I'm a maintenance tech at an old office building which has had a lot of additions and modifications to the plumbing system which has a hot water circulation loop. I recieved a request to check out a problem in a kitchenette sink. What's happening is when you run the hot water it takes a few seconds to get hot (quite hot), stays hot for a half minute or so then cools off and gets cold again. We've had different plumbing work done in the building by some questionable contractors and I'm sure one of them has crossed the hot/cold water lines at some point, (I think this problem has existed for a long time and was just reported) but....how can the water get hot then cold on a loop? It seems to me that if the lines were tied in wrong the water would never get hot to begin with.
strange problem
- Thread starter willlgord
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water heater dip tube may be the problem
The tube would be the obvious suspect but the water heater's fine, the problem exists in this one area only. The building is about 130,000 square feet and is supplied by one hot water heater on the first floor with a HW loop circulation pump which runs 24/7. The sink is on the third floor. A few months ago another area was remodeled and more plumbing fixtures were added. I'm quite sure the contractors somehow tied the HW loop and the cold lines together at some point. We found another area where work was done a few years ago where they did something similar and a urinal now flushes with hot water, another case where the HW loop and cold were tied together but...at least the urinal water stays hot! We haven't found and repaired the urinal problem as the building is almost 100 years old and finding the problem would entail tearing walls open and such.
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lots is possiblle, water will always take the path of least resistance so opening a cold faucet that incorrectlly has a hw loop on it could cause a sudden fluctuation in pressures and allow for some hot water to be syphoned... there are many possibilitys, but basically you need to find an fix plumbing problems or they will grow and become real issies. a hot urinal you say? i see future cracked porcelain in your future. I would start fixing the problems you know about and work towards an end. the company that did the shoddy work should be liable for fixing their mistakes.
what type of piping? if its copper perhaps there is a section on a heating duct or even the vent for the HWT itself..
Bottom line, you need more compitant plumbers than the ones your using if this is the type of work they are known to do.
what type of piping? if its copper perhaps there is a section on a heating duct or even the vent for the HWT itself..
Bottom line, you need more compitant plumbers than the ones your using if this is the type of work they are known to do.
