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Technical Library: Gasfitting


Installing the wrong gasfitting materials

Installing the wrong gasfitting materials or the right materials incorrectly, can result in not only poor workmanship issues, but also lead to disastrous outcomes.
It is important to remember the over aching requirements of AS/NZS 5601 section 2—mandatory performance requirements for gas installations.

Of particular concern is the installation of oven flexi hoses.

The use of domestic flexi hoses in ommercial installations does not meet installation compliance requirements, unless the manufacturer states the hose is suitable for this application.

The following information details key points regarding flexi hose installation.

Remember: when the word shall is stated in this standard it means that the requirement is mandatory for compliance.

Section 2 of AS/NZS 5601 details that the hose must be a suitable grade and size for the installation, meeting durability requirements and providing the correct gas flow to the burner.

Some key points are:

[ 2.3.1 ] : Materials, fittings and components used in any gas installation shall be suitable for use with the:

a. type of gas being conveyed;

b. the pressure to which they may be subjected to under both operating and fault conditions; and

c. the environment in which they are installed.

[ 2.4.1 (c)] : Consumer piping shall be designed and installed to:

c. avoid damage by corrosion, stress or other means.
This includes the possibility of crushing by the appliance.

Where these points arise these requirements must be met. You must ensure the correct hose is used in each installation.

Just because you can buy it, doesn’t mean it is right for the installation. If in doubt ask the manufacturer for the specifications on the hose to be sure it is the right one for the job.

Commercial appliances often subject the hose to higher temperatures and are more frequently moved for cleaning. The hose is likely to suffer damage if it is not protected from strain or from being damaged by the appliance itself.

As you will see in the images above the hoses have suffered major damage due to the two effects that have been described; movement stress and appliance heat damage.

AS/NZS 5601.1 2013 is now more prescriptive in regards to the installation of a cooker with a flexible hose assembly. You will find specific reference to this in section

You will also see that section 5.9.7 and 6.10.2 detail information regarding commercial catering equipment.

It is important to follow the manufacturer’s instructions including the use of a flexible connection.

Ensure the flexible hose is suitable for the gas type, pressure, flow (right size) and environment (subject to heat, cooking fats etc.). provides further information regarding under cooker connection.

Where a domestic cooker is involved and connected
to consumer piping using a hose assembly, the hose assembly used shall be certified to AS/NZS 1869 Class B or Class D.

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Phone: 0800 743 262, Email:, Post: PO Box 10655, The Terrace, Wellington 6143
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