Showertrackworld – convert olive to threaded

We currently have a very old Mira excel thermostatic shower that howls like a banshee. Cartridges are expensive and this one only lasted 2 years. I’d like to replace with a grohe bar shower that costs less for the whole shower than the Mira cartridge but have found a possible issue. The mira uses olives with a nut screwed to the body where the grohe appears to need threaded tails on the wall. Is it possible to convert one to the other? Have tried searching but not found anything that looks like it would do this….

What water supply and pressure do you have? Is it mains cold and gravity / combi hot? I only ask because if there’s a wide difference between the two, your new shower may well howl in a similar way.

Some modern showers can tolerate this, others need the cold equalised. We solved the issue temporarily by part closing the isolating valve on the cold feed. A pressure reducing valve is the other option. The max difference is normally part of the shower specs.

For your other query, stick up a pic of what you have currently and what you’re trying to fit. You can get a backplate which sits on the wall and gives you tails at 150mm centres, whether that’s easy to convert depends on your current pipe configuration.

Photo?

The mira will have 15mm pipe out of wall at 150mm centres, if you can get the olives off cleanly, you may be able to use some shower bar fixers, then the Grohe shower will attach to those.

https://www.toolstation.com/round-bar-valve-fixing-kit/p57883?store=P4&utm_source=googleshopping&utm_medium=feed&utm_campaign=googleshoppingfeed&mkwid=_dm&pcrid=null&pkw=null&pmt=null&gad_source=1&gbraid=0AAAAAD-vLcWWlNaB_VqDvByLSAi2vfgrH&gclid=Cj0KCQjw_sq2BhCUARIsAIVqmQunDy2toYTiUVL3ANyw_XgFadUbI238Q-H5sy5RJr5v_C8dFcE_VnsaAu_QEALw_wcB&gclsrc=aw.ds

I suspect the pipe work may be too short though, you normally need 25-30 of pipe work out of the wall to get the bar fixers on.

It’s a combi with mains cold water. No tanks anywhere. We have two of these showers and before the last cartridge failed (lost temp control) neither shrieked. The other one still doesn’t. I don’t know the pressure difference or pressure. For some unknown reason the shower has no isolation valves. The pipes are only accessible under the tray so if I fit valves I think it would have to be push fit. Are the pressure equalising valves fitted on the shower or whole house?

This is what’s there currently. The mira manual gives the same numbers as blazin-saddles. The grohe is the same spacing.

If the grohe is rated for a bigger range of incoming pressures, just slap it on.

Blazin has the answer but if you can’t do that you might be able to fit a 15mm x 3/4” chrome plated male iron straight onto your existing pipework

Cool, thank you all. Definitely going to need to fit isolation valves I think to remove the time pressure.

Even though they’re part of the water bylaws a lot of combi/shower setups don’t have isolators fitted (a) most of the time there’s nowhere accessible to fit them and (b) they sometimes leak.  I’d not fit an isolator anywhere I’d not be able to change one out, although people fit them under floors and in stud walls all the time, I personally wouldn’t.   The water can be turned off and drained down easily on a combi system so I’d not bother trying to retro fit isolators.