Sequence of Operation
FORM
TABLE 5-6 HEAT STAGE ON WHEN SPACE INPUT SATISFIED
OAT VS OAT COMFORT ZONE | SAT VS SAT COMFORT ZONE | ECON OPERATION | HEAT STAGE | COMP STAGE |
BELOW | ABOVE | OPEN | LEAVE ON* | - |
BELOW | BELOW | - | LEAVE ON | - |
BELOW | WITHIN | - | LEAVE ON | - |
ABOVE | ABOVE | - | TURN OFF | TURN ON |
ABOVE | BELOW | OPEN | TURN OFF | - |
ABOVE | WITHIN | - | TURN OFF | - |
WITHIN | ABOVE | OPEN | TURN OFF | - |
|
|
|
|
|
WITHIN | BELOW | OPEN | TURN OFF | - |
WITHIN | WITHIN | - | TURN OFF | - |
|
|
|
|
|
Sequence of Operation
Tables
•SAT COMFORT ZONE – the temperature be- tween the “COMFORT VENTILATION LOWER SETPOINT” minus 1.0° F and the “COMFORT VENTILATION UPPER SETPOINT” plus 1.0° F.
•OAT COMFORT ZONE - the temperature be- tween the “COMFORT VENTILATION LOWER SETPOINT” and the “COMFORT VENTILA-
TION UPPER SETPOINT”.
•OAT – Outdoor Air Temperature.
•SAT – Supply Air Temperature.
•ECON OPERATION – Economizer damper will open to BRING SAT into the SAT COMFORT ZONE.
Conditions of Operation
•In order for compressor operation “COMFORT VENTILATION FOR COOLING ENABLED” must be enabled.
•In order for heat stages to operate “COMFORT VENTILATION FOR HEATING ENABLED” must be enabled.
•Economizer operation will occur with either, or both, “COMFORT VENTILATION FOR COOL- ING ENABLED” or “COMFORT VENTILA- TION FOR HEATING ENABLED” enabled.
EXCESSIVE SAT (SUPPLY AIR TEMPERATURE) CONTROL
This feature is only available on Constant Volume units. On a Constant Volume unit, the compressors and heat stages are control by the space temperature only, either by thermostat or zone sensor. As long as the room device is calling for cooling or heating the compressors or heating section does not control the actual temperature of the supply air leaving the unit. The enabling of this feature adds a means to prevent low or high supply air temperatures from being delivered to the conditioned space.
Cooling
The following System Parameters must be programmed:
“SUPPLY AIR TEMP LIMIT FOR COOLING ENABLED”- must be enabled using Parameter 14 under the PROGRAM key on the Simplicity control board or under the COOLING SETUP tab in the Simplicity PC software package.
“SUPPLY AIR TEMP LIMIT COOLING SETPOINT”
–Using Parameter 15 under the PROGRAM key on the Simplicity control board or under the COOLING SETUP tab in the Simplicity PC software package.
If a single compressor is energized the control will monitor the supply air temperature and respond as follows:
82 | JOHNSON CONTROLS |
