Sequence Of Operations; Energy Saver Mode - Rheem RUUD Iraining Manual

Sequence of Operations

E n e r g y S a v e r M o d e
Under no circumstances will the compressor and lower electric heating element
Start Sequence
1. If lower tank thermostat is less than 70ºF and upper tank thermostat is less than 75ºF, the
water pump and both elements are energized until the lower tank thermostat is 80ºF. This
Pre-Warm mode prevents the compressor system from experiencing excessively low
discharge pressure.
2. Compressor then starts as required when tank temperatures greater than 80ºF.
3. Evaporator fan starts – low speed.
4. Water pump starts and operates as required by tank temperature.
5. Upper heating element will remain off during the start sequence.
6. For the first 90 seconds no operational control will be polled for temperature values.
7. After 90 seconds of operation -
a. If ST (suction temperature) is below 47ºF, the evaporator fan is adjusted to high
speed operation and an additional 90 second delay is started. ST is not polled
until after the additional delay.
b. AS (ambient temperature) and WT (water temperature) leaving the condenser are
polled. If AS is less than 40ºF but not greater than 120ºF and WT is less than
132ºF, compressor operation continues. If not, lower electric heating element
operation is allowed.
Run Sequence
1. Fan speed will be held at the value determined during the Start Sequence.
2. Water pump will modulate speed as required.
3. Compressor operation continues until lower tank thermostat or condenser water
temperature limits are reached.
4. The upper electric heating element operation is locked out during the first 45 minutes of
each compressor run cycle.
5. The lower electric heating element operation is locked out while the compressor and/or
the upper heating element are operating in Energy Save Mode.
6. Lower electric heating element operation is allowed whenever compressor and upper
heating element operation is no longer required and the lower tank thermostat remains to
be satisfied.
7. If compressor is not utilized, evaporator fan will be de-energized.
8. Compressor, upper electric heating element, and lower electric heating element will
deenergize as operational temperatures are reached.
be allowed to operate at the same time.
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Heat Pump Water Heater