Helping out non-profit in older building. Installed new laundry sink right beside new gas hot water tank. Testing it, found that i could not get full hot water (compared it to HWT drain temperature). Nor could i get cold or even cool water from COLD tap ( i ran it for over 10 minutes). Building is labyrinthe and many hands have worked on it. Staff also report that the hot water flow is undependable ans seems to run out prematurely. Installer has been back and cerified that tank is working perfectly.

I am wondering then: is it possible that a previous plumber/volunteer accidentally cross-connected the hot and cold pipes somewhere. That wouls account for the strange teperature behavuours, which do fluctuate which i am speculating arises fro pressure differneces on the two sides. Or am i just dreaming?

More importantly, how to test this without ripping the building apart? Maybe flow meters could be used? Thanks.

more likely that cold water is passing through a faucet into the hot water system.
Now how to find the guilty faucet will take a good experienced plumber and some luck.



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