Outdoor Air (Outdoor Air Equipped Models Only); Component Replacement, Charge, Evacuation, & Leak Instructions - Desert Aire ExpertAire LC Series Installation And Operation Manual

LV Only – The DHLV series electric duct heaters for LV units are externally mounted to the
supply air connection. The heaters are designed to be electrically connected to the
dehumidifier for single point power connection.
The DHLV heater is shipped independently of the dehumidifier. In most cases it is desirable
to locate the electric box of the heater on the same side as the dehumidifier electrical panel.
The heater has been designed to allow airflow in either direction such that it is possible to
position the electric box for the heater on the opposite side, however, the elements of the
heater must be located in the "blast" area of the blower. This is the area where the blower
wheel is visible.
Power and control wiring for the electric heater protrudes from the top of the dehumidifier
and must be securely connected to the electric heater terminals before providing power to
the unit.
A differential pressure switch is used as a safety interlock for proof of airflow. It is located in
the lower section of the LV. It is connected to static pressure sensors using the pressure
drop of the reheat condenser of the dehumidifier as proof of airflow. If the airflow drops
below the set point, the switch will open and prevent the heater from operating.
The static pressure sensors also allow an easy way to balance the airflow by using a
manometer to measure the static pressure drop of the reheat condenser. Refer to section
3.3 on air balancing for further details regarding the balance procedure. Be sure to replace
the heater differential pressure switch tube connections to these sensors when finished to
permit heater operation. The higher pressure is between the heat exchangers and the lower
pressure is in the blower compartment. The switch has an indication for high and low at the
tube ports.
5.4.9

Outdoor Air (Outdoor Air Equipped Models Only)

During the "occupied" mode the dehumidifier will energize the outdoor air damper and
exhaust fan terminal contacts. Desert Aire LC and LV Series dehumidifiers will operate in
the occupied mode only if the occupancy timer is set accordingly. See section 3.2 for
further outdoor air operation mode details.
5.5 Component Replacement, Charge, Evacuation, & Leak Instructions
Note that a new liquid line filter dryer will be required any time a refrigeration system is opened for
servicing. New dryer should be of the same capacity as the original or larger.
Recovery
When there has not been a major refrigeration system leak, the system will contain refrigerant. This
refrigerant must be either recovered to separate cylinders appropriate for the refrigerant type or
isolated in a portion of the refrigeration system that will not be open for service. In all cases you
must comply with Section 608 Refrigerant Recycling Rule of the Clean Air Act.
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Desert Aire - LC/LV Manual