Volume In, Volume Out - The Old VIVO Drain

Volume in, volume out - the old VIVO drain.

When you flush a toilet, physics takes over.  There is a special trap arrangement in the toilet structure, which has water at the bottom of the bowl, and when a flush happens the water volume (weight) flowing down causes to push upward and then downward again, FLUSHING the contents in the bowl into the drain.  The flow of water works with itself, dynamically causing the volume (weight) entered to exit, leaving the same amount of water in the bottom of the bowl.

A sink or bath tub drain works much the same way.

Water always resides in the bottom of the trap.

This water essentially plugs the drain also, so sewer gases do not enter the home.

Volume in, volume out - the old VIVO drain.

Sometimes a trap that is unused for a time will evaporate the water out leaving the way for gases to come into the home.

One of the first things I do when I enter a house for an inspection is turn on the dishwasher.  I examine it to see if it's buried behind ceramic tile or hardwood flooring, and if it's attached to the cabinet or counter top, and turn it on.

Such was the case with a recent inspection of a flipped house.

I turned on the dishwasher and let it go.

Returning later to the kitchen I noticed that as the dishwasher drained the left sink filled up with water.

The dishwasher drains into the disposal, which is under the right sink, so this filling of the left sink shouldn't happen.

I had not looked under the sink yet.  It was time to look!

What I saw was a very deep trap.

A trap should only be 4" deep or so, like in the diagram above.

When it's deep, and especially when two sinks combine, the arrangement holds a lot of water.

A proper trap might only hold a couple of cups of water.

This trap is holding a lot more, as shown, more or less, by the blue I painted in!

And so, here, as the disposal fills with water trying to drain, unless there is enough volume (weight) of water above to force the lowest water below up and out, things will drain slowly.

I turned on the faucet to demonstrate and take a photo.  It filled higher than that.

So, the VIVO principle is alive and well!

Want a natural tip for cleaning clogged drains (in a proper P-trap that is)?  Mix together very well 1 cup baking soda, 1 cup salt and 1/4 cup cream of tartar (I know, you don't have any).  Pour 1/4 cup of the dry mixture into the clogged drain.  Follow that with 2 cups of boiling water.  Let it sit for 1 hour.  Flush the drain with a lot of water weight.  How?  Fill the sink or tub with water and remove the drain plug.  The formula breaks up the mess and the water volume (weight) will wash it down.  If one application doesn't work, try another. 

Baking soda and white vinegar works on some lesser clogs.  Pour down 1 cup of each.  But be sure to cover the drain and over-flow hole with a wash cloth to contain the chemical reaction.  Letting it sit a while will break up the fats and such and then do the water volume (weight) flush.

My recommendation:  run some water into a drain and watch it drain.  Listen too.  It should go down easily and there should be no glub-glub when it finishes.  Glub-glub is a technical word.  Look it up.  If things don't go well, look underneath!  See what surprises are in store!  When Flipper is involved, well, you might just be in for a treat.