Johnson Tee concerns

[jim Revell]

In 1981 our very professional plumber automatically installed a Johnson Tee for creating an air gap for our dishwasher. I was not aware of it intill many years later. I had had a top of the line GE dishwasher installed and it worked great for 12 or so years. I discovered the Johnson Tee when I replaced the GE dishwasher. The new dishwasher, a Whirlpool, was working fine when we sold the house. Now I want to put a Johnson Tee in my new house but nearly every appliance sales person decries them as the bain of dishwashers. Even saying that I will have to install a stronger pump motor to protect my dishwasher. They say the Johnson Tee will quickly ruin my new dishwasher. I for the life of me can't understand the problem. The physics of an airgap in the wall above flood stage seems the same as if it is on the counter? Whats' the story?

 

[Terry]

I'd like to know too. The Johnson tee and the air gap on the sink have been around for decades in the Seattle area and are still in use.
By the way, the Johnson Tee was invented by a Seattle inspector years ago.
It isn't used in all parts of the US.
Many parts of the US just loop the line from the dw.

Are the makers of dishwashers unaware of plumbing codes when they design their products?

The Johnson Tee has been used in the Seattle area. It may not be code other places.

Most homes are done with air-gaps.

 

[Sponsor]

 

[hj]

johnson tee.

That subject came up recently. I told the person that even though it would work, and it will have absolutely no effect on the dishwasher, some inspectors would turn it down for sanitary reasons. The person wrote back and said it had been rejected because the Johnson air gap is not on the approved list, and he did not want to pay an annual $3,000.00 fee to have it tested and approved each year.