a question that has been on my mind for a few days

[jwgh]

The other day I went to a restaurant and had reason to use the rest room. While there I noticed that the hot water had been turned off in the sink, so if you turned the hot water handle to open then no water would come out. By accident, however, I discovered that if you left the hot water open and then flushed the toilet a little water would come out of the faucet. (I tested this a couple of times to make sure.)

The question is, is there an explanation for this that is not unsettling?

Comments

Clearly

[tau-iota-mu-c.livejournal.com]

What do you mean by unsettling?

Because the obvious cause is that the sewer outlet is leaking a little, as is the hot water pipe. Together, they act such that the pressure differential between them causes some of the sewerage to make it back through the hot water pipe, and out of your open hot water tap.

And why would a restaurant have a bath in the public facilities?

[sunburn.livejournal.com]

They're diverting some hot water into the toilet tank to prevent the tank from sweating, and there's some pressure problem with the sink, so that only the additional demand of a toilet-tank refill will get teh hot water flowing.

[majorzed.livejournal.com]

Anti-Scald Valve