Emerson VE Refrigerator User Manual


 
Component Operation and Maintenance, Checks and Adjustments
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7.0 COMPONENT OPERATION AND MAINTENANCE, CHECKS AND ADJUSTMENTS
7.1 System Testing
7.1.1 Environmental Control Functions
The performance of all control circuits can be tested by actuating each of the main functions. This is
done by temporarily changing the setpoints.
Cooling
To test the cooling function, set the setpoint to a temperature 10°F (5°C) below room temperature. A
call for cooling should be seen and the equipment should begin to cool. A high temperature alarm may
come on. Disregard it. Return setpoint to the desired temperature.
Heating
Reheat may be tested by setting the setpoint for 10°F (5°C) above room temperature. A call for heat-
ing should be seen and the heating coils should begin to heat. Disregard the temperature alarm and
return the setpoint to the desired temperature.
Humidification
To check humidification, set the humidity setpoint to a relative humidity 10% above the room humid-
ity. For infrared humidifiers, all the infrared bulbs should come on. For steam generating humidifi-
ers, you will immediately hear the clicks as it energizes. After a short delay, the canister will fill with
water. The water will heat and steam will be produced. Return the humidity setpoint to the desired
humidity.
Dehumidification
Dehumidification can be checked by setting the humidity setpoint to a relative humidity 10% below
room relative humidity. The compressor should come on. Return humidity setpoint to the desired
humidity.
Proportional Heating/Cooling/ Dehumidification
On Chilled Water, GLYCOOL
(Econ-O-Cycle, Free Cool, GLYCOOLING cycle) models, and models
with hot water reheat, the microprocessor is capable of responding to changes in room conditions.
These systems utilize either a two or three-way valve activated by a proportioning motor.
For cooling and dehumidification, the microprocessor will respond by positioning the valve propor-
tionally to match the needs of the room. Full travel of the valve takes place within the range of the
sensitivity setting. During dehumidification, full travel of the valve takes place within 2% RH.
For hot water reheat, the microprocessor will respond by positioning the hot water valve proportion-
ally to match the needs of the room. Full travel of the valve takes place within 1°F with each 0.1°F
resulting in 10% valve travel.
!
WARNING
Potentially lethal voltages exist within this equipment during operation. Observe all cautions
and warnings on unit and in this manual. Failure to do so could result in serious injury or
death. Only qualified service and maintenance personnel should work with this equipment.