible for negative pressure in the house.

I'm not saying you're wrong about the fan being strong enough to empty the trap, but I really think our a/c guy would have thought something of it when he saw it if that was the case.

Interestingly, when I told the attic fan guy about the negative pressure theory and mentioned that we were considering everything that had been done to the house just before we moved in, he mentioned insulation blocking the soffits.

Hopefully when the insulation company comes out later this week to blow out our soffits with their machine that blows in the insulation, that will help. The owner did say he had never heard of someone having this problem before.
 
  #45  
Old 07-28-14, 01:08 PM
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-Attic fan pulling air mechanically out of the attic.
-No Ventilation at soffit to replace air removed mechanically by attic fan.
-Certainly creates a pressure differential that pulls air from the house proper if soffit unavailable.
-Attic sealed from house, so neg pressure needs to be satified somehow.
-Condensate Drain is on the up stream side of the suction of the squirrel cage in the air handler and therefore under a neg pressure to begin with.
-Sounds like a negative pressure situation to me.
-Condensate directly tied into sewer line at bathroom.
-Sucking at negative pressure will increase the demand for air at the handler and thus the condensate drain.

My logic won't let me go any further, but we will continue to monitor your feedback as you meet with the various contractors involved.
 
  #46  
Old 07-28-14, 03:23 PM
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czizzi, I haven't been able to sort it all out either, but I do agree you are on the right path.

How significant is the trap used to block the condensate drain? It must be a smaller line than a sink drain and then perhaps a smaller trap. What is important is the height of water in the trap. Your suggestion to bypass that drain should be next on the list and Donna, from now on note if the attic fan is or has been running. You might even turn it off for awhile.

My other concern is the actual point where that drain attaches to the vent stack, is that well sealed or leaky.

Bud
 
  #47  
Old 07-28-14, 04:25 PM
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Czizzi,

So other than rerouting the line, what can we do about it? What I mean is.....what can/should we do in addition? What will alleviate negative pressure? Our a/c guy is working on what he might be able to do.

Should we just not get ridge vents installed? Would that just compound the problem?

Our plumber just left from reinstalling the toilet. We told him about the bloop, bloop, bloop sound. He said that when he was here Friday, the 3/4" line going into the P trap was holding water and making a gurgling noise.

He wedged a piece of wood underneath holding the 3/4" line at the duct work. He said the 3/4" line needs to be slanted downhill so the water can drown out.

I guess what he did Friday is why I started hearing the "bloop, bloop, bloop" on Saturday.

One other thing that I think I have forgotten to mention is that Friday when the plumber was here, he ran his camera through a small hall in the master bedroom closet. It's on the other side of the sink in the master bathroom. Through the few holes the plumber had made, we could feel air conditioning. It was cooler in the wall than in the closet!

Our a/c guy is on the way here now. I'll report back after he leaves.
 
  #48  
Old 07-28-14, 07:08 PM
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Okay. Our a/c guy left about an hour ago.

He checked things thoroughly, and he believes we have two problems.

1) He thinks we have a cracked pipe somewhere, but he has no idea where.
2) We have a negative pressure problem, but he has no idea why.

He's been in the business 41 years, and he's one of the best. We've known him 20+ years, and we trust him implicitly.

He thinks we should have someone do a smoke test. I called the Waterworks today, but they don't do it. I'm going to call the city tomorrow and see if they do it.

Our guy said we don't want ridge vents AND attic fans, so we'll just stick with what we've got.

We mentioned to him some of the suggestions from here on the forum.

We talked about rerouting the a/c drain line, but because there was one time we had the rag on and still had stink, he said that wouldn't fix it.
 
  #49  
Old 07-28-14, 07:55 PM
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Your grasping at straws here... " Sorry late to the party" LOL

I read this thread through some.. Listen. Any gloop gloop glopp sound it a vent issue. Either a wet vent somewhere or air handler/ attic fan induced..

But traps in the home are designed to support a -/+ 1 pressure difference..

You need to smoke bomb the sewer system with all traps filled... Then you need to start running items like attic fans, air handlers and such systematically...

If the fans and air handlers do not turn up anything then you need to start using fixtures one at a time... Probably one fixture is not plumbed right and sucking water from another trap..

Common is the dual sinks you mention... Often a double fixture fitting is not used and uneducated plumbers install a double sanitary tee instead...

Just my two cents...

Its very simple IMO to find the issue...
 
  #50  
Old 07-28-14, 08:26 PM
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Would ya'll agree that if there was a broken or leaking pipe, then the smell would be continuous? That is why the plumber thinks there's not a leak. He said the smell would be continuous.


***by the way.....The bloop bloop bloop sound stopped. The a/c guy removed the piece of wood put in place by the plumbing guy, and it stopped. It's funny to me to see service guys disagree. :-)
 

Last edited by Donna J; 07-28-14 at 08:46 PM.
  #51  
Old 07-28-14, 08:51 PM
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Would ya'll agree that if there was a broken or leaking pipe, then the smell would be continuous?
No, not IMO... You could have a cracked pipe and sewer gas may only be drawn out from say an air handler...

Let me ask you... what pipe material is in the home??? Cast? PVC? Copper?

Also a note, often tiled showers produce a smell. And more then not because the length of the drain to the trap. Many homeowners put a type of drain cleaner down there and the stand pipe to the trap is so long that the bacteria in the pipe manifests itself.. But only when drawn out from an air handler... Its that section of pipe from the shower drain to trap.. And because of the drain cleaner reaction... ( Like rotton eggs)

Dont know what you have there..

Probably if you took pics of your home layout plumbing wise we can uncover some things that may be the cause...



Again we are only assuming is all and the smoke bomb and systematic testing is the only way...
 
  #52  
Old 07-28-14, 09:25 PM
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We have PVC pipes. We've duct taped every drain in the bathroom before. I don't remember which thread that was in. The stink was still present with every drain and the sink overflow drains taped.

I mean no disrespect lawrosa, but I think I've covered what you're asking in other posts. Please forgive me if I don't answer something I've answered in another post.
 
  #53  
Old 07-28-14, 09:37 PM
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but I think I've covered what you're asking in other posts.

Other posts here or other posts from your many other threads???


Its not rocket science IMO... I would have found the issue already and any competent plumber would had too..

Possibly you are using guys working under a master plumbers license... Some have no clue and are probably gouging you on service call charges...

Like I said... Smoke bomb and someone competent....

I cannot offer any other advice.... Everyone is just guessing that you had out so far..

And sry I did not read all the posts thoroughly, but I been there done that already........
 
  #54  
Old 07-29-14, 03:06 AM
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I just had to defend the honor of my plumber here even though you don't know him.

Over the last 5 weeks, our plumber has been to our house at least 7 times. He has talked us through investigative steps we could take ourselves to save money by phone and answered questions by phone at least 25 times, but probably more. There have been a few e-mails as well.

A few of these visits have been nights and weekends. We served he and his crew pizza Friday night because they didn't leave our house until after 8 pm. They had been there for 3 hours.

He has performed a peppermint test, corrected another plumber's mistake, and replaced the wax ring on our toilet.

He has been respectful of our sheetrock, making holes as small as possible to run his camera through. He has told us that if it were his house, he would have already cut into the sheetrock and started replacing things, but he has respected our desire to not have that happen at our house until an exact location can be pinpointed.

We have paid our plumber a whopping $350.00.

He's a man of integrity, and I'll not have anyone make even the slightest unfounded accusation against him without defending him. :-)
 
  #55  
Old 07-29-14, 07:44 AM
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Possibly you are using guys working under a master plumbers license.
He's a man of integrity, and I'll not have anyone make even the slightest unfounded accusation against him without defending him. :-)

I said Possibly.. Not that you were or were not.. Possibly you read it wrong and have misunderstood me...
 
  #56  
Old 07-29-14, 08:37 AM
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Hi Donna, I sympathize with your frustrations and it is difficult on our end as well, especially as these threads get very long. A couple of posts back you said "Would ya'll agree that if there was a broken or leaking pipe, then the smell would be continuous? That is why the plumber thinks there's not a leak. He said the smell would be continuous."

First, the stink should be exiting the top of the vent pipes ONLY. Unless the path of the smell is from above the roof to inside your house somehow (unlikely) then there is a hole. Whether that is a broken pipe, poor connection or sewer gas being drawn back through the condensate drain is to be determined.

"Would the smell be continuous" not necessarily as houses experience a constant flow of natural convection in and out. This air flow varies with temperature, wind, and internal appliances and air movement only occurs when there are pressure differences. Your testing has indicated that air pressures do affect the presence of the small.

Opinions on the internet in regards to draining into a vent pipe, I'm not an HVAC guy, vary from being against code to just being a bad practice and even if that drain line has a trap it can go dry during the heating season. An emergency drain was suggested so it should be installed and the current drain sealed, at least during these diagnostics.

Once that is sealed, if the smell continues there is another opening where it shouldn't be. Finding a water leak is much easier than finding an air leak, but you have at least narrowed this down to one bathroom.

Apologies if I'm falling behind, it is a busy time of the year. Let us know if the above is possible.

Bud
 
  #57  
Old 07-30-14, 07:32 PM
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I wanted to let ya'll know, that after talking with a gentleman in Canada yesterday who wrote an article about negative pressure not allowing a house to vent properly, we cut off our attic fan, and the stink stopped immediately. The air blowing behind the wall stopped immediately. I know it may sound crazy, but I felt a difference in my body when my husband hit that breaker switch.


After 24 hours of being stink free.......the first time we've had that since we moved here 6 weeks ago...... we had a little sewer smell when we ran the clothes dryer. As soon as the dryer stopped, the stink was gone.

All of this time we've been searching for what we were doing differently than the lady who lived here before.

Here is what we now believe happened:

*On June 9th, the attic fan motor was replaced, so it began working properly.
*The children of the lady who lived here continued to remove her belongings and met various repairmen here and smelled nothing because there was no problem.
* On June 19th, the insulation company blew 6" of insulation in the attic. Our attic has NO baffles, so we believe the insulation could not help but have gotten into the soffits. The house became unable to breathe at this point.

* The next day, on June 20th, we encountered a house that reeked of sewage.

Next week, the insulation company is bringing a crew out to get in the attic and blow out every soffit on our house.
After they've finished, we will try the attic fan again.

I'll report back next week for those who are interested in how this turns out.
 
  #58  
Old 07-31-14, 12:21 AM
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I have not responded to Donna's multiple threads on this issue for ten days. My last post, also the last post in the thread (http://www.doityourself.com/forum/to...ml#post2299517) was ignored. The connections between stink, A/C operation, attic fans, little ventilation in the attic and perceived "open" sewer pipes in the attic are NOT coincidental.
 
  #59  
Old 07-31-14, 02:45 AM
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Donna, unless the insulation guys install baffles, your attic fan will blow insulation right back into the soffits. Just so you are aware.
 
  #60  
Old 07-31-14, 05:06 AM
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Donna, in post #46 I stated "You might even turn it off for awhile." in reference to your attic fan. But the fan and all of the ventilation issues you mentioned are only half of the problem. If there were no "hole", condensate drain or disconnected vent pipe, there could be no smell. You should still determine where the "hole" is and have it fixed, sewer gas is not supposed to be able to enter your home.

As for the venting/insulation problem, as Chandler stated, you should have baffles installed and you need to be sure a ridge vent is in place and functioning. As for using an attic exhaust fan to cool the attic I have attached a link to explain.
Fans in the Attic: Do They Help or Do They Hurt? | GreenBuildingAdvisor.com

Glad you are making progress, but don't stop until you identify where that smell is coming from. The condensate drain is suspect, except it vents into the attic. I'm concerned at how much smell is actually entering the house and thus possibly a larger hole is located closer to that bathroom.

Bud
 
  #61  
Old 07-31-14, 05:26 AM
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Thanks Chandler. I will tell my husband what you said. Is this a difficult and/or expensive project? Are you sure the attic fan will blow the insulation? I believe it pulls the air out of the attic.

Furd, I'm sorry. I didn't mean to ignore your post. This has been the longest, most trying process we've ever gone through, and as you can tell, my knowledge of plumbing.........while it has increased.........is still quite limited.
I may not have adequately described the plumbing in the attic. My husband has seen it, but I have not.

Neither the plumber, nor the a/c guy thinks the configuration is unusual, and no one has ever had a problem in this house before.

If I wasn't such a technological doofus, I could post a picture, but I don't even own a smartphone and my computer is dead. I could take a picture with my tablet and e-mail it to myself, but then I would have no idea how to post an e-mail to this forum.

Again, my apologies Furd.
 
  #62  
Old 07-31-14, 05:42 AM
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  #63  
Old 07-31-14, 06:11 AM
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Thanks Lawrosa. If my husband is willing to go in the attic later today, I will see if we can get a good picture. I think I can follow those instructions.
 
  #64  
Old 07-31-14, 03:38 PM
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Guys, my husband got in the attic and discovered that the attic light is on the same breaker switch as the attic fan, so he couldn't take a picture. IF we still have a problem after the insulation is removed from our soffits, (which we aren't anticipating), we'll cut the attic fan breaker back on long enough to take a picture.
 
  #65  
Old 08-01-14, 03:56 AM
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Hi Donna, A curious question, are both of those attic fans installed to exhaust air, or was the one that is not working positioned as an intake fan? One intake and one exhaust would have canceled the majority of the pressure difference.

Bud
 
  #66  
Old 08-10-14, 06:48 PM
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I wanted to be 100% sure before I posted this, and I am, so here goes.

The stink has stopped. Praise the Lord!!!!!!!!

I believe I have fully prepared myself for the onslaught of "I told you so" responses I may be about to receive.

Early on in this process, I spoke to a retired plumber with 60 years of experience. I called him back this week to talk to him about negative pressure. He said he wanted to come take a look at our situation with his son.

They came out Wednesday and stayed about an hour. The stink wasn't "active", and they couldn't figure out what the problem was.

Wednesday night the older gentleman called back and asked if they could come back the next day.

They came back Thursday, and after they had been here about an hour, the stink started stinkin'.

The plumber's son had something "click" (we know it was the knowledge from God we'd been praying for), and he said he thought the bathroom had been remodeled.

He said he thought the place where a pre-fab cabinet now stands.........that goes from 1 foot below the ceiling to the floor.....used to be the shower. We concurred, because there was a light fixture above the cabinet. (That you can't even change the bulb in by the way.) I should probably note here that the pre-fab cabinet is not as deep as the shower was, so there is a good bit of dead space between the back of the cabinet and the wall.

He asked if he could drill a hole in the back of the cabinet at the very bottom of it.

I told him that as fed up as I was, he could kick in the back panel of the cabinet for all I cared!

He cut out a small hole and ran a camera through it. The first thing he said was, "I see a bag." I said, "It must be a bag of poop!" :-)

He then said that saw an open drain where the shower had been. We flushed the toilet, and air came up through that drain.

He capped it off, and we haven"t had a smell since. Praise the Lord!!! For the the last 80 hours we've been able to enjoy our home in a way we haven't been able to since we bought it 7 weeks ago.

I want to thank all of you who made suggestions and tried to help us. We appreciate you.....well, most of you. ;-) Just kidding!!

I just have 2 more questions:

1) Why could my husband and everyone who went in the attic smell the sewage smell up there?
2) Why did the stink stop when we'd shut the bathroom door, cut off the attic fan, or open a window at the opposite end of the house? Could that open drain have been causing negative pressure or a situation that mimicked negative pressure?

Thanks again!

donna
 
  #67  
Old 08-10-14, 09:37 PM
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Bud, I just now saw your question. I have no idea what the answer is, but because of my negative pressure question, I'd like to know.

Thanks.
 
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Old 08-11-14, 06:52 AM
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It is a case where one fan is already too much, so why did they install two? Read the link in post #60 about attic fans, they are basically not good. But having one blow air in while the other blows air out should at least partially balance the air flow.

As for identifying which direction they are moving air, most fans have an arrow on them identifying flow direction and most are installed for exhaust. If one was installed for intake it should be easy to see the difference in how it was installed.

Easy as long as getting into the attic is easy .

Bud
 
  #69  
Old 08-26-14, 07:06 AM
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Bud, I'm sorry to just now be answering this.

Both attic fans remove air from the attic.

I wanted to say too, that the rattle of the fireplace glass doors that I thought was air coming down the fireplace, I believe is actually being caused by vibrations from the air conditioning return unit located on the other side of the fireplace.

One thing still on my mind about all of this is the test that czizzi had me do that stopped the stink before we got that drain plugged.

When we opened a window at the opposite corner of the house, the stink stopped. Closing it brought the stink back.

Cutting the attic fan off stopped the stink unless I ran the clothes dryer.


If it's not a negative pressure problem, what would be the explanation for this? I just want to be sure we don't have a negative pressure problem lurking and hidden now that the stink is gone.
 
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Old 08-26-14, 07:49 AM
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Hi Donna,
First, both fans in exhaust mode (2 is worse than one) is an extreme overkill which puts the attic into a vary negative condition. Air leaks from attic to house will then shift the house pressure in the negative direction. Note I said shift as the entire house will normally have a positive pressure (with reference to outside) at the ceiling and a negative pressure near the floor, called stack effect. Somewhere in the middle is a neutral zone where inside and outside pressures are the same.

When exhaust fans are turned on the pressures inside the home shift, less positive at the ceiling and more negative near the floor. If the house is very air tight these shifts will be more extreme, but I doubt your home would test that tight. However, with the tests you conducted where the added exhaust from the attic fan or just opening a window apparently shifted the pressures enough to reduce or nullify the pressures that were forcing the stink into the house.

It gets complicated tracking the house pressures between summer and winter, wind conditions, and the effect of exhaust fans, but it is normal and that is why drain systems need traps to prevent sewer gasses from being drawn into our homes from any combination of inside to outside pressures.

To give you some numbers, if you put a straw in a glass of water and gently suck and lift the water just one inch up the straw, that is about 250 Pascals, big number very small pressure. House stack effect typically varies between zero and 8 pascals. Your single attic fan can probably pull that attic down to somewhere in the range of -20 pascals, but varies based upon the amount of vent area.

Natural negative pressures are rarely a problem (an open wood fireplace being one exception). Fan generated pressures are often a problem, see link in post #60.

Traps in ALL drain lines will protect you from the stink and other sewer gasses.

I hope this helps but I can add more if you have a specific concern.

Bud
 
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Old 08-26-14, 08:23 AM
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Adding to what Bud has said, plugged or inadequate soffit vents will cause the attic fans to generate more negative pressure. I would be in favor of first: be sure the soffit vents are open to the attic, second: probably add soffit vents to increase the flow, third: add ridge vent and turn off the attic vent fans.
 
  #72  
Old 08-26-14, 09:18 AM
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This was so long ago that you may not remember, but only one of our attic fans works, and only one has worked the whole time we've lived here.
 
  #73  
Old 08-26-14, 11:24 AM
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@ Donna: "This was so long ago that you may not remember, but only one of our attic fans works, and only one has worked the whole time we've lived here."
I do remember and maybe should have been more specific.

If you read the article I referenced you will see that ANY attic fan is a problem. Their perceived function is a quick fix for low insulation and a lack of air sealing between house and attic at the expense of the electricity they use and the conditioned air they pull out of the house. In your case the fan was also sucking sewer gas in through an open vent pipe. Of course that wouldn't have been a problem if the pipe had not been left open.

May people use attic fans, but there are other steps that need to be taken to minimize their bad side. Air sealing between house and attic is a number one energy efficiency improvement (24/7/365) . It will also reduce the amount of conditioned air the fan sucks out of the house.

With your ac unit up there, all ducts need to be sealed and insulated, followed by a leakage test for ducts outside the conditioned space.

Did you have a specific concern regarding the negative pressure?

Bud
 
  #74  
Old 08-26-14, 09:31 PM
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Bud, czizzi brought up the theory of a negative pressure problem when we cracked a window on the opposite side of the house, and the smelled stop. At that time, I read about the consequences of negative pressure, and it included things like carbon monoxide poisoning.

I'd like to sure we don't have a negative pressure problem, so I'm looking for another explanation for what happened with the cracked window experiment.

Also, I'd like to understand how the sewer gas smell got into our attic from an unplugged shower drain in the master bath. I don't know for sure that the shower's faucet was removed because that area is covered up by a cabinet now, but if there's an opening where a faucet was, would that be enough to allow the smell in the attic? I know this has nothing to do with negative pressure. I'd just like to know. Thank you!
 
  #75  
Old 08-27-14, 07:07 AM
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Low levels of positive and negative will always be there, just like gravity. It is the difference in the weight of warm air vs cold air, inside vs outside the house. Then there are higher levels of pressure caused by exhaust fans, ac blowers, dryers, central vacuums, window fans, range hoods, and maybe a few I missed. The problems occur when a naturally drafted appliance encounters a stronger negative pressure than the exhaust gasses can overcome. The solution is to eliminate the older naturally drafted appliances, water heaters, furnaces, wood stoves and fireplaces. If those cannot be eliminated then you need to have someone come in and test those pressures to identify any backdrafting potentials. That is part of what I do.

Then there are the sewer gas issues you have encountered. Those issues are not addressed by chasing down the source of any negative pressures. They are supposed to have been resolved by following plumbing codes which will protect you under all conditions.

If you suspect another open sewer vent, you will need to track that down. The smoke test you mentioned earlier is a good start.

As for the sewer smell in the attic, there are two possibilities in your case. One is a difference in pressure between house and attic under those particular days that moved the small from house into the attic. The other, and I'm not sure where the discussion ended, is the condensation drain into an open sewer vent. As I recall they removed the trap and if so, IMO, that is wrong regardless.

As for opening a window and affecting the source of the smell, it just shifted the pressures as the window either allowed air out or in. I can't be more specific as there were not enough details.

Bud
 
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