Low Water Pressure

Lack of water pressure is frustrating as it slows the cycle times on appliances such as washing machines, dishwashers, reticulation and hot water units.

Low water pressure can be caused by;

  1. Supply pressure from the mains
  2. Pipe sizing
  3. Restriction
  4. Burst in system allowing water to escape
  5. Height and distance
  6.  Hot water units
  7. Flow restrictors

And can often be combinations of the above .

1. Incoming pressure

A pressure and volume test at the incoming water source (usually the water meter) will tell us what the available pressure and volume to the property is.

  • Water Corporation is obligated to deliver a minimum of 20 litre/min volume at meter
  • Water meters at device 150kpa (15m head)

Fremantle for instance will typically deliver 350kpa – 45 litres per min.

Often we get complaints of insufficient water pressure to retic and second storey bathrooms.

What is the solution – If I have low water pressure from the mains?

If you are getting above 150kpa at the meter, the Water Corporation (Western Australia) will not be obligated to help you.

What we offer to remedy the situation is to increase the pressure by pumping up the delivery pressures.To do this legally we create a water storage tank and pump system that guarantees a pre-set pressure to the system.

While pressure and volume are separate concepts, they will affect each other i.e.; water pressure from 150 - > 450kpa will increase water delivered at the end of the pump by 100%.

Typically the cost of this sort of system ranges from $5000 to $6000 and depends on size and structure of the tank, if above or below ground.

Tank should be a min of 1000 litres.

Example locations where this may be required: the ‘hill’ East Fremantle

If you would like us to help with this problem, please contact us now.  

2. Pipe sizing

Typically in Western Australia pipe work is undersized, compared to the rest of Australia. Most houses have the entire run of hot pipe work in 15mm copper/ (1/2”).

Over long runs and lots of bends, the pressure diminishes at point of delivery. In new constructions, correctly sized hot lines remedy any shortfall in pressures.

It is harder in existing houses where retro fitting large pipe work is not always and option.

What is the solution – to poor volumes?

  1. Upgrade the pipe size
  2. Upgrade the pressure (via pumping method)

If you would like us to help with this problem, please contact us now.

3. Restrictions

Water volume can be lost by restrictions in the line, kinks, tight bear valves, objects in the pipe and distance causing resistance on the water delivery.

Typically, the pressure ‘starts good’ then drops off. As we know, pressure is constant and the drop is caused by greater volume of water on one side of the obstruction.

The water therefore spreads out in the pipe and loses pressure at delivery.

Too many bends in valves and long distance also cause the same issues.

What is the solution?

Locate and remove the restrictions. Often this involves replacement of sections of pipe work to by pass the fault.

If you would like us to help with this problem, please contact us now.  

4. Bursts

Water escaping from our systems also will have the effect of lowering the pressure, i.e. – losing 2 litre/min into the ground drops the pressure.

What’s the solution

  • Pressure test the system
  • Locate and repair leak

If you would like us to help with this problem, please contact us now.

5. Heights

The higher water goes the lower the water pressure. It’s called gravity!

For every 1m of height you will lose 10kpa. i.e.; If you have 150kpa coming in and if you try to raise it 10m you will have lost 100kpa in pressure.

What’s the solution?

  1. Pumping (as per the previous solution)
  2. Make up tank which is a storage tank on top of the roof, attic or ceiling space which stores water and allows water gravity to deliver the water. This solution requires good pipe sizing the higher the tank the greater the pressure.

If you would like us to help with this problem, please contact us now.

6. Hot water units

Some hot water units restrict the flow of ‘hot’ water, they do this to allow more time for the water to stay in contact with the heat source.

Examples of this are;

Bosch P or H 10 gas – 10 litres a min
Super x Electric 6 litres a min

What is the solution?

A pump is not going to help.

The solution is a mains pressure hot water unit i.e. Aquamax gas storage.

If you would like us to help with this problem, please contact us now.

click here for some plumbing tips
Click here for a special offer for new Fremantle residents

Sign up for News & Offers

* Required




Captcha Image