The 50 gallon gas water heater is on the first floor. Water pressure coming into the house is roughly 40 psi. On the second floor the kitchen and bathroom faucets are cold when turned on. I mention it, but it might be due to the design of the house. On the third floor in the shower, when turned on it runs cold, then a normal temperature, then it starts progressively getting colder so I have to keep turning it up. After taking a shower, a faucet in the same bathroom runs scalding hot. Giving it a minute, it gets to a more normal temperature. The mixer in the shower is an old design, the faucet is brand new. Water pressure everywhere in the house feels a little weak.
Plumbing – Shower runs cold, then hot, then cold. Faucet in same bathroom runs hot after shower
hot-waterplumbingwaterwater-heaterwater-pressure
Related Topic
- Water – What could cause a shower to give warm water for a few seconds, then only cold water
- Plumbing – What could cause low hot water pressure only in the line to one shower
- Plumbing – Showers in house run cold after 30/45 seconds – Sinks scalding hot
- Plumbing – Single-lever shower faucet – no warm water; just hot/cold
- Water – After replacing a recirculating pump (and pressure regulator), shower won’t run hot
- Plumbing – Newly installed thermostatic mixer runs cold when shower head raised in height
- Plumbing – Shower Runs out of hot water after a few minutes but sinks stay hot at the same time
Best Answer
Besides clogged pipes as described by Programmer66, thermostatic shower valves are known for this problem. The cold and hot water side is mixed upstream of the closing valve. In normal faucets, the mixing is downstream of the valves. To avoid cold water to be pushed into the hot water pipes (and vice versa), thermostatic valves have special pressure balancing or one-way valves that could be made with diaphragmas, which are not reliable in the long run being a rubber-like thin material, especially the element in contact with the hot water. A Google search "thermostatic shower valve temperature problem" will present many Infos including DIY videos.