-
Off: Set the output to the heat recovery wheel to off.
-
Max: Operate the energy recovery wheel at the maximum wheel speed. Turn off the Heat Recovery CloseOpen.
-
Hold: Hold the outputs at their current position.
-
Limited Max: Operate the energy recovery wheel at the Limited Max Speed. Turn off the Heat Recovery CloseOpen.
-
T Control: Modulate the energy wheel speed to control the Process Variable at the Setpoint. This mode is used for heating only because the heat recovery device can provide more heat than what is required to condition the space. During cooling, the heat recovery device cannot produce enough cold air to condition the space. When Heat Recovery Percent Cmd is 0%, the Heat Recovery OpenClose is set to Open. When Heat Recovery Percent Cmd is any other value, the Heat Recovery OpenClose is set to Close.
-
LL-T Control: Modulate the energy wheel speed to control the Low Limit Variable. The low limit variable is the air temperature leaving the energy wheel, and this mode is used to prevent the leaving temperature from dropping below freezing. If the Limit Variable is reliable, the module controls the output to maintain the Limit Variable at the Limit Setpoint. When Heat Recovery Percent Cmd is 0%, the Heat Recovery OpenClose is set to Open. When Heat Recovery Percent Cmd is any other value, the Heat Recovery OpenClose is set to Close.
Heat Recovery Suitability |
Cooling Mode |
Heating Mode |
PID Tuning Reset |
State |
---|---|---|---|---|
* |
Hold |
* |
Reset 1st PID |
T Control |
Hold |
Reset 2nd PID |
LL-T Control |
||
* |
Hold |
Reset 1st PID |
T Control |
|
Hold |
Reset 2nd PID |
LL-T Control |
||
None |
* |
* |
Off |
|
Cool |
Off |
Off |
||
Max |
Max |
|||
Hold |
Hold |
|||
Heat |
* |
Off |
Off |
|
Max |
Max |
|||
Limited Max |
Limited Max |
|||
Hold |
Hold |
|||
T Control |
T Control |
|||
LL-T Control |
LL-T Control |