Shower Problem

[John]

You may recall I have been doing my neighbours en suite room. As part of the refit they wanted a new hose and sprayhead on the shower, which they supplied. The shower does not perform as good as it did before the refit. The shower valve was never removed or isolated so I do not think it is a water feed problem. The riser rail is more or less in the same place as before and the sprayhead is at the same height. The sprayhead is a little bigger than before maybe 20mm more diameter, unfortuneatly I do not have the old one available to do a before and after comparison! Any ideas as to the problem and solution?

Am I correct in thinking that head height of water is the distance between the bottom of the loft feed tank and the showerhead? In this case that distance is approx 1.4 metres. The hot water tank is in the airing cupboard directly behind the shower wall, although it has always been there so that shouldn't be a cause of the problem.

Regards

John

[Graham]

Could it be the new hose? Check its i.d. is not narrower than the old one. The narrow ones are no good for low-pressure systems.

[John Stumbles]

Nearly: it's from the top of the water in the tank, not the bottom.

It could be the new shower head has smaller nozzles than the old one.

[John]

Somebody else told me this today, I cannot compare as the old hose has gone to the tip. If the new hose is a smaller diameter wouldn't that increase the pressure similar to putting your thumb over the end of a garden hose, or am I talking tosh?

Cheers

John

[Martin]

I don't think so. AIUI, the narrower dia hose will reduce the pressure & volume at the spray-head, whereas the "thumb on hose" determines how you use the pressure / volume already delivered at the hose outlet.

[Stickems.]

Disconnect the feeds to the mixer valve, remove and clean the filter and flush out the feed pipes before you put it back together.

[ARWadsworth]

The new shower is not meant to be run under mains pressure or anything silly like that?

Adam

[Dave]

Water through any pipe will have a finite pressure if it is restricted at the outlet end. Imagine a hose pipe.

Increase the diam. of the pipe and the pressure will stay the same, assuming that the open end stays the same also, but the flow rate will diminish through the larger diam pipe. This assumes that the source can maintain the pressure across all flow rates. (Head of water)

Putting your finger over the end of the hose restricts the flow rate and causes a jet of water to form. This jet will never get near to the level of head of water, no matter what you do with pipe sizes.

Back to the original question...

If the shower head has more holes, or has larger holes, then the diam of the pipe has been increased, hence the lower flow rate and the feeling that the shower is not as good as before. This is what I suspect the problem is.

HTH

Dave

[John]

The actual shower valve has not been replaced, I am talking about a new hose and sprayhead. What I am going to do is 'borrow' a neighbours original head and hose and see what happens then.

Thanks for all the replies guys.

Cheers

John

[Alex]

Shower heads are sold with a recommend as to the source of supply,i.e. electric,pumped or gravity,look on the packaging to see what yours will work with

[vroomfondel]

I had a similar problem. Quite by chance I noticed the new hose and head had a no-return valve insert that was reducing the flow by around 1/3rd I prised it out and chucked it away. Presumeably this is to meet some regulation about backflow if showerhead is left in bath water.

[S S]

Maybe a poor example but if you have a garden hose turned off at the `spray` end so that no water is coming out and then put a pin prick in the hose, the amount of water coming out the `pin prick` will be considerably less than if using the sprayhead. So possibly the smaller diameter does effect it.