Limp Arbor wrote:
I work in a 4 story building with standard commercial toilets and
urinals. For some reason when the valve for the spray arm is left on
in the kitchen the toilets and urinals get supplied with hot water.
Kitchen is on the 2nd floor and the warm toilets affect at a minimum
floors 1 through 3. The building has circulator pumps in the
basement.

Could this possibly be by design?

b) No

a) My conjecture would be there's a recirculating valve for the hot
water that has failed allowing crossover.

In a large building there's always the outside chance that a supply line
got crossed somewhere but the indication here that's not the issue is
the correlation w/ the spray arm not all the time.

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