Rheem 953060DP Owner's Manual And Installation Instructions page 75

If the water heater is full of cold water, the fan will activate and heating will
commence unless the ambient air temperature is below the ambient sensor set
point, in which case the auxiliary boost will operate, if installed.
It is important to wait for five minutes after the heat pump has activated to ensure
it continues to operate and is functioning correctly.
Confirm correct pump rotation. Incorrect phase rotation will cause pump to not
start, and heat pump will trip (typically on high pressure). To correct phase
rotation, simply swap 2 pump wires.
Warning: Ensure power supply is isolated before swapping wires.
Confirm correct pump flow rate by checking temperature rise across the heat
pump heat exchanger shown on the display. Correct pump flow rate will produce
o
a temperature rise of between 4 and 6 C. Higher flow rate (lower temperature
rise) is acceptable within reason. Lower flow rate (higher temperature rise) is not
acceptable and the reason must be determined and rectified.
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 (if installed) will operate instead of the heat pump if the
ambient air temperature is less than the ambient sensor set point.
Explain to a responsible officer the functions and operation of the heat pump
water heater. Upon completion of the installation and commissioning of the water
heating system, leave this guide with the responsible officer.
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