18
CONNECTIONS – PLUMBING
IMPORTANT:
When installing a new water heater to an old or existing system, it is a requirement that the system
and its equipment be thoroughly inspected and if necessary, drained and flushed with clean fresh water, before the
new water heater is connected. Failure to do this may cause blockages and/or damage to the water heater which is
not covered by warranty.
IF THERE IS ANY DOUBT ABOUT THE SYSTEM, DRAIN AND FLUSH AS A PRECAUTION.
CONNECTION SIZES
147 On/Off
147 Hi/Lo
Inlet water connection
RP1¼/32
RP1¼/32
Outlet water connection
RP1¼/32
RP1¼/32
Relief valve connection
RP¾/20
RP¾/20
Gas inlet
RP¾/20
RP½/15
All plumbing work must be carried out by a qualified person and in accordance with the National Plumbing
Standard AS/NZS 3500.4 and local authority requirements.
All gas work must be carried out by a qualified person and in accordance with the Australian Gas Installations
Standard AS/NZS 5601 and local authority requirements.
WATER INLET AND OUTLET
All pipe work must be cleared of foreign matter before connection and purged before attempting to operate the
water heater. All olive compression fittings must use brass or copper olives. Use thread sealing tape or approved
thread sealant on all fittings.
An isolation valve and non-return valve must be installed on the cold water
line to the water heating system. An acceptable arrangement is shown in the
diagram opposite for a water heating application.
A disconnection union must always be provided at the inlet and outlet on the
water heater to allow for disconnection of the water heater.
Do not reduce the pipe work size and water heater water connections without
allowing for friction loss which will occur. Low water flow will cause damage to
the water heater and system components.
GAS INLET
The gas connection is made at the right hand end of the water heater for 109 Models and at the inlet of the gas
control for 147 models. The pipe work must be cleared of foreign matter before connection and purged before
attempting to light the water heater. An isolation valve and disconnection union must be used to allow servicing and
removal of the water heater.
Refer to the Gas Installations Standard AS/NZS 5601 for the correct method of sizing the gas supply pipe to the
water heater.
WARNING:
Before pressure testing the gas supply system always isolate and disconnect the water heater after
the isolating cock to prevent the risk of serious damage to the gas control. Warranty does not cover damage of any
nature resulting from failure to observe this precaution. Refer to rating label for gas types and pressures.
Ensure the gas line is also purged at the union connection to the water heater. If this procedure is not followed, a
retry lockout may result on initial start up.
CAUTION:
Care is necessary when tightening fittings into the gas control. The gas control casting may crack if the
fittings are over tightened. Cracked castings are not covered under warranty. Damaged gas controls must be
replaced.
PIPE SIZES
The pipe sizing for water heating and mechanical heating systems should be carried out by persons competent to
do so, choosing the most suitable pipe size for each individual application. Reference to the technical specifications
of the water heater and local regulatory authority requirements must be made.
