Emerson VE User Manual

The following table is a list of features that should match the options installed with your unit and 

should not need to change during normal operation.

The temperature and humidity sensors can be calibrated by selecting this menu item. “SENSOR” 

shows the actual sensor reading or raw reading. “CALIBRATED” shows the sensor reading after the 

calibration offset has been added. The temperature sensor can be calibrated ±5 degrees Fahrenheit 

and the humidity sensor can be calibrated ±10% RH. When calibrating the humidity sensor, the value 

shown will always be % RH, even though absolute humidity control may be selected. If absolute 

humidity control is selected, the Normal Status Display will display the adjusted reading and may 

not agree with the relative humidity reading displayed while in calibration.

For systems that use a valve actuator for chilled water or glycol cooling, the actuator timing may be 

calibrated or adjusted through this feature. This is the time it takes for the valve to travel from full 

closed to full open. It is programmable from 0 to 255 seconds. The factory default time is 165 seconds 

and should not be changed unless the actual valve travel time is not correct. The full valve travel time 

is used by the control to determine the appropriate valve position. For example, if the valve travel 

time is 165 seconds and 50% cooling is being called for, the valve will open for 83 seconds to achieve 

50% open. To change the valve travel time, first enter the “CALIBRATE VALVE ACTUATOR” screen. 

The display will show the present period used by the control for valve actuator full travel. Press 

ENTER and adjust the time using the UP/DOWN arrows. When the correct time is displayed, press 

ENTER to store the new time in memory. 

The type of system control method used by the microprocessor can be selected from the front panel. 

The default setting is INTELLIGENT, which approximates the actions that a human operator would 

take to maintain precise, stable control. The control logic uses Artificial Intelligence techniques 

including “fuzzy logic” and “expert systems” methods to maintain precise, stable control and increase 

reliability by reducing component cycles. PROPORTIONAL is a standard control method that uses 

one gain factor (temperature sensitivity adjustment). TUNABLE PID (Proportional, Integral, and 

Derivative) uses three gain factors selected by the operator. PID allows precision tuning, but requires 

an experienced operator and seasonal adjustments. Note that if PID is selected, it is used for temper-

ature control while humidity will continue to use Proportional Control. For chilled water units with 

the optional Variable Speed Drive, Intelligent is required for proper operation. Refer to 5.0 - 

Response by Control Type—Advanced Microprocessor Controls for more details on types of 

control.

Heating

Yes or No

Humidifier

Yes or No

Dehumidifier

Yes or No

Humidifier Pan

Small or Large

Hot Gas Reheat

Yes or No

Heat Stages*

2 or 3

Dehumidification Stages

1 or 2

*If heat stage is set to 2 on a chilled water unit, the 
reheat 3 output is energized on a call for 
dehumidification.