Getting more water pressure in the shower from Low Pressure Hot water Cylinder ?

[mrsaneperson]

Well i have a tenant who has just moved in and is complaining about the low water pressure particularly from the shower head. So i went over and took a look , cleaned out the nozzles on the shower head itself which made a small difference. I also checked the water flow from the kitchen hot water tap it is 3Litres a minutes which is about the same as my own home.
Could there be a blockage in the pipes somewhere?

It is frustrating when plumbers routinely tell you that the only solution is to upgrade to a Mains Pressure Cylinder without even considering their could be a fault somewhere. Mains Pressure Cylinders are around 2k that is an ouch for me ...And it may very well be unnecessary since i know the water pressure for this particular property has dropped around a year ago as the previous tenant back then told me about it but i could not rectify it.

I have gone and purchased from eBay the ""Fire Hydrant Shower Head"" supposedly designed to fix the problem:

https://www.amazon.com/Best-Shower-Head-Water-Pressure/dp/B00WXPGCSE

[jimO]

could the shower mixer be blocked?

[mrsaneperson]

Its possible but the low hot water pressure i am getting is from all faucets so i am thinking it more likely to be something to do with the HWC.

Replacing the mixer with one that has bigger chambers would probably also help . Anyone know a good one ? I am told Methven do one.

[sparxNZ]

If you want to check if you've got a restriction somewhere between the header tank and the output from the cylinder you'll need a tee and a pressure gauge. Then you check the static pressure and compare it to the operating pressure at the cylinder output.
IMO don't bother. There's probably some build up of muck somewhere either in the cylinder or in the output pipe before it splits up to the faucets and shower and it would take too long to find it and clear it out. You could just open all the hot taps and blast a bit of compressed air into the cylinder input but that's time and effort as well - and you'd want to know what you're doing or you might end up splitting old pipes with the pressure.
I had an old house with a low pressure system (both hot and cold) and I just bought two el-cheapo booster pumps and put one on the hot water cylinder output and one on the cold circuit output from the header tank.
It worked superbly and cost about $250 all up. Only issues with it were that there was a trick to getting both pumps to come on when you open the shower mixer and that the system pumped so much water it would empty the header tank if you took a really long shower because the ballcock filling the tank flowed less than the pumps, then you'd get an air lock in the pipes.
Anyways, the long and the short of it is that cheap and nasty booster pumps are a $250 solution to a $2000 problem.

[Bob Kane]

Can you check the water flow of the hot water in the shower?
It should match the kitchen tap hot water flow.
Try measuring it as is and then with the shower head removed.
Also check the water flow on every other hot tap.
You might see a pattern emerge which could point to a particular pipe has a blockage.

[jimO]

are the pipes old galv?

[mrsaneperson]

The pipes are plastic, the hot water flow looks to be around the same from all faucets .

As regards adding pumps inline that would work but I've heard they're a bit noisy since every time any faucet is opened the pump will come on.

I once had a similar problem to this immediately after a shower renovation took place and a new shower mixer was installed .It was an existing low pressure HWC and after the shower reno the plumber who had done the install insisted that the trickle coming out of the shower head - which previously was a good flow - was due to the fact i needed to upgrade the HWC to a mains pressure one for an extra $2.5k.
I asked how could this be since the shower had performed well up until the time he had done the reno and only afterward had turned into a dribble. He then tried to blame the shower mixer which i had supplied him, but when i rang up the manufacturer Aquatica based in Auckland they said the mixer should be fine for low pressure cylinders and operated on a minimum of 65psi [i think that was the figure i recall].
""Has the plumber done a pressure test coming directly out of the shower faucet?" they asked.
He hadn't. After the pressure test measurement which was found to be way below the 65 psi he admitted to making a mistake [deliberate? ] as he said he had found a pressure reducing valve he'd installed in the system to be to high and a wrong component which must have been picked up from the plumbers merchants from a wrong box.

Fixed the mistake, and all good....... Of course, no apology. But saved 2.5k

[Perry]

I agree that assessing the pressure reducing feed valve and the pressure relief valve (if fitted) is a good start. The feed valve is the usual culprit. Distance differences between outlets could be factor despite that volume/flow tests at various outlets seem to indicate all is well.

[Keithw]

The right shower head can make a huge difference.
I have had tenants swap heads with ones that are supposed to pulse or whatever & the flow rate has been dismal due to the low pressure.
Putting back a head with fine jets has at least made the shower usable again.

The other thing to watch for is the internal diameter of the flexible hose if using a hand held shower.
The majority of hoses are designed for high pressure & have a small internal diameter. Low pressure hoses have a much bigger internal diameter (sometimes called full bore). this allows a higher volume to be delivered to the head at low pressure, giving better jets with the right head.

As Perry has noted, the NEFA pressure reducing valves can sometimes need readjusting, getting it just right can be a bit of trial & error depending if you have a vent pipe or a relief valve.
With a vent pipe you can adjust the valve until the water dribbles out the top then back off a little to allow for expansion of a full tank from cold to hot.
With a relief valve its a bit harder, adjusting until the relief valve opens is pushing the system to its limit, so it is better to increase a little at a time.

Old diaphrams in NEFA valves can also cause you problems. I had one that was working fine until i turned off the main supply, at which point the back pressure split the diaphram !!
In my experience plumbers dont like to replace diaphrams & seating washers as they take a bit of adjustment, they normally insist that the whole NEFA valve needs to be replaced ($200 +), but diaphrams and seating washers are easily obtainable from Bunnings & various plumbing suppliers.

[Meehole]

When I've been a tenant, I always check the shower for pressure and will NEVER EVER rent a place that has low water pressure. Freeze your bits off in the shower and still can't get fully wet.

[mrsaneperson]

When I've been a tenant, I always check the shower for pressure and will NEVER EVER rent a place that has low water pressure. Freeze your bits off in the shower and still can't get fully wet.

Agreed, nothing beats a nice hot shower with great pressure . I love the ones at my local gym which have great pressure and much better than my home one.

The "Fire Hydrant"" shower head i purchased from eBay has now arrived so over the next week or 2 i will endeavour to replace the old head and see if it performs any miracle. I'm still waiting for another part to arrive for a damaged shower waste top for the same property.

[mrsaneperson]

The "Fire Hydrant"" shower head definitely worked and has fixed the problem, the overall volume of spray seems much better ; i took before and after pics of the water flow and you can see their is a big difference. Tenant is happy too i rang him a few weeks later to check the verdict.

Here is the original old one:

https://www.dropbox.com/s/15zwdwuy3zjdf2e/original%20cruddy%20shower%20head.JPG?dl=0

Here is the Fire Hydrant new one:

https://www.dropbox.com/s/srdd5c50940muk5/fire%20hydrant%20shower%20head.JPG?dl=0

[morymorya]

When I've been a tenant, I always check the shower for pressure and will NEVER EVER rent a place that has low water pressure. Freeze your bits off in the shower and still can't get fully wet.

You are right. I used to live in areas with low water pressure. What upset me the most is that the shower that should have been pleasant has become bad. Later, I had to deal with this problem with Google and then purchased a high pressure shower head according to other people's suggestions, the problem has been solved.

[hufty]

Methven do a venturi shower mixer. My plumber says only one for low pressure, also make sure basin mixers have large flexi hoses as it makes a huge difference