Hi folks,
I've discovered through a tortuous process of elimination, by turning stopcocks on and off and playing with taps, that I'm getting a back flow from the cold supply, via a Grohe thermostatic shower valve, into my unvented hot water cylinder, which eventually builds up enough pressure to trip the pressure relief valve.
The thing is, this has been a kind of intermittent problem before, but this morning it finally became an issue I couldn't ignore.
I have no idea if a grohe valve would have built-in check valves or not, or whether there were external ones fitted to my shower which was fitted about 5 years ago. Most of the pipework is totally hidden.
Why would it suddenly go bad like this? Is it a build up of limescale or something? My plan is just to put a check valve into the hot feed to the bathroom, where I can easily get at the pipework.
Any views on what causes this type of thing?
Matt
I've discovered through a tortuous process of elimination, by turning stopcocks on and off and playing with taps, that I'm getting a back flow from the cold supply, via a Grohe thermostatic shower valve, into my unvented hot water cylinder, which eventually builds up enough pressure to trip the pressure relief valve.
The thing is, this has been a kind of intermittent problem before, but this morning it finally became an issue I couldn't ignore.
I have no idea if a grohe valve would have built-in check valves or not, or whether there were external ones fitted to my shower which was fitted about 5 years ago. Most of the pipework is totally hidden.
Why would it suddenly go bad like this? Is it a build up of limescale or something? My plan is just to put a check valve into the hot feed to the bathroom, where I can easily get at the pipework.
Any views on what causes this type of thing?
Matt
