How to un-seize a seized shower tap?

[Florine]

Hi again. I'm struggling to get a shower control plate away from the wall because the top shower tap has seized and I can't unscrew it. This sort of thing, except the quarter-turn taps are horizontal in the off position:

Hudson Reed Tec Pura Plus Triple Concealed Thermostatic Shower Valve - Chrome - A3003 at Victorian Plumbing UK

Hudson Reed Tec Pura Plus Triple Concealed Thermostatic Shower Valve - Chrome - A3003 is available from Victorian Plumbing at great Value. Hudson Reed Tec Pura Plus Triple Concealed Thermostatic Shower Valve - Chrome - A3003 is made to the highest standards, with high quality design, great build...

www.victorianplumbing.co.uk

The screw-on cover plate thingy for the bottom tap will unscrew easily enough, but the top one appears to be totally seized, despite liberal application of WD-40, and I need to be able to unscrew it at least because the tap is loose and the screw is hiding behind it, and possibly also because I want to see what's going on behind the plate. Does anyone have any recommendations for getting it un-seized, please?

 

[blup]

You can try wd 40 but probably have to drill it out, unless you can loosen it sufficiently first.

 

[Florine]

Oh dear, what a pain, but thanks. Am currently trying a new way of applying WD40, but am wondering if rigging up some sort of contraption with a yoghurt pot and some vinegar would actually work better. Depends on what's causing it to seize, I suppose.

 

[opps]

I am not a plumber...

My crosswater valves can be replaced without having to remove the faceplate. The plate has o-rings on the reverse side to prevent water running behind it.

 

[Florine]

No, my main concern is to get the seized screw cap thingy off the top tap so that I can tighten the screw behind it. As well as potentially seeing whether anything untoward is happening behind the plate.

 

[opps]

Does the following help?

Hudson Reed | Showers | Triple Valves | Triple Thermostatic Shower Valve

Products | A3003 | Triple Thermostatic Shower Valve

www.hudsonreed.co.uk

scroll down to fitting instructions.

It looks like you need a spanner.