im sure this is a commom question
can someone tell me that if my shower is running and someone runs a tap or flushes the w.c the temp gets really hot in the shower for about 1 min.
its a brand new combi boiler we got 1 year ageo when we moved in (worcester) this never happened in our old house?
i have young children so this iw a worry!
Possibly the shower isn't one that is designed to run off a combi, or it's not thermostatic, or, as someone has mentioned, the cartridge in the shower is faulty.
Perhaps you could tell us the make and model of the shower valve.