Water hammer

[Johntheo5]

Yeah checked that!

I was just having a play now and I'm wondering if the hammer is coming from the multibloc - you said there's a one way valve in there? Could these make noises?

I have seen posts where replacing them did apparently get rid of the problem but obviously no guarantee.

What vol is the under sink shock arrester?, You say? the 3bar pressure doesn;t change with the mains isolated or not, I would suggest reducing the charge pressure to 2bar as that will act in a better fashion to absorb any shocks.

 

[Taconite5]

I have seen posts where replacing them did apparently get rid of the problem but obviously no guarantee.

What vol is the under sink shock arrester?, You say? the 3bar pressure doesn;t change with the mains isolated or not, I would suggest reducing the charge pressure to 2bar as that will act in a better fashion to absorb any shocks.

The guarantee ran out anyway due to a lack of commissioning docs. The installer is ignoring me requests so kinda just given up.

It’s only one of the small ones like 0.16L. Yeah I remember the manufacturer suggesting this going down 0.2 each time. Last time I tried this I was getting down to 1bar and it still wasn’t having any affect.

 

[Johntheo5]

The guarantee ran out anyway due to a lack of commissioning docs. The installer is ignoring me requests so kinda just given up.

It’s only one of the small ones like 0.16L. Yeah I remember the manufacturer suggesting this going down 0.2 each time. Last time I tried this I was getting down to 1bar and it still wasn’t having any affect.

I read somewhere where someone installed a 5L charged to 2bar with a mains pressure of 5bar which apparently worked.

 

[Taconite5]

I read somewhere where someone installed a 5L charged to 2bar with a mains pressure of 5bar which apparently worked.

hmmm

Here's more info - so if I open another tap even just a trickle and go and open and close another the noise doesn't happen.

 

[Johntheo5]

I would suggest you definitely determine the mains pressure, you should be able to this with that miny arrestor, shut off the mains, open a low down cold tap, disconnect the arrestor pipe, check the air end pressure, if its 3 bar reduce it to 1bar, reconnect the pipe, reopen the mains after closing the drain tap, then measure the air end pressure again, that should give you a true mains pressure, (as long as it's > than 1bar), I would then suggest repeat the process and charge the arrestor to the mains pressure - 1bar, see how it goes although I don't have much faith in something as small as 0.16L.

 

[Taconite5]

I would suggest you definitely determine the mains pressure, you should be able to this with that miny arrestor, shut off the mains, open a low down cold tap, disconnect the arrestor pipe, check the air end pressure, if its 3 bar reduce it to 1bar, reconnect the pipe, reopen the mains after closing the drain tap, then measure the air end pressure again, that should give you a true mains pressure, (as long as it's > than 1bar), I would then suggest repeat the process and charge the arrestor to the mains pressure - 1bar, see how it goes although I don't have much faith in something as small as 0.16L.

Think I fixed it! Strainer had loads of gunk in it!

The reason why I never questioned this is I thought it would be the first thing a plumber would have checked and therefore was looking for other problems!

 

[Johntheo5]

Think I fixed it! Strainer had loads of gunk in it!

The reason why I never questioned this is I thought it would be the first thing a plumber would have checked and therefore was looking for other problems!

Surprising that the strainer blockage wasn't reflected in poor cold and HW flowrates, this reminds me once again of one of the world's greatest mysteries, that unvented HW cylinders don't have pressure gauges.

 

[Taconite5]

Surprising that the strainer blockage wasn't reflected in poor cold and HW flowrates, this reminds me once again of one of the world's greatest mysteries, that unvented HW cylinders don't have pressure gauges.

I was debating today whether to buy one.

It’s so much quieter now.