Over 698,000 strictly plumbing related posts
Plumbing education, information, advice, help and suggestions are provided by some of the most experienced plumbers who wish to "give back" to society. Since 1996 we have been the best online (strictly) PLUMBING advice site. If you have questions about plumbing, toilets, sinks, faucets, drains, sewers, water filters, venting, water heating, showers, pumps, and other strictly PLUMBING related issues then you've come to the right place. Please refrain from asking or discussing legal questions, or pricing, or where to purchase products, or any business issues, or for contractor referrals, or any other questions or issues not specifically related to plumbing. Keep all posts positive and absolutely no advertising. Our site is completely free, without ads or pop-ups and we don't tract you. We absolutely do not sell your personal information. We are made possible by:
Author:
kolevbg (TX)
First thanks to everyone who can help with information from past experience.
Second I've read a good deal of other posts before starting to post myself. I know about p-traps and what they do, vents and what they do and I've already tried the usual chemical through vents, replacing toilet seals, pouring water in sinks etc to no avail.
Not to brag or anything, clearly I am not smart enough to figure it out by myself, but trying to cut the obvious recommendations I've already tried.
It's an office building that's about 10 years old and my office is over where a butcher room previously was, out of an Indian deli.
Next suite has a small commercial kitchen.
When they work in that kitchen we get sewer smell in the office.
There used to be a sink in one corner and there's floor outlet there, but the smell does NOT come from it.
In fact we can't figure out where it comes from.
AC is definitely not it either although it is part of the equation when it works as it moves it around the room.
A local HVAC expert with 40 years on his back smoked the building and there was no smoke anywhere inside. All vents on the roof were puffing steadily and he said if he increases pressure it'll start coming from the sinks.
He smoked from the roof, then from the grease trap, then from the city sewer entrance (or exit, not sure).
Personally I got the impression he knew his stuff.
Alas he couldn't tell me what to do next short of throwing tons of money for test with water, which, he made clear, is not guaranteed to give actual answer to the question if there's a leak under the foundation, but is guaranteed to NOT tell me where it is, if there's one.
Here's what I'm trying to grasp: how is it possible that we get the smell when the kitchen is working, but we didn't get it when they were smoking the system?
Finally, to be honest I am not sure what exactly they do in the kitchen that produces the smell. I assume it has to do with flushing the 3 compartment sink as I've seen them fill it all up while they work, but I've tried filling it myself one weekend and flushed it and that didn't cause anything on our side.
Yet it's definitely the kitchen that makes it happen. Last week they were off and we were odor free and before they moved in we never knew there was a problem for a whole year.
Thanks again!
|
Post Reply
|
Author:
Wheelchair (IL)
Is the a food service area, with 3 sinks, emptying into a grease interceptor?
Best Wishes
|
Post Reply
|
Author:
sum (FL)
I had a similar issue many years ago in an office building. There was an intermittent sewage smell that the building maintenance personnel nor plumber could find. The smell is strongest in the morning. We couldn't find a pattern to it.
Initially the building manager issued a can of Lysol to each employee in the office.
After more complaints and more investigations they finally figured it out.
The central AC unit on our floor on our side of the building was mounted overhead in a maintenance room, above the false ceiling grid. It has a pipe that discharges the condensate water...and someone decided to drain the condensate pipe into the sewer line, not only that, they didn't put a p-trap on the branch of the sewer line that receives the condensate discharge. Sewer gas would escape from that pipe and fill the space above the false ceiling where all the AC ducts are. There is an air return in that maintenance room, and some of the ceiling tiles were missing. When the AC comes on, the return sucks in all the sewer gas and blow them out into the rest of the offices.
They didn't do a smoke test, but if they had done one, the smoke could be filling the space above the false ceiling or behind the wall cavities and may not be obvious.
Edited 1 times.
|
Post Reply
|
Author:
kolevbg (TX)
To sum(FL):
Thank you for sharing this, I hope it helps others, but afraid it won't help in this case.
I think AC is out of the picture for those reasons:
1) The kitchen and the office suite have different AC units; the one in the suite is actually newly installed unit since the suite was built from a formerly larger space, which was separated; the new suite got new AC and all ducting for the suite was assigned to the new AC.
2) All AC units are on the roof; all of them have P-traps on the condensate line; and none uses economizer
3) IF AC was notable part of the problem then smoking would have caused smoke to appear from the vents, wouldn't it?
To wheelchair (IL):
There is a grease trap installed. It's been cleaned since and that doesn't change anything.
To the best of my knowledge the three sinks (and there's a floor sink near them) all go to the grease trap.
It goes through another opening on the floor BTW. That is, the 3 sinks have a pipe underneath them, which leads to an open "sink" in the floor.
My terminology here is a little loose I am afraid. It's a square plastic thing about 12'' side with the pipe in the middle and 4 rubber covers meeting.
The kitchen itself does NOT get bad smell.
Assuming it's the amount of water that causes the pressurizing in the sewer my best chance for reproducing the problem is filling the 3 sinks and emptying them at once, right?
Sometimes they cook less and in such days we can notice gas, but it's not too bad.
Edited 1 times.
|
Post Reply
|
Author:
sum (FL)
May be others would have some suggestions for you what to test next.
As far as "3) IF AC was notable part of the problem then smoking would have caused smoke to appear from the vents, wouldn't it?"
In my case, no. Because the air handler on the office wing on my floor was mounted overhead in the maintenance space, the unit was hung from the framing. There is a condensate drip pan under the unit, and the outlet of that pan is what is connected to an illegal branch line without the p-trap. So I would imagine the smoke would come up through the main 6" sewer vent but not sure how much of it will come through the 1" condensate branch. Once smoke comes out of that drip pan, it will basically fill up the overhead space and I doubt enough of it will get inside the actual ducting connected to the vents.
In any event that's not relevant to your situation. Good luck on finding the culprit.
|
Post Reply
|
Author:
DaveMill (CA)
I'm not a plumber. Some ideas, not trying to be insulting:
1. Is it possible the smell is NOT sewer gas, but natural gas/propane? Do you know what those gasses smell like in your area? Could it be a gas leak somewhere in the kitchen?
2. Have you stood quietly in the corner of the kitchen for 30 minutes, just observing? Watch EVERY activity. They do something when they are cooking that does not happen when they are not cooking that causes the odor. Write everything down: cooking, cleaning, window & door activity, what switches they throw and appliances they use and knobs they turn, everything.
3. What appliances have a water supply or drain or vent or grease trap? Classic odor sources.
Good luck.
|
Post Reply
|
Author:
kolevbg (TX)
Thanks for the suggestions.
I am not expert in smells, but this is not natural gas. One of the gas appliances they brought does not support primer flame on 0 level as it should and leaks a little gas because of which they leave one of the hoods always working...and I think that lets me know how natural gas smells. It even goes through the walls into our area and I can smell it Monday morning when I walk into our office.
But what I call the sewer smell is quite different and the plumber smelled it and called it sewer and I believe him.
So did few of the cooks themselves , who had it on other locations before.
Second, I think you are quite on the spot with being in the kitchen and observing. Only it won;t take 30 minutes and probably more and I think I'll stick a camera and just record them.
Smell starts around 9:30 in the earliest when they start working at 7 AM.
My theory so far is that a pipe is cracked somewhere under the foundation , there's an air gap there and it needs time to pressurize before starting to make its way through the foundation.
Edited 1 times.
|
Post Reply
|
Please note:
- Inappropriate messages or blatant advertising will be deleted. We cannot be held responsible for bad or inadequate advice.
- Plbg.com has no control over external content that may be linked to from messages posted here. Please follow external links with caution.
- Plbg.com is strictly for the exchange of plumbing related advice and NOT to ask about pricing/costs, nor where to find a product (try Google), nor how to operate or promote a business, nor for ethics (law) and the like questions.
- Plbg.com is also not a place to ask radiant heating (try HeatingHelp.com), electrical or even general construction type questions. We are exclusively for plumbing questions.
Search for plumbing parts on our sponsor's site:
Special thanks to our sponsor:
|