Defining setpoint temperature and RH schedules

Schedules Timing Model Option

Operation of heating and cooling equipment is defined by selecting a Schedule under the Heating, Cooling and Operation headers on the HVAC tab.  These schedules are used to generate both the heating/cooling availability schedule and the temperature setpoint schedules used in the simulations. Schedule values greater than 0.5 indicate the system is in full operation controlling temperature to the main heating/cooling setpoint, values between 0 and 0.5 indicate the equipment in setback mode and values of 0 indicate that the equipment is switched off. See Table below.

 

Value

Heating/Cooling Equipment Operation

0

Equipment is off

> 0.5

Equipment is controlled using the main temperature setpoint data (Activity tab)

0 < Value <= 0.5

Equipment is controlled using the setback temperature setpoint data (Activity tab)

Notes

  1. When using 7/12 Schedules, for 0.5 read 50% etc.
  2. When using 2-Single period profiles with 7/12 Schedules to generate temperature setpoints the 'Off' periods are modelled using setback temperatures, i.e. the system is not switched off. If you wish the system to switch off outside main heating/cooling hours use the 3-Custom profile type.
  3. If the setback temperature set does not appear to affect results, this may be because the heating/cooling operation schedule selected uses only 0 and 1, not the 0.5 required to access setback temperature (see table above).

Typical Workday Timing Model Option

You can define the operation of heating and cooling equipment by entering Typical workday start and end times and seasonal operation under the Heating and Operation headers on the HVAC tab.  

 

This data is used to generate both the heating/cooling availability schedule and the temperature setpoint schedule used in the simulations.

 

The equipment is switched on between the On and Off times (8am and 6pm in the example below).  During this time the equipment is controlled using the main temperature setpoint (Activity tab). At other times and during weekends the equipment is controlled using the setback temperature setpoint. Weekends are defined on the Activity tab at the building level under Occupancy by setting the number of working days per week.

 

The Seasonal control data allows you to set times when the equipment is switched off altogether.  For example the heating system data shown below indicates that the heating system will be switched on during the winter only and switched off in the summer.

 

 

See also the Timing, Schedules, Profiles and Holidays Tutorial