Fog Horn Cold Water Pipe

[Minty_Cymru]

Hello all.

The plumping in my house is about 23 - 30 years old - looks like it was performed by the cheapest bidder. I've lived there for about 14 years and for about the last 2 years the ball valve in the cold water tank (in the attic) has 'dribbled' constantly - which obviously sent it out the overflow.

I managed to get the time to replace the ball valve this year and fitted one just the same as the one that was removed, your average normal everyday valve looked like this:

When I was fitting it I moved the tank slightly (literally by about an inch or two) this may (or may not) be significant.

Later, when refilling the tank, when the valve was near to closing I had a very aggressive vibration from the cold water pipes - I found that the piston inside the new ball valve (which was attached to the vlave washer) was vibrating inside the valve. I had no choice but to refit the old valve until I could find a solution.

I then bought a new ball valve from Focus DIY - a slightly different valve in appearence, just like this:

[DLMURL="http://www.diy.com/diy/jsp/bq/nav.jsp?action=detail&fh_secondid=9270919&fh_location=//catalog01/en_GB/categories<{9372015}/categories<{9372046}/categories<{9372180}/specificationsProductType=toilet_fittings/specificationsSpecificProductType=valves&tmcampid=4&tmad=c&ecamp=cse_go&CAWELAID=266881092"]Ball Valve High Pressure 16131201 1/2inch Part 2, 16131201[/DLMURL]

This seemd to cure the problem, until now (about 5 months later). Starting this weekend I've had 'Fog Horn' issues from the cold water system connected to the header tank. This happens when the valve is beginning to close and will remain until the valve is fully closed. For some reason there is a very long period of time between closing and fully closed (up to an hour) when you can hear the flow slowing down, going through 'dribble' and eventaully will drip for a while.

During this time I get the 'Fog Horn' in 'waves'.

My initial reaction would be to fit a new ball valve, but since this one is only 5 months old I'm a little sceptical that this is the issue.

If I could get the valve to react quicker (and not spend so much time in the 'closing' position) I'm sure this would cure it.

Any thoughts? I would appreciate any help I can get.

Thanks

 

[Pipes Plumbing]

When you changed the valve, was there a metal plate clamped against the tank to stiffen it?
If so, is it still fitted? Also, when you moved the tank, has it put the pipework or the side of the tank under strain?

If not it could be the tank flexing against the force exerted by the float valve which could cause you issues with noise and the valve not shutting off positively.

 

[Minty_Cymru]

First, thank you for replying!

There was no plate, I'm guessing this plate would go around the hole where the valve is mounted - I can get one made quite easliy, how big do these usually need to be? Any particulare materials, and should there be only one plate (on the outide of the tank)?

Yes, the pipe could be under stress. I'm thinking that tonight I'll take the valve off the pipe and see where the pipe is without any fixings, and move the tank slightly to match?

 

[Minty_Cymru]

Also, could you tell me if the second item on the following page is suitable for a cold water tank - os it a a WC cistern valve?

[DLMURL="http://www.discountedheating.co.uk/shop/acatalog/Ball_Valves___Fittings.html"]Ball Valves and Fittings[/DLMURL]

Thanks

 

[PlumbBobBob]

hi when you take the valve off check to see what colour the small funnel shaped piece is, it should be white with a small diameter hole for high pressure just wondering if it has a red one for low pressure instead which has a larger diameter hole.

 

[Minty_Cymru]

I know what you're talking about - the really old design (as per the one I removed) can be adapted for high or low pressure by changing the ?flow regulator? (funnel). The valve that is currently fitted is of a slightly differnent design which (it said on the packaging) was already set for high pressure. I didn't know if the item was servicable so I didn't dare disassemble it.

 

[PlumbBobBob]

post a pick of what you have and we can advise further. when you take off later.

 

[Minty_Cymru]

I'm not going up there tonight now, I've ordered that new valve which has a quiet fill system - as long as the fog horn is cured it's better all round because the tank is above my head in the bedroom. That will be delivered tomorrow so I may as well swap that and try to reposition the tank at the same time.

I'll strip out that valve that comes out and post it here.

Should I be thinking of getting a strengthening plate made up before fitting the new valve?

 

[PlumbBobBob]

might be a good idea will need 1/2" hole for the valve to go through assuming it is 1/2" and not 3/4" in which case get larger hole.

 

[Minty_Cymru]

Sorry, what I meant was how big should the plate be (external dimensions)

Had another look at the pipes last night - there's no clipping, at all! When the pipes go into the attic it would be impossible to clip them, but as they come down into the airing cupboard they descend the full height of the room with no clipping. Is there a 'retro' solution to this?

 

[gasmarc]

rap some insulation around the pipe where it goes through a gap may help stiffen it up which could help, I have had that before with a plastic water main that was not clipped ended up putting a concrete block on it which sorted it out, good luck

 

[PlumbBobBob]

Sorry, what I meant was how big should the plate be (external dimensions)

Had another look at the pipes last night - there's no clipping, at all! When the pipes go into the attic it would be impossible to clip them, but as they come down into the airing cupboard they descend the full height of the room with no clipping. Is there a 'retro' solution to this?

about 6 inches square would do it's just to stiffen the tank wall really make a paper template the hole will probably have to be off center because of the lip of the tank.

 

[Minty_Cymru]

Thanks.

I'll fit the new valve tonight and measure the hole position in relation to the tank at the same time, if the problem persists I'll get a plate made for me at work no problems at all, now that I know what size it needs to be I can easily get this done.

 

[PlumbBobBob]

no probs

 

[Minty_Cymru]

Looks like that new valve has sorted it - Viva la Fluidmaster! Water shut off now is instant and no noise at all. Shifted the tank slightly (not to original position) to a more natural position for the feed pipe too.

I do have one concern though, of my own making, when connecting the valve to the supply pipe I did as the instructions said - "fasten hand tight then add 1/4 turn with a spanner" the problem was that I couldn't get 1/4 turn on it with a spanner because the threaded part of the valve would turn with the nut. I gripped it as much as I could and probably got around 1/16 turn on it.

Thinking back, I realised that the threaded part of the valve had flats on either side, funnily enough they'd be just perfect to hold with a spanner to add torque to the connecting nut (so I could get 1/4 turn) :thinking: why I didn't think of this while I was up there is beyond me.

Anyway, before fitting I put a few turns of PTFE tape on the compression washer on the end of the supply pipe, and a few turns on thread of the valve. It isn't leaking, but do you think I'm taking a chance leaving it like that? It's a right pain getting up there (bedroom near enough needs to be emptied).

Thanks for the help.

 

[dontknowitall]

A fibre washer (available from plumbing merchants) is a safer and quicker fix than all that ptfe tape. Well done for so far though!