Can someone explain what a bell trap is? I have in my older home what I think are metal bell traps. Grate has a bell shaped cup that goes over drain. Is the theory that a small amount of water lays in the drain sealing the bell to drain and sewer smell out, but still allows water to drain off the floor down into drain? The bell and grate cracked on one of mine and I am getting a smell now periodically.

Can you still buy the metal lids (grate cover) or do I have to replace the whole thing with plastic? Can someone please advise me on this?

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Originally Posted by apollo1

Can someone explain what a bell trap is? I have in my older home what I think are metal bell traps. Grate has a bell shaped cup that goes over drain. Is the theory that a small amount of water lays in the drain sealing the bell to drain and sewer smell out, but still allows water to drain off the floor down into drain? The bell and grate cracked on one of mine and I am getting a smell now periodically.

Can you still buy the metal lids (grate cover) or do I have to replace the whole thing with plastic? Can someone please advise me on this?

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Section 2.3 (traps and Interceptors) of The National Plumbing Code states, " (4) A bell trap shall not be installed in a drainage system.

Remove the bell trap and replace it with a regular trapped floor drain.
You are leaking sewer gtas into your home. Sewer gas is hazardous to your families health and the methane content in sewer gas is explosive.
Replace the bell trap or seal it off at once.

First things first.I have a main trap about 20 feet from the house between the house and the city sewage line as described below. That keeps me isolated from the fumes from the main city line right?

Here's how it goes... Two upstairs bathrooms have comman drain to outside the house. Upstairs kitchen sink and basement stationary tub(washer)and basement floor drains share another line exiting the house. 2 lines total exiting the house. These two lines tie in together just outside the house it then travels down to the main trap in the yard and continue to main sewage line.


I think the smell is mainly decaying food from garbage disposal on kitchen sink that is laying in floor drain lines in basement. Once I wash clothes and the basement drain line is flushed well smell is gone.
Now...
When you say replace the 2 bell traps with a 2 regular trapped drains I'm assuming you are saying to bust up the concrete and replumb the whole whole basement? A lot OF WORK!

Shouldn't a bell trap be fine as long as there is water in it? I didn't have this problem before the lid cracked.Can I still get a metal bell trap lid?

Is there another way without busting up the floor? Another thing my main line exiting my house may not be low enough below the finished concrete slab to install flloor traps.

Tom knows what he is talking about. It sounds like bell traps were a bad idea that went away. It is hard to find parts for old stuff that worked well, let alone something condemned by modern codes. No doubt in my mind you would be better off taking his advice. Don't worry about the height of a trap. You should be able to dig down as far as you need to, and then come back up to where ever the drain is. You may want to rent a masonry saw to limit the area broken up. Or concrete is cheap even if the easy to use Sackrete or other brand premixed stuff. Pour Roc is even easier to use, but more expensive.

You may need help from Tom in connecting modern fittings to old cast iron drains.

"First things first.I have a main trap about 20 feet from the house between the house and the city sewage line as described below. That keeps me isolated from the fumes from the main city line right?"
Perhaps that running trap in your sewer line isolates you from the street main but you still have a open line to the sewerage in your home and in the house main which leaves you in the same situation as if the trap wasn't there. The fumes are just a hazardous to your family. I can not find you a repair part for your bell trap drain however I can give you a link where you can replace it

http://www.rhinounit.com/IPScorp/wt_...elltrpdrn.html

I would still recommend installing a regular cast iron floor drain. You would only have to break cement around the drain abd connecting drain pipe and you'd have to do that any way if you replaced with a bell trap drain.

"Another thing my main line exiting my house may not be low enough below the finished concrete slab to install flloor traps."

A regular floor drain won't eat up as much elevation as your bell trap, and I didn't say change out all the bell trap drains. Just the one that's broke and leaking sewer gas. Good luck, Tom

You have described the theory behind the trap seal correctly. Replacement caps are available but rare.

I have had to order one from my local hardware store for my 9" x 9" cast iron bell trap floor drain (in our basement)whose cap is missing and the sewer gas continues to pour in. The cap is supported at its rim and the cap "cups" over the drain pipe while the edge of the cup fits in a "moat" surrounding the drain pipe. This is what constitutes the water trap allowing water entering through the perforated cap rim and flowing through the "moat" and up over the edge of the drain pipe (like a weir).

Good Luck.

Most of the manufacturers for these metal grates and drain lid covers are no longer in business or don't manufacture the same style any longer but Yes you can still buy metal grates and lids for almost any size bell trap through Deasey Machine. They custom make almost any size for shower drain covers, and bell trap drain covers. They also make them in steel, and stainless steel. Check there website: www.deaseymachine.com
The cost may be a little higher but it may keep you from cutting your floor out to replace the bell trap!
Hope this helps.

You responded to a 5 years old thread am sure it is closed by now, Thanks.

John

But the information is still useful to others who are reading these threads for answers. Thanks Sdizzy!

But JAnder if we put up all 7 year old dead threads we would have no room for new traffic, Yes you can go back and access them but all those old threads just clutter up the page, Tom