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Maintenance: Hot Water Systems (HWS)


In this chapter we examine hot water systems, both shared and individually owned. We also discuss preventative maintenance.

Legislation – Strata Titles Act

Click on Legislation above, to view strata title legislation and hints.

Legislation – Community Titles Act

Click on Legislation above, to view community title legislation and hints.

Common Problems

The following pictures illustrate some typical types of HWS installations at units along with some common problems.

Gas Storage: This installation is owned by the Corporation and serves four units. It is gas fired with a flue through the common roof.

Water meters (on adjacent wall) are used to measure the amount of hot water used by each resident. This is then used by the gas company for billing purposes.

Some common problems include

  • the gas pilot flame blowing out
  • leaking pressure relief valves

Electric: This installation shows two separate hot water services serving two separate units, the law designates that they are the respective owner’s responsibility to maintain. They heat continuously as they are too small to store heat overnight on J tariff (off peak) electricity.

Some common problems include

  • leaking tank
  • leaking pressure relief valves

Preventative Maintenance – anode replacement

Replacing Owner or Corporation’s hot water systems (HWS) is both expensive and inconvenient. There is an answer to extending the life of storage type units

Sacrificial anodes are built into most HWS to prevent corrosion. These anodes work by corroding before the lining of the tank does. The anode is more electrochemically reactive than the lining of your tank and consequently the lining is left untouched.

To ensure the continued protection of the lining of your HWS the anode needs replacing approximately every three (3) years.

Sometimes the HWS is forgotten until the shower runs cold or the tank rusts through and floods.

The cost of a standard anode replacement is approximately $200 (depending on the age of the HWS and level of corrosion) which is cost effective considering the cost of replacing your HWS.

The cross section below shows the elements of a typical hot water storage system. The anode is inserted and removed through the top of the storage cylinder.

Best Practice

A responsible officer or the manager to make a note in their diary to have your group’s licenced plumber check/replace the common anode in all shared hot water systems every 3 years, or as recommended.

Gas instantaneous: Units in this group are served by gas fired instantaneous water heaters. They are the owner’s responsibility to maintain.

These heaters only heat when water runs through them. In the model depicted the gas is controlled by a rubber diaphragm.

Some common problems include

  • pilot light blowing out in exposed conditions
  • diaphragm perishes – no hot water
  • scorching of eaves above the heater
  • replacement heaters require replumbing, new electrics as well as compliance with new regulations on placement

Preventative Maintenance – instantaneous

One of the most common parts to fail is the rubber diaphragm which turns the gas on and off. Over time this perishes and the water becomes cooler and eventually fails to heat.

We suggest your HWS checked be checked by a qualified person plumber. Also we suggest a general clean and service every two years.

Solar hot water heating: The photograph below shows a typical solar hot water panel installation.


The owner requires the Corporation’s approval to install. See Policy suggestion under the Meeting section.

Best Practice

Organize a qualified plumber to check your HWS. This can help extend the life of your HWS by identifying problems such as corrosion, pressure relief valves etc.


The following tools may assist in the maintenance and replacement of hot water systems at your Corporation.

Hot water service types

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Electric hot water service

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Gas hot water service

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