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We moved into our newbuild house october 2012 and the Mira Shower was fantastic. We live in Inverclyde and AFAIK like most rest of Scotland we are not in a hard water area.

Our heating and hot water system is powered by a heat only boiler and we have a large hot water tank with two header tanks - one red, one white in a cupbord.

All of a sudden, after a year of flawless performance, the pressure on the shower reduced markedly, we called persimmon who built and sold us the house, they sent round a plumber who said we needed to get someone from Mira to come out.

Waited another week and the guy from Mira came out - none too pleased as the original plumber didn't check the filters - he showed the blocked filters to my wife before cleaning them - she told me it was both the cold and hot water filters.

The Mira guy thinks that it's plumbers paste.

The shower was back to it's best - for a couple of weeks then the pressure dropped again - called persimmon again.

Plumber comes out, turns of the cold water under the kitchen sink and takes apart the shower, looks like this time it's just the hot water filter that is clogged with unidentified "gunge".

He cleans that and turns on the water again - the bathroom sink mixer (ideal standard) tap starts to splutter as you would expect then water starts to flow out as normal - then stops completely - I assumed (wrongly) he had turned off the water again but no the tap is all of a sudden defective - still is as I write this and I have no idea of when it's going to be fixed

Back to the shower: he runs the shower and within minutes, the flow has reduced so off with the water and have another look at the filters - blocked again!

I asked him what he thought it was - being what looked like a "time served" man I would have expected he would have seen stuff like this before - he said he didn't know - it was his company that did the plumbing when the house was built.

He ran water through the pipes without the shower assembly attached to flush out whatever gunge was left.

Refixed the shower and ran it again, within a minute the hot filter is blocked again with more gunge - his solution was to replace the filter with a filterless washer!

That seems to me to risk the gunge clogging up the rest of the shower (which long term would be worse) he was of the opinion that the particles would pass through the shower OK - presumably onto us!

He is going to come back at some unspecified date and fully drain the system

I am in the position just now that I am considering putting the filter back myself and putting up with the reduced flow until this happens.

What I would like to know is what is this gunge likely to be - how much of it is in the system - what damage it is causing - and why is it only a problem after a year

Any help greatly appreciated

Hi
From your description, the supply is tank fed, although I'm not clear on red and white tanks, I suspect the red one is an expansion vessel.
I don't think 'plumbers paste' is the answer, there couldn't be enough in there to cause a problem, and after a year !
Now, I could be wrong, but what comes to mind is bacteria building up in the storage tank. this can make a surprising amount of very disgusting jelly like gunk. This might explain the worsening situation.
The only way to find out would be to examine / test the material.
You may be able to get your water authority to do a test. but anyway the system is going to need a really thorough clean, and some action taken to prevent this happening.

proptech wrote:Hi
From your description, the supply is tank fed, although I'm not clear on red and white tanks, I suspect the red one is an expansion vessel.
I don't think 'plumbers paste' is the answer, there couldn't be enough in there to cause a problem, and after a year !
Now, I could be wrong, but what comes to mind is bacteria building up in the storage tank. this can make a surprising amount of very disgusting jelly like gunk. This might explain the worsening situation.
The only way to find out would be to examine / test the material.
You may be able to get your water authority to do a test. but anyway the system is going to need a really thorough clean, and some action taken to prevent this happening.

thanks for the reply i'll try to attach a pic of the tanks

Thanks for the photo. That's not the type of system I had in mind. I was expecting an open storage tank when I mentioned bacteria, clearly that is not the case.
So, I'm out of ideas now. this will just have to be investigated on site, or the 'gunge' tested in some way.

proptech wrote:Thanks for the photo. That's not the type of system I had in mind. I was expecting an open storage tank when I mentioned bacteria, clearly that is not the case.
So, I'm out of ideas now. this will just have to be investigated on site, or the 'gunge' tested in some way.

All about a year old so there should be no gunge at all - they are coming to flush the tank on monday afternoon

Good to get the feedback. Please let us know if anything is found.

proptech wrote:Good to get the feedback. Please let us know if anything is found.

Wasn't in but my wife told me, Tank was drained from the top as a washer from the tap at the bottom was causing a problem, then washer changed and further draining from the bottom - flushing was mentioned but I don't know what that entailed.

I am told that the filters were put back into the shower.

Still the pressure in the shower is not what it was

Not happy

Thank you for that, It really doesn't seem right to me. I wouldn't have thought a washer, even if it had disintegrated would be the cause.
One other suggestion - how about contacting the manufacturers of the cylinder, their name's all over it, and see what reaction you get from them. That type of cylinder is quite complex, and they know it more than anyone.

Have you had the tap sorted yet??

What's the betting one of the flexible hoses is blocked with the same gunk?? The bore of these pipes is often only 5mm or so.

plumbbob wrote:Have you had the tap sorted yet??

What's the betting one of the flexible hoses is blocked with the same gunk?? The bore of these pipes is often only 5mm or so.

A new tap was fitted and like you I would not be surprised to find it blocked - I wasn't there so didn't see the "cartridge"

Still no word on what the gunge is or how it got into the syatem and only became a problem after a year can't believe that experienced plumbers woudl have no clue - I have contacted persimmon again and they are going to arrange for another visit from MIRA , will be interesting to see what they find.

proptech wrote:Thank you for that, It really doesn't seem right to me. I wouldn't have thought a washer, even if it had disintegrated would be the cause.
One other suggestion - how about contacting the manufacturers of the cylinder, their name's all over it, and see what reaction you get from them. That type of cylinder is quite complex, and they know it more than anyone.

I'll try emailing them, I don't think that the washer on the tank was the issue just that it made draining harder and draining from the top would just leave the gunk at the bottom I would have thought - though my wife tells me that he did eventually attach the drain at the bottom too.

MIRA guy just been refused to reposition the temp safety valve setting that was messed up by the original plumber- so will have to have ANOTHER visit - the hot water filter was blocked up with the same gunk !

Will monitor the flow over the next couple of days

time for an update,

still no resolution, have had several more visits - persimmon have been in contact with the cylinder manufacturer, they are talking in terms of flushing the tank using Argon - whats that all about?

they also found gunk at the hot water pipework in the bathroom

I bought a water pressure guage is there an adapter that will allow me to fit it to the outlet from the shower valve, the guage has same connector that you get on washing machine pipes

Sorry to be of so little help. no idea about argon flushing. Shower outlets are normally 1/2 inch BSP. Washing machine connections 3/4 BSP, so a simple 3/4 to 1/2 brass bush should do the job. The problem being that you need to have the water running in order to test the pressure, otherwise all you will read is the static mains pressure.

proptech wrote:Sorry to be of so little help. no idea about argon flushing. Shower outlets are normally 1/2 inch BSP. Washing machine connections 3/4 BSP, so a simple 3/4 to 1/2 brass bush should do the job. The problem being that you need to have the water running in order to test the pressure, otherwise all you will read is the static mains pressure.

Thanks for that plan is to attach pressure guage to shower outlet that the handset is connected to and put it on full power

update

hot water cylinder to be replaced, hopefully sooner than later, still no idea what the gunk is, hopefully that will be the end of that