Squeaking Mixer shower

[wilks]

Hi, I am new to this forum and was wondering if anyone has a solution to a problem that is driving me up the wall. Had a Mira Minibelle mixer unit running off a 20 year old Vaillant Combi Boiler for several years. First 18 months, no problem but for about the last 2 years it has been making an almighty squealing noise when operated. Contacted Mira who suggested that mains water pressure may have been increased by water company. I checked it. It is 3bar. Unit says will operate at 5bar. If i turn on cold tap in sink next to shower, noise reduces or sometimes goes away. Mira also mentioned getting a plumber to balance the hold and cold supplies. Plumbing supplies shop recommended fitting Pressure Reducing Valve to mains feed to house. Another supplier reckoned new more substantial unit might do the trick. Happy to give the job to a local plumber don't want to spend money and find problem still un-resolved. Help!!!:sad:

 

[JCplumb]

It could be something as simple as grime in the filters, I'd phone a local plumber to come and service it, he may sort the problem in an hour.
Some noises will be familiar to a plumber and he may know what the problem is as soon as you turn it on. As long as it's a combi the pressures should be close enough to not cause any problems.
Make sure you get a recommended plumber and not the cheapest one you can find, one of us guys may even be local to you, stick a post in the [DLMURL="http://www.ukplumbersforums.co.uk/im-looking-plumber-gas-engineer/"]Looking for a plumber[/DLMURL] section of this site