Conditioning¶
| Setting | Description | Units | Default Value |
|---|---|---|---|
| Heating | |||
| Heating setpoint | |||
| Heating schedule | |||
| Heating limit type | |||
| Max heating capacity | |||
| Max heating capacity | |||
| Max heat flow | |||
| Heating CoP | |||
| Cooling setpoint | |||
| Cooling schedule | |||
| Cooling limit type | |||
| Max cooling capacity | |||
| Max cool flow | |||
| Cooling CoP | |||
| Mechanical ventilation | |||
| Mechanical ventilation schedule | |||
| Min fresh air per area | m3/s-m2 | 0.0003 | |
| Min fresh air per person | m3/s-person | 0.0025 | |
| Economizer type | NoEconomizer | ||
| Heat recovery type | None | ||
| Heat recovery efficiency (latent) | 0.65 | ||
| Heat recovery efficiency (sensible) | 0.70 |
Heating¶
This checkbox field defines whether or not this component is available to operate. If this field is unchecked, the Heating schedule field will be forced to the generic schedule name Off.
Heating setpoint¶
The temperature below which zone heating is turned on. Umi controls the temperature in the zone using a ThermostatSetpoint:DualSetpoint object. This would be for heating and cooling thermostat where both a heating and cooling setpoint can be scheduled for any given time period. The setpoint can be scheduled and varied throughout the simulation for both heating and cooling.
Note
In this version of umi, the heating setpoint can only be scheduled as a constant.
Heating schedule¶
The name of a schedule (ref: Schedule) that denotes whether heating is available. A schedule value greater than 0 (usually 1 is used) indicates that heating and humidification are available. A value less than or equal to 0 (usually 0 is used) denotes that heating and humidification are not available. If blank, heating and humidification are always available.
Note
Schedule for when the heating system is available. Winter only enables the heating system when the outdoor temperature is less than 5 °C.
Heating limit type¶
The input must be either LimitFlowRate, LimitCapacity, LimitFlowRateAndCapacity or NoLimit. LimitFlowRate means that the heating supply air flow rate will be limited to the value specified in the input field Max heat flow. LimitCapacity means that the sensible heating capacity will be limited to the value specified in the Max heating capacity field. LimitFlowRateAndCapacity means that both flow rate and capacity will be limited. NoLimit (the default) means that there will not be any limit on the heating supply air flow rate or capacity and the subsequent two fields will be ignored.
Max heating capacity¶
The maximum allowed sensible heating capacity in Watts if Heating Limit is set to LimitCapacity or LimitFlowRateAndCapacity. If blank, there is no limit. If Heating Limit is set to NoLimit or LimitFlowRate, this field is ignored.
Max heat flow¶
The maximum heating supply air flow rate in cubic meters per second if heating limit is set to LimitFlowRate or LimitFlowRateAndCapacity. This field is ignored if heating limit is set to NoLimit or LimitCapacity. If blank, there is no limit.
Heating CoP¶
Efficiency of heating system. This value is used in deriving total heating energy use by dividing the heating load by the heating efficiency.
Cooling¶
This checkbox field defines whether or not this component is available to operate. If this field is unchecked, the Cooling schedule field will be forced to the generic schedule name Off.
Cooling setpoint¶
The temperature above which zone heating is turned on. Umi controls the temperature in the zone using a ThermostatSetpoint:DualSetpoint object. This would be for heating and cooling thermostat where both a heating and cooling setpoint can be scheduled for any given time period.
Note
In this version of umi, the heating setpoint can only be scheduled as a constant.
Cooling schedule¶
The name of a schedule (ref: Schedule) that denotes whether cooling is available. A schedule value greater than 0 (usually 1 is used) indicates that cooling and dehumidification are available. A value less than or equal to 0 (usually 0 is used) denotes that cooling and dehumidification is not available. If blank, cooling and dehumidification are always available.
Note
Schedule for when the cooling system is available. Summer only enables the cooling system when the outdoor temperature is greater than 8 °C below the cooling setpoint.
Todo
to confirm
Cooling limit type¶
The input must be either LimitFlowRate, LimitCapacity, LimitFlowRateAndCapacity or NoLimit. LimitFlowrate means that the cooling supply air flow rate will be limited to the value specified Max cool flow field. LimitCapacity means that the total cooling capacity will be limited to the value specified in the Max cooling capacity field. LimitFlowRateAndCapacity means that both flow rate and capacity will be limited. NoLimit (the default) means that there will not be any limit on the cooling supply air flow rate or capacity and the subsequent two fields will be ignored.
Max cooling capacity¶
The maximum allowed total (sensible plus latent) cooling capacity in Watts per square meter if Cooling Limit is set to LimitCapacity or LimitFlowRateAndCapacity. If Cooling limit type is set to NoLimit or LimitFlowRate, this field is ignored.
Max cool flow¶
The maximum cooling supply air flow rate in cubic meters per second if Cooling Limit is set to LimitFlowRate or LimitFlowRateAndCapacity. This field is ignored if cooling limit is set to NoLimit or LimitCapacity. If blank, there is no limit. If Cooling Limit is set to NoLimit, this field is ignored. This field is required if Outdoor Air Control Type is TemperatureEconomizer in order to establish an upper limit on outdoor air flow when the economizer is active.
Cooling CoP¶
Performance factor of cooling system. This value is used in deriving the total cooling energy use by dividing the cooling load by the COP.
Mechanical ventilation¶
Mechanical Ventilation affects building energy consumption by forcing Fresh Air into the zones, air that needs to be treated. If on, an outdoor air quantity for use by the model will be calculated.
Mechanical ventilation schedule¶
This field is the reference to the schedule that defines how outdoor air requirements change over time. The schedule values are multiplied by the outdoor air flow rate defined by the next two fields. The schedule values must be between 0 and 1, inclusive. For example, if users specify the same schedule as the OccupancySchedule, this means that the current occupancy level will be used when computing the minimum outdoor air flow rate based on the next two fields.
Min fresh air per area¶
The design outdoor air volume flow rate per square meter of floor area (units are m3/s-m2). This input is used if Outdoor Air Method is Flow/Area, Sum or Maximum. The default value for this field is 0.
Note
Umi uses by default the Sum method which means that the flows calculated from the fields Min fresh air per person, Min fresh air per area, Outdoor Air Flow per Zone, and Air Changes per Hour (using the associated conversions to m3/s for each field) will be added to obtain the zone outdoor air flow rate.
Min fresh air per person¶
The design outdoor air volume flow rate per person for this zone in cubic meters per second per person. The default is 0.00944 (20 cfm per person). An outdoor air flow rate is calculated based on the total number of people for all People statements assigned to the zone. Occupancy schedule values are not applied during sizing calculations and are applied during the remainder of the simulation. This input is used if Outdoor Air Method is one of Outdoor Air Flow per Person, Sum, or Maximum.
Economizer type¶
This field specifies if there is an outdoor air economizer. The choices are: NoEconomizer, DifferentialDryBulb, or DifferentialEnthalpy. The default is NoEconomizer. DifferentialDryBulb and DifferentialEnthalpy mean that the economizer will increase the outdoor air flow rate above the minimum outdoor air flow (see fields Design Specification Outdoor Air Object Name and Demand Controlled Ventilation Type) when there is a cooling load and the outdoor air temperature or enthalpy is below the zone exhaust air temperature or enthalpy. The DifferentialDryBulb and DifferentialEnthalpy options require that the Max cool flow be specified which will be used as the limit for maximum outdoor air flow rate.
Heat recovery type¶
Select from None, Sensible, or Enthalpy. None means that there is no heat recovery. Sensible means that there is sensible heat recovery whenever the zone exhaust air temperature is more favorable than the outdoor air temperature. Enthalpy means that there is latent and sensible heat recovery whenever the zone exhaust air enthalpy is more favorable than the outdoor air enthalpy. The default is None.
Heat recovery efficiency (latent)¶
The latent heat recovery effectiveness, where effectiveness is defined as the change in supply humidity ratio divided by the difference in entering supply and relief air humidity ratios. The default is 0.65.
Heat recovery efficiency (sensible)¶
The sensible heat recovery effectiveness, where effectiveness is defined as the change in supply temperature divided by the difference in entering supply and relief air temperatures. The default is 0.70.