Hi!
I have a problem with my shower water- I turn the knob all the way as hot as it can go, and for about a min or 2 its burning hot, then drops to ice cold for a min or 2, and then gradually gets warmer again. It never stays a consistent temperature. I'm tired of taking cold showers! I have a boiler/ oil heat and was told adding a mixing valve may help correct the issue..?? The water in the sinks in the rest of my house (and even that bathroom) is scalding hot and stays that way, only having a problem with the shower. Any ideas?

if the water at the faucets is scalding hot, you need a mixing/tempering valve anyway..
as for the shower, try running the faucets at the same time the shower is running. see if they act the same..
if they are consitently hot while the shower fluctuates then the problem lies with the shower valve.
you will have to get us a description (make and model) of the valve so an intelligent answer can follow..

Besides the make and model of faucet, do you have a recirculation system?

The sink faucets also become cool when the shower water does. As soon as I turn the shower off (and leave the sinks on) the sinks become extremely hot again within seconds. Also, where do I find the shower valve to check the make and model? (Sorry, but please bear with me- I'm very incompetent when it comes to plumbing....). As far as I know, I do not have a recirculating system.



Edited 1 times.

If everything is going cold, but you you still have hot water in the tank and no recirculation system, then the water is either crossing over somewhere, or it isn't drawing from the tank properly and sucking cold water from the inlet to the outlet.

So would you recommend I call a plumber to come look at it?