Changing a Bathroom suite

[supeRDerek]

Was here a few years ago and the advice was excellent - so here we go again.

I am changing a bathroom suite.

Yesterday I removed the bath and added two shut off valves to the hot and cold pipes to the tapes. See the picture........

Valves are fully open..

I now seem to have very low water pressure thru the taps. Used to have a good blast - now it seems like just a gravity flow.

Plus the shower room shower also seems to have No pressure behind the water - the pipe work to the shower is not in the bathroom system.

Have I missed something here..

 

[Dan Robinson]

I suspect those taps are not suitabel for low pressure installations.

Is yours gravity fed?

 

[supeRDerek]

Ah! Yes tiz.

Had a look at the tap box - says I need 0.5 bar....

But why would it effect the shower

 

[ChrisR]

They're gate valves so shouldn't cause any resistance.
Possibly you've got a partial air-lock in the pipes?
Are the bath taps new?

Easiest fix is an aquavac if you have one , otherwise do a search!

 

[supeRDerek]

Taps are new.

Aquavac. - Did a search - vacuum cleaner. Better explain a bit more please....

 

[Dan Robinson]

Put the water hoover over the spout. turn on cold, turn hoover and suck like... ahem.

Do the same for the hot but you need to plug the vent pipe temporarily.

Do you have 0.5 bar?

 

[supeRDerek]

Before I started I had good pressure in the system - how would I know if I had 0.5 bar

 

[Dan Robinson]

Do you know the dsifference between pressure and flow?

You measure both before you start a job so that you know what you can get away with.

You measure both afterwards to see what has happened in the interim.

 

[TicklyT]

Before I started I had good pressure in the system - how would I know if I had 0.5 bar

Quote from Wikipedia:- "In water, a measurement in decibars is approximately equal to the depth in meters; 1 decibar occurs at a depth of 1.019716"

Assuming your system is fed from a cold water storage cistern in the loft, measure the vertical distance from the base of the water tank to the tap outlet in Metres. Divide by ten and the result is near enough the water pressure in Bar.

Measuring from the base of the tank may be a bit pessimistic, but does allow a bit for any pressure drop as water flows through the system.

A typical pressure on a gravity system , with a cistern in the loft directly above the bathroom would be about 0.2 Bar

 

[supeRDerek]

Looking at all the taps forsale around various sites I see loads with 0.5 bar or 1 bar minimum.

Could I presume that a tap set with NO rating is ok for gravity fed bathrooms..

Don't seem to find taps listed with "OK for Gravity systems"

Many thanks for the help guys - always beleive the way to learn is too get stuck in and give it a go. Then learn by your mistakes

 

[Dan Robinson]

Never assume anything. If you are indoubt ask the seller/manufacturer if its suitable.

If they say yes and it turns out to be wrong, then you can send it back.

Don't buy from ebay.

Ideally the product shuld say "suitable for low pressure" or something similar.

Crosswater for example, put HP and LP next to their model numbers. I always work that if somethngi doesn't say LP on it then its only suitable for high pressure and flow installations.

 

[supeRDerek]

Never assume anything.

Thats why I was asking here...

 

[Dan Robinson]

Buying stuff like this on the tinterweb is a bit hit an miss unless you know exactly what you are getting and are familiar with the product.

We can only advise you one principles and products we have info on.

 

[supeRDerek]

Have changed the taps to some low pressure ones. Flow thru the taps is a lot better.

The shower on the bath is lacking some power though - wandering if the smaller bore of the gate valves is restricting the flow.

 

[Dan Robinson]

What is the head on the system? Remember to measure from the showerhead to the tank.