Clogged kitchen sink, plumber's nightmare underneath

[achutch]

Here are a few photos worthy of the Plumbing Hall of Shame. This is original construction underneath my kitchen sink.

The original disposer was a Badger 5 and was replaced by a professional back in 1997 after the grinder rusted and allowed big chunks of crap to clog the drain. (I opened the plug on the trap and pulled the stuff out manually -- at least the clog was easy to reach).

Over the last couple of days, the drain became slow and today it plugged. The plunger was nearly useless because of a third pipe that connects upstairs to the boiler pan. Even though I was plunging and pulling back sharply, I'm sure I was sending water up that third pipe rather than directing it toward the clog, wherever it was. Finally got it moving somewhat, waited for the sink to drain, then poured a big kettle of boiling water down it. It all went down. Thinking that the drain was clear, I filled up both sides of the sink and then pulled both plugs at one. The sink backed up again to about where it was after attempting to plunge it, draining very slowly. My last attempt before reaching for the phone was to block one end of the sink with the plunger and turn on the disposer. The disposer pulled down all the water, and apparently provided the force needed to clear the drain. It has recovered for now, but we'll be watching it.

The work under the sink was done by a local plumbing company (still in business today) back in 1986. All 76 units like mine are configured similarly underneath. Note the loops in the copper lines that connect the hot water to the dishwasher (right) and the cold to the outside faucet (left). You can see the drain from the boiler coming out of the outside wall and joining the kitchen drain. I don't know who came up with the idea of running the boiler drain underneath a kitchen sink, but I think there should have been a better way.

By the way, we never pour grease down the sink. We do use the disposer frequently, and the dishwasher runs a full load almost every day.

achutch

[cacher_chick]

I would remove the drain piping from under the sink and clean it all out. If it was clear, I would then snake the line going into the wall.

I would also be suspicious of the condition of the disposer. If it has been used regularly for 10 years, it is likely not sufficiently grinding up the particles which is adding to the problem.

[achutch]

I would remove the drain piping from under the sink and clean it all out. If it was clear, I would then snake the line going into the wall.

I would also be suspicious of the condition of the disposer. If it has been used regularly for 10 years, it is likely not sufficiently grinding up the particles which is adding to the problem.

Good point you made about the age of the disposer. It's about 14 years old and used every day. This one has a stainless steel grinder, but like anything else, it's probably worn out.

This condo was under construction when I bought it. I was able to see where the pipes and vents are in the walls. That drain in the wall immediately becomes 2-inch PVC, turns to the right, and then drops down behind the dishwasher to cast iron and goes down through the slab. My guess is that the cast iron goes from that point about 10 feet before it hits the main (which services 8 units). There have been people living in this complex who have had to have the kitchen drain snaked all the way to the main.

I wish there was some way that mess under the sink could be fixed. But I wouldn't dare touch it myself.

Thanks for the response.

[geniescience]

3rd pipe to the boiler pan upstairs is a problem, as you mentioned, when you plunge.
Can you describe it in greater detail? The end at the boiler pan.

My view is that this can be reconfigured and in a way to make it all plunge-able.

From your description of the "drain in the wall" it sound like your 2-inch trap arm "... turns to the right, and then drops down ..."
This also needs to be looked at or described in greater detail.
The reason why it need looking at is that a trap arm is horizontal between the P trap and the stack.
(Horizontal with the minor slope of 1/4" per foot).
This may be significant.
Can you say more about it?

[cacher_chick]

In my opinion, undersink plumbing in a kitchen that works for 10-15 years without needing to be serviced is doing pretty good.

Replacing the disposer and cleaning out the trap and lines might get you another 10-15 years.
I don't believe in trying to fix something that isn't broken.

[achutch]

3rd pipe to the boiler pan upstairs is a problem, as you mentioned, when you plunge.
Can you describe it in greater detail? The end at the boiler pan.

My view is that this can be reconfigured and in a way to make it all plunge-able.

From your description of the "drain in the wall" it sound like your 2-inch trap arm "... turns to the right, and then drops down ..."
This also needs to be looked at or described in greater detail.
The reason why it need looking at is that a trap arm is horizontal between the P trap and the stack.
(Horizontal with the minor slope of 1/4" per foot).
This may be significant.
Can you say more about it?

The bathroom upstairs is long; let's say two bath tubs long. At the near to the hall end of the bathroom is a double closet which contains the boiler and a 40 gallon water heater each set in a metal pan. The drain is in the front right corner, dropping down to 1 1/2 inch PVC which leads to the kitchen sink. Maybe one of those rubber test plugs might fit there in case the sink needs to be plunged again... never thought about that until now.

The 2-inch horizontal line from the sink runs to the right about 3 feet, then tees down to more two inch PVC and then cast iron. The vent portion of the tee is reduced to 1 1/2 inches.

Corners were cut in these units in many areas. Other homeowners have trouble with their kitchen drains as well.

Maybe I should post a couple more photos. But that will have to wait until tomorrow, as I'm about ready to head to work.

Thanks for the response.

02-28-2011: Added photos of condo floor plan with plumbing lines drawn in. Also a shot of the boiler pan drain, and from a photo taken for insurance purposes (cracked pipe), the second floor pipes including the line from the boiler pan.

[achutch]

In my opinion, undersink plumbing in a kitchen that works for 10-15 years without needing to be serviced is doing pretty good.

Replacing the disposer and cleaning out the trap and lines might get you another 10-15 years.
I don't believe in trying to fix something that isn't broken.

I think you are right on there. Time to retire the disposer and maybe call in someone to snake the line to the main.