The Thermostat screen is used to group the spaces into heating/cooling zones and enter indoor temperature setting and schedule. Each conditioned space must be assigned to a zone.
Note: In the program interface the word zone is used as a synonym of thermostat.
Group of Spaces Served:
This input allows the user to create and edit heating/cooling zones. Click this field to open the Assigned Spaces to Thermostats window.
Assign Spaces to Thermostats:
This window will not appear if all the conditioned spaces have already been assigned to thermostats. To change the assignment you must first remove the space from the zone to which it was assigned by editing this zone. You may then re-assign this space to a new or existing zone.
Spaces not served by any thermostat:
This area contains the list of spaces that are specified as conditioned but are not yet assigned to a thermostat.
Spaces served by this Thermostat:
This area contains the list of spaces that are assigned to this thermostat.
To add a space to the zone, select it in the left panel and click > to move it to the right.
Click >> to move all the spaces in the left panel to the right.
Select a space in the right panel and click < to detach the space from this thermostat.
Click << to detach all spaces from this thermostat. You will not be allowed to close the window if no spaces are assigned to the thermostat (if the right panel is empty), because each thermostat must control at least one space.
Click OK to confirm your selection or Cancel to discard the inputs.
Select Yes for programmable thermostat and No for non-programmable. The selection applies to both heating and cooling settings (if any) and enables the input fields for setback temperature and time.
Is Area Heated:
Select Yes if this is a heating or heating/cooling thermostat, No otherwise. The following three input fields will be disabled if you select No.
- Occupied Heating Temperature: If you have a non-programmable thermostat, enter its set point here. If you have a programmable thermostat enter its higher setting (set up temperature).
- Unoccupied Heating Temperature: This field is disabled if you have a non-programmable thermostat. If you have a programmable thermostat enter its lower temperature setting (set back temperature).
- Unoccupied Hours per Day: This field is disabled if you have a non-programmable thermostat. If you have a programmable thermostat, enter the number of hours per day that the thermostat is set back to its lower setting.
Is Area Cooled:
Select Yes if this is a cooling or heating/cooling thermostat, No otherwise. The three following input fields will be disabled if you select No.
Occupied Cooling Temperature:
If you have a non-programmable thermostat enter its set point here. If you have a programmable thermostat; enter its lower setting (temperature when the building is occupied).
Unoccupied Cooling Temperature:
This field is disabled if you have a non-programmable thermostat. If you have a programmable thermostat; enter its higher temperature setting (temperature during unoccupied periods).
TREAT uses the following logic to generate the hourly schedule for space temperature based on specified occupied and unoccupied temperature and hours per day:
- Temperature for the first 8 “un-occupied” hours is centered on 2 am;
- Temperature for the second 8 “un-occupied” hours is centered on 2 pm;
- Temperature for the rest of the day is split between (a) and (b).
Occupied Heating Temperature – 70F
Un-occupied Heating Temperature – 60F
Un-occupied Heating Hrs/day – 12 hr.
Occupied Cooling Temperature –75
Un-occupied Cooling Temperature – 85F
Un-occupied Cooling Hrs/day – 8
Thermostat schedule may be manipulated by switching occupied and un-occupied temperature. For example, the cooling schedule above assumes that air conditioning is used during the day. If you want to specify night usage, you may set un-occupied temperature to 75F and occupied temperature to 85F. Specify heat pumps in both Primary Heating System and Air Conditioning sections. Entering a heat pump in the heating section only will not automatically account for cooling energy.
Unoccupied Hours per Day:
This field is disabled if you have a non-programmable thermostat. If you have a programmable thermostat enter the number of hours per day the thermostat is set at its higher setting. Use Delete button on Thermostats screen to delete a thermostat. All spaces that were served by the deleted thermostat will be available for a new assignment.
- TREAT will display a warning message when calculations are performed if an air conditioning system is entered on Heating/Cooling screen and some of the thermostats are heating-only. You may choose to ignore this message and proceed with calculations if you feel that your inputs are correct.
- TREAT uses the area of the spaces specified as conditioned on the Spaces screen to calculate all the area-normalized values such as heating and cooling slope. These outputs might be inaccurate if some of the zones are heating or cooling only.