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Plumbing in the Home/sewer vent inside the house


We recently discovered a sewer vent inside our house. It was hidden behind a built-in ice maker in our game room. There has always been a smell in the room, sometimes worse than others. When I pulled the freezer out today I discovered the vent. I read in a recent article from your site it is unsafe to cap a sewer vent. What are our options for fixing this problem?


Typical AAV Aplication
Typical AAV Aplication  
You have not given me much information so to answer I have to assume that you are talking about a vent pipe that was installed to serve the ice-machine. I will also assume that there is a fitting on top of the vent and that is most likely an AAV (Air Admittance Valve). This is a valve that allows air into the sewer system but is supposed to keep any sewer gas from escaping. In that it is a mechanical device there is certainly no reason to think it cannot fail and that is the reason most jurisdictions do not allow them. However they are handy in certain situations but if you are unaware they exist they can be a bit of a problem. I think that is most likely your problem and you should just replace the valve. They are not very expensive but if it is threaded be sure to use a good thread lubricant/sealer so the gas does not escape around the fittings threads...This fitting would explain why you mentioned capping the vent and for the record there should never be any reason to cap a regular vent (that being one that extends above the roof and is open to the atmosphere in an approved location) but while this AAV may look like a cap I suspect it is just mistaken indentity...
If this is not your situation you can get back to me but please give me all the details including where you live and the type of building etc...
good luck, cort

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Cortez (cort) Cate


PLEASE read this entire introduction. I have been doing this for a long time and I have come to the conclusion that if you are not willing to take the time to write a detailed question then don't expect a detailed solution! I am getting far to many questions that do not give enough detail to warrant a good solution. I realize it is a little difficult to formulate a good question but if you want a good answer you have to give me good this entire introduction please....remember this website is world wide I have no clue where you live if you don't tell give more detail on the fixture you are having problems with...a one piece eljer 3.5 gallon flush will be totally different than a one-gallon flush toto.....details are important. I can answer most questions related to residential and commercial plumbing for many buildings. I have sufficient knowledge of the UPC and UMC. I will speculate for you if necessary. In those cases I will try to give you some guidance and you should use that to refine the question further and we, together, can seek the answer via a follow up. Plumbing codes and practices vary around the world--If you don't tell me where you live the answer I give may not fit your locality. I am giving my time to you as a way of fulfilling my perceived obligation to share. I am here to try to help you find a solution to your problem. REMEMBER, If you want a good answer you need to ask a detailed question and include where you live, type of pipes, type of building, water pressure if it is a water problem, type of heater, age of appliance & building all these and many more are variables that have an effect on various situations. Detailed information will help produce a better answer.


Since 1972 a California licensed B-1 General Building Contractor, C-36 Plumbing and C-16 Fire Sprinkler Contractor; also installing and servicing Heating, Air Conditioning and Sheet Metal operating as C and C Building and Plumbing, California State License 279516. In 1995 I downsized the company to become semi-retired. Still I remain active in the construction industry. As head of a company I placed personnel and job safety as the number one objective followed closely by training and continuing education. Always seeking to stay informed of leading edge technology in the industry. Also I have spent several years as an Apprenticeship Instructor in the Pipe Trades Unions. Additionally I am a certified OSHA instructor.

United Association of Plumbers and Steamfitters Instruction Training, Ann Arbor, MI Bakersfield College, Bakersfield CA Cal Poly San Luis Obispo, San Luis Obispo, CA Foothill College, Los Altos, CA California Licensed Contractor from 1971

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