Noisy Oso Unvented

I fitted this thing over a year ago, client has constantly complained of noise, but it didn't do it for me.

Today I serviced it and whilst cleaning strainer out of curiosity I blew through it, which yielded a noise like you use to make with grass as a kid. (I already reasoned it was only the strainer or the check valve that could be doing it).

Anyhow rather than just clean it I renewed it alltogether with a brand new one from another mfcv.

Hot water performance is now silent as you would normally expect.

I had already phoned Oso 6 months ago and they said they had had trouble with some of the mfcv's so I was expecting the problem to be in that region.

What is possible is that the strainer in these valves is prone to noise when scaled up slightly. My back up plan if this repeats itself is to fit a bigger and better water filter previous to the valve and take the stariner out altogether.

Anyone experienced this?

only ever found the combination valve to be U/S. try a pressure test after the cylinder if it is over 2.5 bar the valve is shot

how much scale is in the cylinder is another question - i went to a 3 year old 210L direct on saturday and removed 7 builders buckets full of scale!

the call was for no hot water coming out of the taps !

Only on a Megaflo! Out of gtee so ended up changing the cartridge which iirc comes with filter and nrv.

Thanks both,

scale isn't usually a problem in this area, but the mesh filter was scaled up slightly which is what caused the noise.

I should have put a pressure guage on it. As it's fixed for now I'll leave that for another call if I get one.

Kevin how exactly did you/would you, go about getting that lot out??!!

I fitted an Ariston last week and left it on electric heat over a weekend before commissioning the boiler heat source.

I had to renew the immersion heater washer as it was leaking and found the element already had about 1.5 mm of loose granulated scale after just two days!

Tony