Gradually loses shower pressure

[fuzzyone]

Hi all,

I posted awhile ago my problem with the mixer shower in the ensuite on a gravity fed system - //www.diynot.com/forums/plumbing/shower-hot-water-low-pressure-only-now-fixed.358179/

It has started to dribble every now and then which is annoying, the last time i fixed it was to let the shower head hang on the floor with the water on and I can hear air/bubbles coming out from the mixer.

I think i need to let it run for a while 15mins+ to regain some or even most of the pressure back so surely its an issue with air getting trapped? The pressure in the bathroom doesn't seem to be affected as the shower head in there has never really lost pressure.

Anyone has anything similar? The cartridge was changed a few months ago and didnt seem to help much so my only option at the moment is run the water with the shower head on the floor and intermitten air is head, sometimes loads of air all at one and then dribble of air every second.

Any advise is appreciated!

 

[Servotech]

First thoughts is that the shower as insufficient head of water.
The shower head needs to be a minimum of 1 metre below the base of the tank for it to work properly.

However, as you say as worked normally in the past so it could be trapping air in the pipework.

Make sure that the ball-valve in the cold water is filling at a good rate.

If all the above are fine here is a little trick to get air out from the shower pipework.
1 Take the shower head off
2 Fill the bath or sink with water
3 Pull the plug then adjust the flow from the tap so that the sink or bath stay full and the water that is draining away is replenished.
4 Now turn the shower on and place the hose under the water and keep it there for a few mins swoping it from cold to hot.
5 Seems an odd method but it does work I assure you.

 

[fuzzyone]

Hi,

Thanks for the response! Some clarification need.

Is this performed on the affected shower (ensuite), if so the shower hose is not long enough to reach the basin so i'll need to get a longer hose for this?

This water pressure issue affects only the hot water for the ensuite shower, all other taps, baths, etc are of normal pressure.

Does seem strange this method, water is drained which shouldn't affect air as it's different pipe?

 

[bamber]

1 Take the shower head off
2 Fill the bath or sink with water
3 Pull the plug then adjust the flow from the tap so that the sink or bath stay full and the water that is draining away is replenished.
4 Now turn the shower on and place the hose under the water and keep it there for a few mins swoping it from cold to hot.
5 Seems an odd method but it does work I assure you

Ha, Ha, Ridiculous!.. your shower head is higher or close to the base of your header tank.

 

[stardanny]

How is the hot feed to shower connect to cylinder?

Air has somehow got in pipe supply to shower.

Make sure the cold feed to cylinder gate vale is fully open.

Daniel.

 

[fuzzyone]

Cold valve to hot cylinder is fully open.

Hot feed goes from cylinder, under the floor to the back of themail ensuite shower. The same pipe is linked to the bath tub mixer.

I just tried taking shower head off, turn on mixer with 50/50 temp then blocked the hose with my thumb for a few secs as the bag trick failed as it split. Seems pressure is better now bit still can see and hear bubbles coming out, don't really want to sit and leave water constantly running. Perhaps I'll get a really long hose and fill the bathtub this way lol

 

[stardanny]

Cold valve to hot cylinder is fully open.

Hot feed goes from cylinder, under the floor to the back of themail ensuite shower. The same pipe is linked to the bath tub mixer.

Is the hot feed straight from top of cylinder?

The bath mixer, does it suffer from same problem as shower on hot water? If the bath mixer is ok, it might be the shower itself...

Daniel.

 

[fuzzyone]

Yes I think it's top of cylinder.

Bath doesn't seem to be affected, the triton mixer in ensuite had its cartridge changed before.

Right now if the hot water is used in ensuite, bubbles can be heard coming out of the hose.

 

[Servotech]

1 Take the shower head off
2 Fill the bath or sink with water
3 Pull the plug then adjust the flow from the tap so that the sink or bath stay full and the water that is draining away is replenished.
4 Now turn the shower on and place the hose under the water and keep it there for a few mins swoping it from cold to hot.
5 Seems an odd method but it does work I assure you

Ha, Ha, Ridiculous!.. your shower head is higher or close to the base of your header tank.

No no, it's a genuine trick that works if you have genuine air in pipework problems.
I've not used it much I admit, but it's one well worth having in your locker.

For the (shall we say unscientific) amongst us - it's setting up a syphon and pulling the water through the shower via syphonage (as long as the end of the shower is kept under the water it works).

 

[Servotech]

Hi,

Thanks for the response! Some clarification need.

Is this performed on the affected shower (ensuite), if so the shower hose is not long enough to reach the basin so i'll need to get a longer hose for this?

This water pressure issue affects only the hot water for the ensuite shower, all other taps, baths, etc are of normal pressure.

Does seem strange this method, water is drained which shouldn't affect air as it's different pipe?

You need to do it on the affected shower.
It's one you that won't find in any plumbing manual !

 

[HERTS P&D]

Or use a wet vac and suck the air out Rog.

Andy

 

[fuzzyone]

the syphon method didn't really seem to work.

Instead I used the kitchen mains water connected to the downstairs toilet hot water tap to push the air back up into the tanks. This seems to have done the trick, the overflow pipe at the top splutter a bit of water and air. The hot water feed from the water tank had water going back to it and I can see loads of bubbles.

That and letting the shower head hang on the floor with the water turned on (separate test) seems to have restored my shower pressure for the hot water!

I have also bought an adapter (£1 from b&q) to fit to the shower unit so next time I can push with mains pressure the air bubbles back out to the water tank. Just need to buy a longer hose.