“Economizer Minimum Position” Alarm
•The supply air temperature must be below the
“SUPPLY AIR TEMP ALARM SETPOINT FOR HEATING” set point and the following sequence of events have occurred:
–All the stages of heating must have been on for 10 or more minutes.
–The outdoor air is 20.0° F or more cooler then the “SUPPLY AIR TEMP ALARM SETPOINT FOR HEATING” set point.
–The economizer must be open more than 20%.
•If the above criteria is met
–The Simplicity Elite control will close the outdoor damper for ten minutes.
–After ten minutes, the Simplicity Elite control will read the supply air temperature.
–If the supply air temperature is above the
“SUPPLY AIR TEMP ALARM SETPOINT FOR HEATING”, the control will keep the outdoor damper closed and complete the heating cycle.
∗The Simplicity Elite control will declare an
“ECONOMIZER MINIMUM POSITION” Alarm and flash an Alarm Code 40.
–If the supply air temperature is not above the
“SUPPLY AIR TEMP ALARM SETPOINT FOR HEATING”.
∗The Simplicity Elite control will declare a “SUPPLY AIR TEMP ALARM FOR HEATING” Alarm and flash an Alarm Code 39.
–After the heating cycle is completed, the Sim- plicity Elite control sets the outdoor damper to its minimum position.
–In order to reset the above alarms power to the unit must be cycled on and off.
FORM
SAT ALARM FOR COOLING
When this feature is turned, on the Simplicity Elite control monitors the supply air temperature in the cooling mode and will generate an alarm if the supply air temperature goes above the set point, and if conditions are met, modifies the amount of ventilation air to keep the supply air temperature below this set point when all the cooling stages are energized. This feature can only be used on unit operating in the VAV mode.
In order to use this feature the following parameter must be programmed:
“SUPPLY AIR TEMP ALARM SETPOINT FOR COOLING” – must be set under the COOLING SETUP tab of the Simplicity PC software package.
•If “SUPPLY AIR TEMP ALARM SETPOINT FOR COOLING” is set to zero this feature is disabled. If not set to zero, then the setting be- comes the alarm set point.
•Set “SUPPLY AIR TEMP ALARM SETPOINT FOR COOLING” to the temperature you want to use for the alarm set point. The range is 1.0° F to 80.0° F in 1.0° F increments.
5
Sequence of Operation
“Supply Air Temp Alarm Setpoint for Cooling” Alarm
•The control will initiate a “SUPPLY AIR TEMP ALARM FOR COOLING” and flash an Alarm Code 38 if the following conditions are met:
–All the stages of cooling have been on for 10 or more minutes.
–The supply air temperature is 20 degrees above the “SUPPLY AIR TEMP ALARM SETPOINT FOR COOLING” set point for 10 minutes.
–The outdoor air is not 20.0° F or more warmer then the “SUPPLY AIR TEMP ALARM SETPOINT FOR COOLING” set point.
–The outdoor air damper is not open more than 20%.
•In order to reset the above alarm power to the unit must be cycled on and off.
JOHNSON CONTROLS | 97 |
