Rheem W2W Series Owner's Manual And Installation Instructions page 6

ABOUT YOUR WATER HEATER
TO TURN OFF THE WATER HEATER

Switch off the electrical supply at the isolating switch to the water heater

Close the cold side and hot side water isolation valve at the inlets to the water
heater.
TO TURN ON THE WATER HEATER

First, ensure the water is connected to storage tanks, the system is filled with
water and all valves between the tanks and the water heater are open

Open the cold side and hot side water isolation valve fully at the inlets to the
water heater.

Switch on the electrical supply at the isolating switch to the water heater.
Note: The water heater may not turn on immediately when it is first switched on,
if it is switched on within 20 minutes to 2 hours of it having been switched off at
the isolating switch, or the heat pump has just completed a heating cycle. The
water heater will wait until the conditions for start-up are favourable in order to
protect the compressor from damage. This may take up to 20 minutes to 2 hours.
The auxiliary booster will operate instead of the heat pump if the heat pump is in
fault or sufficient energy is not available from the chiller.
HOW DO I KNOW IF THE WATER HEATER IS INSTALLED CORRECTLY?
Installation requirements are shown on page 19. The water heater must be
installed:

by a qualified person, and

in accordance with the installation instructions, and

in compliance with Standards AS/NZS 3500.4, AS/NZS 3000 and all local
codes and regulatory authority requirements.
In New Zealand, the installation must also conform with Clause G12 of the New
Zealand Building Code.
DOES THE WATER CHEMISTRY AFFECT THE WATER HEATER?
This advice relates to the cold water side and hot water side of the heat
pump water heater.
The water heater is suitable for most public water supplies, however some
water chemistries may have detrimental effects on the water heater, its
components and fittings. Refer to "Water Supplies" on page 14. If you are
not sure, have your water chemistry checked against the conditions described
on pages 14 to 15.
6