I have an American Standard cadet 3 that was just installed. After flushing, the water fills into the bowl. However, after several minutes, the water in the bowl is nearly gone. The flapper appears to be seated well and not leaking. Why is this water draining like this?

Replace the tank water fill valve. Change the flush flapper too. You can get a complete kit from hardware stores.

I would check the drain line from that toilet to see if it is partially blocked and is allowing a vacumn to be drawn when another fixture drains into this line. Check the hold down bolts to floor to make sure you are getting a good seal with the wax ring. The main thing that I would suspect is that you have a toilet that was defective when it was made.Good luck and thank you.

Sorry for problem with new toilet.
You say water is leaking out of the bowl?

Toilets have 2 parts:
1) Tank: where water is stored for the flush and is sealed with a flapper.
2) Bowl: where water flushes down.

a) If tank is leaking water, then flapper is suspect. Replace flapper and see if that works.
Lift up flapper and run finger around rim to see if there is a rough spot that would indicate flush valve is defective, and needs replacement.
See typical flush valve

b) If bowl is leaking, that is very unusual and would indicate a crack in the porcelain.

If installer sold you the toilet, it is his responsibility to make good on product.
All products are guarantee against workmanship flaws.

theres probably debrie in flush valve, mite also try putting food dye in tank (any color) if it appears in bowl the flapper is seeping water and activating flush valve..

Check to be sure small tube is flowing inside the ovefow tube. This is the water that flushes the rim holes, and refills the bowl. If you don't have flow clean or replace the float valve.

We have just recently purchased one of the American standard cadet at home depot from a discount flyer and had it for about a day and took it back.

Like you said, Did not notice Any thing like a strong flush.

RECOMENDATION:

Take it back.

Home Depot also sells a Kohler Toilet 1.6 Gallon Flush Install
This is all it said it was. It saves water for sure and has a quick flush.

We liked it so much we purchased two of them because everyone in the house only wanted to using our bathroom.

Hope this tip helps.

r/
David

You have a blockage in your drainage system.

in the tank check that the small white hose is not kinked or has fallen away from the center tube where the flush flapper is located the white hose goes into the center and fills the bowl