Filter
Top Products
26
Condition 2
If the Δ (delta) (set point temperature minus the ambient indoor temperature) is greater than 5 ˚F, then the unit will switch
to electric heat, if available. The unit will continue to operate with electric heat until the heat demand is satised. Note that
the electric heat switches on after the Δ temp passes 5°F and the heat pump switches off. Also note that the electric heat
will run until the heat demand is satised. When another heat demand cycle is initiated, the heat pump will run unless the Δ
temp is greater than the electric heat threshold.
Automatic Emergency Heat
If the sealed system fails with a bad reversing valve or anything that causes the indoor coil to get colder than the indoor
ambient temperature:
1) If the indoor coil thermistor senses a 5 degree temperature drop as compared to the ambient temperature thermistor
and this lasts up to 5 minutes, the control board will switch the unit to electric heat and continue heating with it.
2) At this point, error code 15 is generated; heat pump failure. Indoor coil temperature lower than indoor ambient
temperature for 5 or more degrees for 5 consecutive minutes.
Note: It is Ok to continue to use the unit with the electric heater until the heat pump is repaired.
Electric Heat Operation in Cool with Electric Heat Units
When in the Heat mode, with and without Fan Mode Auto (Fan cycling):
If the indoor ambient temperature is below the Heat Demand Threshold (Heat Set Point minus 1.5 ˚F), turn on electric heat.
If Ambient is 0.3 ˚F above the Heat Set Point turn off the electric heat.
System Mode Auto
This mode provides automatic change over between cool and heat. The auto mode runs based on the room ambient
temperature vs. the Demand Thresholds. It is only available in Heat-Cool Unit.
Notes:
There is a buffer zone between the cool and heat set points where no heating or cooling is allowed to occur. It is critical
that the Cool Demand Threshold be greater than the Heat Demand Threshold by a minimum of 3° while in the Auto
System Mode. For example, if a user enters a value for the Auto Cooling Set Point that violates the minimum Δ 3° rule, the
Auto Heating Set Point will adjust accordingly.
Automatic Change Over Delay (Cool with Heat Units)
The change over delay ensures that any system heating or cooling over shoot does not trigger an opposite demand cycle.
The change over delay = 15 min. This timer blocks the opposite demand cycle from running until the timer expires. As an
example, if the last demand was a cool cycle, and another cool cycle is requested, the timer will not block the request.
However, if the last demand cycle was a cool cycle, and heat cycle is requested, the timer will block the request until the
change over delay is expired.
Heat Pump With Electric Heat Operation (Continued)