By popular demand, I'm starting a new thread on my shower woes in the Blue bathroom. The original confusing thread can be found here: <a href="http://www.heatinghelp.com/forum-thread/146228/Plumbing-Forum">http://www.heatinghelp.com/forum-thread/146228/Plumbing-Forum</a>
IT went all over the place and the original issues became hopelessly confused (except to icesailor!), who managed to follow the details and actually knows how my shower fixture works.
Background: 100 yr old Speakman Mix-o-meter that HAD and probably STILL has a cross-connection. We replaced the gaskets and THAT stopped the toilet from from getting hot, but the sink and shower remain tepid. The sink also has very low HW flow, but I believe this is unrelated, due to a series of experiments I did today.
After a zillion years, I finally discovered where the hot & cold shut-offs in the basement are for this half of the house, but my "experiments" showed some strange things. PLEASE NOTE: a single valve controls the HW to this part of the house, but two valves control the cold water, one of which ONLY goes to this bathroom. When I shut off the cold valve servicing the blue bathroom, all cold water is shut off, but the hot water is still weak and tepid. When I shut off the hot water in the basement, I still get flow out of all the hot taps on all the fixtures, but it's very tepid.. Only by shutting off BOTH the Hot AND cold valves can I stop the flow to the hot tap. In addition, when I shut off both cold valves and turn on the hot one, the shower water becomes HOT and has great pressure.(The only time I've felt this in at least a year!) This is why I don't think it's obstructed. The sink also gets very hot, but it's still just a trickle.
I don't see how the water from the other cold valve servicing the other rooms is crossing over into the hot as I've already shut off the cold valve that supplies this bathroom. Confused, anyone? So am I.
I might also note that when I did the same experiment with the other bathrooms and kitchen, I had the same result. Shutting off the hot water did NOT shut off the flow at the hot taps. It just became tepid, but maintained a strong flow. When I then shut of the cold valve as well, all flow ceased. Someone please explain this to me. Could it all originate at the shower in question or should I check out the mixer valves in the other fixtures which are all fairly new. Is it possible this originates in the basement? If so, why is the blue bathroom that's furthest away the one with a problem. All the other bathrooms and sinks on this side are fine.
Icesailor, regarding the low-flow to the sink...I think it may be unrelated. I thought to get the shower cross-connection fixed first and then address the sink.
Why would replacing the gaskets not fix the entire problem, but only the HW in the toilet? What am I missing in how these old Speakman Mix-o-meter work?
Thank you for any and all suggestions. I intend to fix this!!!
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