Coles Supermarket

Hard Water in Hot Water Systems


The continent of Australia often experiences drought conditions somewhere in the country at any one time.  The city of Perth has 26 different sources of water supply, and when the water resources are low more water is pumped from deep underground wells known as bores.  In recent years concerns and problems grew to such an extent that in Perth a task force was set up by the plumbing industry to help advise the state government’s water board of problems created by the poor quality hard water and diminishing water supplies.

New artesian water bores were drilled to keep up with water demand and were dragging up corrosive & high sediment water which has caused many problems including:

  • warranty claims on valve manufacturers due to clogged and corroded valves
  • plumbing suppliers warranty claims for pitted copper tubing and fittings
  • warranty claims on hot-water manufacturers due to heating element pitting and resulting failure
  • warranty claims on hot-water manufacturers due to calcium encrustation causing premature failure.

Dealing with the Problem

hard water hot water systemsR. Edmonds & Sons are an Australian company that design, manufacture and sell Edson water heaters.  They hold national contracts for design and supply of commercial hot water systems for many national corporations.

During the severe droughts in Western Australia many areas began experiencing very heavy, extreme, calcium scaling which coated heating elements and caused them to fail after only a few weeks of operation. When calcium scale builds up on heating elements it prevents the heat from being transferred to the surrounding water.  This in turn causes premature burnout and complete failure of heating elements.

Besides causing increased energy consumption and higher operational costs, the extremely high temperature reached can also cause damage to contacts on control thermostats and other components and this can cause motor burn out, which is very costly to replace.

So Edson installed sacrificial anodes, as standard, in all water heaters manufactured for WA, or for areas where a calcium scaling problem is known.  However after many premature failures of heating elements in new commercial hot-water systems supplied to the Coles Supermarket Group, it was found that the sacrificial anodes were not doing their job (they weren’t being attacked at all) and the heating elements were failing every 3-6 weeks due to scale build-up.  The Coles management team  was not impressed with the situation, and the Edson supply contract was in jeopardy of being cancelled unless a satisfactory solution to this problem was found.

The Solution

A local Edson contractor, who had had a Softer Water Conditioner in his own home for 7 years, recommended a unit be installed in the water heater system.  So to overcome the problem the Softer Water Conditioners were installed.

The Result

After continuing inspections it has been proven that the Softer Water Conditioners have overcome the problem.  In fact, the Edson stainless steel hot water system has been operational at one location for the past 11 years without the need to change the heating element at all during this time.

John Mangan, the Operations Manager of Edson Hot Water Systems was thrilled with the results they have had.  “Coles have specified the Softer Water Conditioners anti-scale system be installed on all new hot water system installations in Western Australia, coastal and known hard water areas. So we have installed numerous Edson Hot Water Systems with Softer Water Conditioners in a number of known hard water areas with fantastic results. We now offer them as a standard option to all who are purchasing an Edson Hot Water System, commercial or domestic.”