Two days ago, my plumber had capped existing hot and cold waters lines in one of the shower and tub area as part of the remodel process. Since then I did not get hot water anywhere in the house. I rushed to change the water heater today and still no luck. Now I get some warm water in some bath and cold water. The funny part is that even after I shut down the cold water under sink, I get only cold water from hot water line. The water heater is working normally it seems.
Looks like one of these things is happening here
- Sediment build up – after installing the new heater today, I got muddy/gray water with lots of air in one of the bath
- Bad design, like hot and cold water mixing – I could be wrong as I never had this issue for the past 15 years living in the house
- Leak – We had bad weather in Dallas few weeks ago… so it might have cause but the issue is showing up after 3 weeks.
- My plumber did something silly two days ago. With my basic knowledge of plumbing, all he did was capping the lines to Tub, and installing a new valve for shower. Could he have cause some blockage?
I highly appreciate if you can shed some light.
Best Answer
The cold water could have a higher pressure, and if a backflow preventer is defect, the cold water will enter the hot water tubes. Thermostatic faucets are prone for that failure. See also Hot water turning cold in pipe at branch line