Rheem 310 Owner's Manual And Installation Instructions page 7

MAINS PRESSURE
The water heater is designed to operate at mains pressure by connecting directly to the mains water supply.
If the mains supply pressure in your area exceeds that
fitted. The supply pressure should be greater than 350 kPa for true mains pressure operation to be achieved.
A minimum water supply pressure of 200 kPa is required to enable the heat pump circulator and heat pump
system to operate effectively.
TIMER CONTROL
A timer can be installed in the electrical circuit to the water heater. The timer must be weatherproof if it is
installed outdoors.
It may be desirable for the water heater not to operate between certain hours, such as during the peak
period when connected to a Time of Use electricity supply due to a more expensive tariff rate applying. A
timer will affect the operating times of both the heat pump circuit and the booster heating unit.
Note: The 551 310 model heat pump water heater is recommended for connection to a minimum 16 hour per
day power supply. If there is a risk of freezing conditions, the electrical supply to the water heater should not
be switched off, otherwise damage could result (refer to
TO TURN OFF THE WATER HEATER
If you plan to be away from home for only a few nights, we suggest you leave the water heater switched on.
If it is necessary to turn off the water heater:
Switch off the electrical supply at the main isolating switch to the water heater.
Close the cold water isolation valve at the inlet to the water heater.
Note: If there is a risk of freezing conditions, the electrical supply to the water heater should not be switched
off, otherwise damage could result (refer to
TO TURN ON THE WATER HEATER
Open the cold water isolation valve fully on the cold water line to the water heater.
Switch on the electrical supply at the main isolating switch to the water heater.
Check and if required reset the timer, if one is installed.
The heat pump may take up to 30 seconds to 5 minutes to commence operating when the power supply is
switched on. The heat pump will only operate when the water in the storage tank requires heating, the heat
pump compressor is cool and power is available at the water heater.
If the ambient air temperature is below the minimum operating temperature of 5°C and the system calls for
heating, the heat pump will commence operating and after a period of time, heating will switch from the heat
pump to the booster heating unit.
If the ambient air temperature is below 0°C and the system calls for heating, the heat pump will not operate
and the booster heating unit will operate instead.
When the heat pump is operating, the system may switch to the booster heating unit if it detects that the
ambient air temperature is below the minimum operating temperature of 5°C. It may also switch back to heat
pump operation from the booster heating unit if it detects the ambient air temperature has moved back to
within the heat pump‟s operating temperature range.
Note: The heat pump may not turn on after having just completed a heating cycle and more hot water is
drawn from the water heater, or if power was switched off whilst the heat pump was operating. The heat
pump will wait at least 5 minutes, and until the compressor has cooled down and the conditions for start up
are favourable, in order to protect the compressor from damage. This may take up to 20 minutes from the
last heating cycle.
shown on page
"Freeze Protection"
"Freeze Protection"
on page 4).
7
ABOUT YOUR WATER HEATER
20, a pressure limiting valve must be
on page 4).