Rheem MPi 551 Series Owner's Manual And Installation Instructions page 5

FREEZE PROTECTION
The water heater has a freeze protection system. The freeze protection system will protect the water heater
from damage, by preventing ice forming in the waterways of the water heater, in the event of freezing
conditions occurring.
If the ambient air temperature falls below 1°C and the heat pump is not operating, the system will operate the
circulator periodically. During this freeze protection cycle, the circulator will operate for thirty (30) seconds
and then rest for fifteen (15) minutes, before the cycle is recommenced. Water is circulated from the storage
tank through the heat pump circuit, to prevent freezing in the connecting pipe work and heat pump module.
The green LED will flash a series of four (4) flashes whilst the circulator is operating.
The water heater has NO WARRANTY for freeze damage if power is unavailable at the water heater.
Warning: In areas where the ambient air temperature may fall below 1°C, power must be available to the
water heater at all times to prevent freezing in the heat pump circuit.
HOW HOT SHOULD THE WATER BE?
The system controls (compressor, evaporator and fan) will
operate until a water temperature of 60°C is reached. If the
ambient air temperature is outside of the heat pump‟s operating
range, the water temperature is boosted automatically to 70°C
by the thermostatically controlled booster electric heating unit, if
heating is required.
To meet the requirements of the National Plumbing Standard
the temperature of the stored water must not be below 60°C.
HOTTER WATER INCREASES THE RISK OF SCALD INJURY
This water heater can deliver water at temperatures which can
cause scalding. Check the water temperature before use, such
as when entering a shower or filling a bath or basin, to ensure it
is suitable for the application and will not cause scald injury.
We recommend and it may also be required by regulations that
an approved temperature limiting device be fitted into the hot
water pipe work to the bathroom and ensuite when this water
heater is installed. This will keep the water temperature below
50°C at the bathroom and ensuite. The risk of scald injury will
be reduced and still allow hotter water to the kitchen and
laundry.
TEMPERATURE ADJUSTMENT
The thermostats controlling the heat pump and the booster heating unit are factory set and not adjustable.
WARNING
This water heater is only intended to be operated by persons who have the experience or the knowledge and
the capabilities to do so. This water heater is not intended to be operated by persons with reduced physical,
sensory or mental capabilities i.e. the infirm, or by children. Children should be supervised to ensure they do
not interfere with the water heater.
This water heater uses 240 V AC electrical power for operation of the control systems and the electrically
operated components. The removal of the access cover(s) will expose 240 volt wiring. They must only be
removed by a qualified person.
Do not use aerosols, stain removers and household chemicals near the water heater whilst it is
working. Gases from some aerosol sprays, stain removers and household chemicals are corrosive to the
materials used in the heat pump system.
Do not store swimming pool chemicals, household cleaners, etc., near the water heater.
Ensure the air flow, air inlet louvres and outlet grille are not obstructed in any way at any time.
ABOUT YOUR WATER HEATER
5
booster temperature setting
typical maximum temperature
from heat pump operation,
minimum recommended stored
water temperature
maximum recommended supply
temperature to bathrooms and
ensuites