To edit the data associated with a setpoint manager, you first need to select it by moving the mouse cursor over it and then clicking the mouse button to select it. You can then access the edit dialog by right-clicking the mouse and selecting the Edit selected component option or alternatively, select the Edit selected component tool from the toolbar.
This is the name that you assign to the setpoint manager which should be unique. If the supplied name is not unique, the software will automatically append a backslash and number to ensure that there are no duplicate names.
There several different types of setpoint manager available. However only certain types of setpoint manager are available for different types of loop:
Scheduled setpoint managers are the simplest type of setpoint manager and work by placing a scheduled setpoint value at the point or connection in the loop at which the setpoint manager control line has been placed. This allows you to specify either a constant, a seasonal, or other time-varying scheduled reset control strategy.
The control variable can be one of:
Select a schedule whose values are to be used as setpoints on the node or node list. The schedule value for each time period is the setpoint for this type of setpoint manager. The schedule must have values that are in the appropriate units as defined in the previous field.
Warmest setpoint managers are available only in Generic and Dual Duct air loops. The warmest setpoint manager resets the cooling supply air temperature of a central forced air HVAC system according to the cooling demand of the warmest zone. For each zone in the system at each system timestep, the manager calculates a supply air temperature that will meet the zone cooling load at the maximum zone supply air flow rate. The lowest of the possible supply air temperatures becomes the new supply air temperature setpoint, subject to minimum and maximum supply air temperature constraints. The resulting temperature setpoint is the highest supply air temperature that will meet the cooling requirements of all the zones. When compared to a fixed cooling supply air temperature setpoint, this strategy minimises zone reheat coil energy (or overcooling) and central chiller energy consumption (if the chilled water temperature is also reset) at the cost of possible increased fan energy.
The type of variable that will be controlled. There is only one choice for this type of setpoint manager: 1-Temperature.
This is the minimum allowed setpoint temperature (in °C or °F). If the calculated setpoint temperature is less than this minimum, the setpoint is set to the minimum.
This is the maximum allowed setpoint temperature (in °C or °F). If the calculated setpoint is greater than this value the setpoint is set to the maximum. This value is also used as the setpoint temperature when none of the zones have a cooling load.
Coldest setpoint managers are available only in Generic and Dual Duct air loops. The coldest setpoint manager is used in dual duct systems to reset the setpoint temperature of the air in the heating supply duct. Usually it is used in conjunction with a Warmest Setpoint Manager resetting the temperature of the air in the cooling supply duct. For each zone in the system at each system timestep, the manager calculates a supply air temperature that will meet the zone heating load at the maximum zone supply air flow rate. The highest of the possible supply air temperatures becomes the new supply air temperature setpoint, subject to minimum and maximum supply air temperature constraints. The resulting temperature setpoint is the lowest supply air temperature that will meet the heating requirements of all the zones. When compared to a fixed heating supply air temperature setpoint, this strategy minimises central boiler energy consumption (if the hot water temperature is also reset or there are variable speed pumps) at the cost of possible increased fan energy (if there is variable volume control in the air system).
The type of variable that will be controlled. There is only one choice for this type of setpoint manager: 1-Temperature.
This is the minimum allowed setpoint temperature (in °C or °F). If the calculated setpoint temperature is less than this minimum, the setpoint is set to the minimum. This value is also used as the setpoint temperature when none of the zones have a heating load.
This is the maximum allowed setpoint temperature (in °C or °F). If the calculated setpoint is greater than this value the setpoint is set to the maximum.
This setpoint manager allows for controlling the minimum humidity level in multiple zones served by a central forced air HVAC system (air loop). This setpoint manager, together with humidistats which must be defined for the controlled zones, detects the air humidity level in multiple controlled zones served by the HVAC air loop and uses air/moisture mass balances to calculate an average supply air humidity ratio needed to maintain the zone relative humidity levels near their respective humidifying setpoints. The calculated humidity ratio is then used as the minimum humidity ratio setpoint for the designated setpoint node(s). A humidification component (e.g. humidifier) placed upstream of the setpoint node can then use the minimum humidity ratio setpoint to control humidification rate.
Note: This setpoint manager requires that humidistats are specified for the controlled zones.
This is the minimum humidity ratio (kg/kg) that is allowed by this setpoint manager. If the calculated setpoint humidity ratio is less than this value, then the setpoint is set to this minimum value.
This is the maximum humidity ratio (kg/kg) that is allowed by this setpoint manager. If the calculated setpoint humidity ratio is greater than this value, then the setpoint is set to this maximum value.
This setpoint manager allows for controlling the maximum humidity level in multiple zones served by a central forced air HVAC system (air loop). This setpoint manager, together with humidistats which must be defined for the controlled zones, detects the air humidity level in multiple controlled zones served by the HVAC air loop and uses air/moisture mass balances to calculate an average supply air humidity ratio needed to maintain the zone relative humidity levels near their respective dehumidifying setpoints. The calculated humidity ratio is then used as the maximum humidity ratio setpoint for the designated setpoint node(s). A dehumidification component (e.g. water cooling coil) placed upstream of the setpoint node can then use the maximum humidity ratio setpoint to control its moisture removal rate.
In the case of a chilled water coil which is used for both temperature and high humidity control, this setpoint manager works in conjunction with the coil controller to determine the supply air temperature required to meet both the temperature (sensible) and humidity (latent) load in the control zone.
Note: This setpoint manager requires that humidistats are specified for the controlled zones.
This is the minimum humidity ratio (kg/kg) that is allowed by this setpoint manager. If the calculated setpoint humidity ratio is less than this value, then the setpoint is set to this minimum value.
This is the maximum humidity ratio (in kg/kg) that is allowed by this set point manager. If the calculated setpoint humidity ratio is greater than this value, then the setpoint is set to this maximum value.
This setpoint manager allows for controlling the minimum humidity level in multiple zones served by a central forced air HVAC system (air loop). This setpoint manager, together with humidistats which must be defined for the controlled zones, detects the air humidity level in multiple controlled zones served by the HVAC air loop and uses air/moisture mass balances to calculate a supply air minimum humidity ratio based on a zone with the critical humidification requirement (i.e., a zone with the highest humidity ratio setpoint) to maintain the zone relative humidity levels near their respective humidifying setpoints. The calculated humidity ratio is then used as the minimum humidity ratio setpoint for the designated setpoint node(s). A humidification component (e.g. humidifier) placed upstream of the setpoint node can then use the minimum humidity ratio setpoint to control humidification rate. If a humidistat is defined for only one of the zones served by the air loop then this setpoint manager behaves in the same way as the Single Zone Humidity Minimum setpoint manager.
Note: This setpoint manager requires that humidistats are specified for the controlled zones.
This is the minimum humidity ratio (kg/kg) that is allowed by this setpoint manager. If the calculated setpoint humidity ratio is less than this value, then the setpoint is set to this minimum value.
This is the maximum humidity ratio (kg/kg) that is allowed by this setpoint manager. If the calculated setpoint humidity ratio is greater than this value, then the setpoint is set to this maximum value.
This setpoint manager allows for controlling the maximum humidity level in multiple zones served by a central forced air HVAC system (air loop). This setpoint manager, used in conjunction with one or more Zone humidistat objects, detects the air humidity level in multiple controlled zones served by the HVAC air loop and uses air/moisture mass balances to calculate the maximum supply air humidity ratio based on a zone with the critical dehumidification requirement (i.e., a zone with the lowest humidity ratio setpoint) to maintain the zone relative humidity levels near their respective dehumidifying setpoints. The calculated humidity ratio is then used as the maximum humidity ratio setpoint for the designated setpoint node(s). A dehumidification component (e.g., desiccant dehumidifier) placed upstream of the setpoint node can then use the maximum humidity ratio setpoint to control its moisture removal rate.
The use of this object requires that a Zone Humidistat object be specified with a dehumidifying relative humidity schedule for one or more controlled zones served by the HVAC air loop. If the Zone Humidistat is defined for only one of the zones served by the air loop then this Setpoint Manager performs as a Single zone humidity maximum setpoint manager.
In the case of a chilled water coil which is used for both temperature and high humidity control, this setpoint manager works in conjunction with a the controller associated with the Cooling coil - water object to determine the supply air temperature required to meet both the temperature (sensible) and dehumidification (latent) load in the control zone.
See object Controller:WaterCoil in the EnergyPlus Engineering Reference for a detailed discussion of how this is achieved.
The minimum humidity ratio (in kg/kg) that is allowed by this setpoint manager. If the calculated setpoint humidity ratio is less than this value, then the setpoint is set to this minimum value. The default value is 0.008 kg/kg.
The maximum humidity ratio (in kg/kg) that is allowed by this set point manager. If the calculated setpoint humidity ratio is greater than this value, then the setpoint is set to this maximum value. The default value is 0.015 kg/kg.
The Single Zone Minimum Humidity Setpoint Manager allows the control of a single zone minimum humidity level. This setpoint manager detects the humidity level in a control zone and, using air and moisture mass balance, calculates the supply air humidity ratio needed to maintain the zone relative humidity at or above a given setpoint. The calculated supply air humidity ratio is then used as the setpoint for the designated setpoint node. A humidifier component placed upstream of the setpoint node can then use the humidity ratio setpoint to control its moisture addition rate.
Note: This setpoint manager requires that a humidistat be specified for the controlled zone.
Click on the <Select zone> label and then click on the displayed ellipsis button to bring up the zone selector dialog. Select the zone for humidity control.
The Single Zone Maximum Humidity Setpoint Manager allows the control of a single zone maximum humidity level. This setpoint manager, together with a humidistat which must be defined for the controlled zone, detects the air humidity level in a single control zone and uses air/moisture mass balances to calculate the supply air humidity ratio needed to maintain the zone relative humidity at or below a given setpoint. The calculated supply air humidity ratio is then used as the setpoint for the designated setpoint node. A dehumidification component placed upstream of this node can then use the humidity ratio setpoint to control its moisture removal rate (e.g. water cooling coil).
In the case of a chilled water coil which is used for both temperature and high humidity control, this setpoint manager works in conjunction with the coil controller to determine the minimum supply air temperature required to meet both the temperature (sensible) and humidity (latent) load in the control zone.
Note: This setpoint manager requires that a humidistat be specified for the controlled zone.
Click on the <Select zone> label and then click on the displayed ellipsis button to bring up the zone selector dialog. Select the zone for humidity control.
The Outdoor Air Reset Setpoint Manager sets the supply air temperature according to the outdoor air temperature using a reset rule. The reset rule is determined by 2 points: the supply air setpoint temperature at the outdoor high temperature (SATOH) and the supply air setpoint temperature at the outdoor low temperature (SATOL). If the outdoor temperature is above the outdoor high temperature, the supply air temperature is set to SATOH. If the outdoor temperature is below the outdoor low temperature, the supply air temperature is set to SATOL. If the outdoor temperature is between the outdoor high and outdoor low temperatures, the supply air temperature is linearly interpolated between SATOH and SATOL.
An optional second reset rule may be defined.
The default Outdoor air reset settings for various loop types are:
| Loop Type | Outdoor Low Temp (°C) | Setpoint for Outdoor Low Temp (°C) | Outdoor High Temp (°C) | Setpoint for Outdoor High Temp (°C) | Comment |
| Air loop | 0 | 16 | 15 | 12 | |
| Hot water loop | 5 | 80 | 15 | 60 | |
| Chilled water loop | 15.56 | 12.22 | 26.67 | 6.67 | ASHRAE 90.1 Appendix G |
| Condenser loop | 0 | 33 | 15 | 29 | |
| DHW loop | 5 | 60 | 15 | 50 |
The type of variable that will be controlled. There is only one choice for this type of setpoint manager: 1-Temperature.
This is the setpoint (°C or °F) at the outdoor low temperature for the first reset rule.
This is the outdoor air low temperature (°C or °F) for the first supply air temperature reset rule. Generally, at this outdoor air temperature the supply temperature is at its maximum.
This is the setpoint temperature (°C or °F) at the outdoor high temperature for the first reset rule.
This is the outdoor air high temperature (°C or °F) for the first supply air temperature reset rule. Generally, at this outdoor air temperature the supply temperature is at its minimum.
This check-box allows you to define a second reset rule.
This is the schedule whose values indicate which reset rule to use. Schedule values of 1 indicate that the first reset rule will be used. Schedule values of 2 select the second reset rule.
This is the setpoint temperature (°C or °F) at the outdoor low temperature for the second reset rule.
This is the outdoor air low temperature (°C) for the second supply air temperature reset rule. Generally, at this outdoor air temperature the supply temperature is at its maximum.
This is the setpoint temperature (°C or °F) at the outdoor high temperature for the second reset rule.
This is the outdoor air high temperature (°C) for the second supply air temperature reset rule. Generally, at this outdoor air temperature the supply temperature is at its minimum.
The Single Zone Heating Setpoint Manager allows a component to be controlled based on the load required to meet the zone heating setpoint. This setpoint manager detects the control zone load to meet the current heating setpoint, zone inlet node flow rate, and zone node temperature, and calculates a setpoint temperature for the supply air that will satisfy the zone heating load for the control zone. This setpoint manager creates a variable temperature system.
The type of variable that will be controlled. There is only one choice for this type of setpoint manager: 1-Temperature.
The minimum supply air temperature (in °C or °F) that is allowed for this system (as set by this setpoint manager).
The maximum supply air temperature (in °C or °F) that is allowed for this system (as set by this setpoint manager)
Click on the <Select zone> label and then click on the displayed ellipsis button to bring up the zone selector dialog. Select the zone for single zone heating control.
It would ideally be possible to use both 11-Single Zone Heating Setpoint Manager and 12-Single Zone Cooling Setpoint Manager together on the supply side of a loop, however this would violate the EnergyPlus rule that each control variable cannot be controlled more than once for any node. However EnergyPlus does allow a special workaround for this situation. It is possible to add a 12-Single Zone Cooling Setpoint Manager on the supply side (as normal) and the 11-Single Zone Heating Setpoint Manager on the demand side as a special option. This allows a variable temperature heating and cooling system to be simulated.
The Single Zone Cooling Setpoint Manager allows a component to be controlled based on the load required to meet the zone cooling setpoint. This setpoint manager detects the control zone load to meet the current cooling setpoint, zone inlet node flow rate, and zone node temperature, and calculates a setpoint temperature for the supply air that will satisfy the zone cooling load for the control zone. This setpoint manager creates a variable temperature system.
See also note above on Combining 11-Single Zone Heating and 12-Single Zone Cooling Setpoint Managers.
The type of variable that will be controlled. There is only one choice for this type of setpoint manager: 1-Temperature.
The minimum supply air temperature (in °C or °F) that is allowed for this system (as set by this setpoint manager).
The maximum supply air temperature (in °C or °F) that is allowed for this system (as set by this setpoint manager).
Click on the <Select zone> label and then click on the displayed ellipsis button to bring up the zone selector dialog. Select the zone for single zone cooling control.
This setpoint manager is used to establish a supply air temperature setpoint for a central forced air HVAC system (air loop) based on the predicted sensible cooling loads and actual supply air mass flow rates for all zones served by the system. For all controlled zones in the air loop (i.e., zones with a thermostat object), the setpoint manager calculates an average supply air temperature that will meet the zone cooling loads based on the actual zone supply air mass flow rates (lagged by one time step). The calculated setpoint temperature is subject to the minimum and maximum setpoint temperature constraints specified by the user. When compared to a fixed cooling supply air temperature setpoint, this strategy may reduce zone reheat coil energy (or overcooling) and central chiller energy consumption (if the chilled water temperature is also reset) at the cost of possible increased fan energy.
The type of variable that will be controlled. There is only one choice for this type of setpoint manager: 1-Temperature.
The minimum supply air temperature (in °C or °F) that is allowed for this system. If the calculated setpoint temperature is less than this minimum, the setpoint is set to the minimum. The default value is 12°C.
The maximum supply air temperature (in °C or °F) that is allowed for this system. If the calculated setpoint temperature is greater than this value, the setpoint is set to this maximum value. The default value is 18C.
This setpoint manager is used to establish a supply air temperature setpoint for a central forced air HVAC system (air loop) based on the predicted sensible heating loads and actual supply air mass flow rates for all zones served by the system. For all controlled zones in the air loop (i.e., zones with a thermostat object), the setpoint manager calculates an average supply air temperature that will meet the zone heating loads based on the actual zone supply air mass flow rates (lagged by one time step). The calculated setpoint temperature is subject to the minimum and maximum setpoint temperature constraints specified by the user. When compared to a fixed heating supply air temperature setpoint, this strategy may reduce central boiler energy consumption (if the hot water temperature is also reset or there are variable speed pumps) at the cost of possible increased fan energy (if there is variable volume control for the air system).
The type of variable that will be controlled. There is only one choice for this type of setpoint manager: 1-Temperature.
The minimum supply air temperature (in °C or °F) that is allowed for this system. If the calculated setpoint temperature is less than this minimum, the setpoint is set to the minimum. The default value is 20°C.
The maximum supply air temperature (in °C or °F) that is allowed for this system. If the calculated setpoint temperature is greater than this value, the setpoint is set to this maximum value. The default value is 50°C.
This setpoint manager provides a temperature setpoint on a system node that is derived from a current ground temperature. The ground temperatures are specified in at site level and used during the simulation. This setpoint manager is primarily intended for condenser or plant loops using some type of ground heat exchanger.
When this SPM is selected the following other fields should be defined.
The type of variable that will be controlled. There is only one choice for this type of setpoint manager: 1-Temperature.
The minimum supply air temperature (in °C or °F) that is allowed for this system. If the calculated setpoint temperature is less than this minimum, the setpoint is set to the minimum. The default value is 11°C.
The maximum supply air temperature (in °C or °F) that is allowed for this system. If the calculated setpoint temperature is greater than this value, the setpoint is set to this maximum value. The default value is 16°C.
This setting specifies the type of ground temperature to be used by the setpoint manager. There are four options:
1-Deep - uses the Deep monthly temperatures defined at site level.
2-Shallow - uses the Shallow monthly temperatures defined at site level.
3-Building surface - uses the Monthly temperatures defined at site level.
Generally the deep ground temperatures are the most useful for a plant loop serving a vertical borehole ground heat exchanger.
This data provides a temperature offset that will be applied to the value of the ground temperature. If this value is zero, and the limits are met, then the resulting setpoint will be exactly the same as the ground temperature. The sign convention is that a positive value here will increase the resulting setpoint to higher than the ground temperature.