How does a previously hot water tap suddenly switch to cold & the cold switched to hot?

Question

When I moved into my house, all the taps labeled HOT produced hot water and the COLD gave out cold water. I went on vacation for a few weeks and when I came home, the cold is now HOT and the hot is now COLD. But it's only in my bathrooms, not the kitchen. People look at me crazy when I say this and tell me I must not remember and it was always probably always backwards. But I'm no fool, I've taken enough showers to remember which side was hot and which was cold. Does anyone know what could have caused this?

Answer 1

Hi, I'm assuming your in the UK in which case I have heard of faulty "Indirect" immersion heater tanks causing this sort of problem.  There is a coil of pipe that carries water through the tank, if this has a leak in it the water can in effect become hot where it should be cold and vice versa.

Good Luck  

Answer 2

What you describe is not possible, unless you have a single valve shower. If that's the case your valve is faulty. Other than that someone would have had to change the piping.

Answer 3

Moen single handle valves have the ability to switch the hot and cold by pulling off the handle, moving the cartridge 180 degrees and reattach the handle. If your handle is loose this may have happened inadvertently.  

Answer 4

after just doing some faucet work in our house, there is no way that could happen unless someone just changed all of the piping leading to the faucets, or actually switched the feed from the cold valves and hot valves around.