Auxiliary Plants play a crucial role in enabling engineers to design and tailor various auxiliary equipment such as elevators, escalators, and Service Hot Water (SWH) systems throughout a building.
We offer three SWH plant templates as options within the default auxiliary systems. In this article we list a comprehensive list of the inputs for the auxiliary plants.
The Service Hot Water modeling includes three options: Electric or Gas Storage systems, and Electric Instantaneous systems. Each of these systems can be further customized based on specific sizing criteria, equipment preferences, and pumping requirements. The input definitions for these customizations can be saved and easily reused through Personal and Firm Templates.
Service Hot Water Parameters for Electric Boiler SHW
Plant Sizing
Calculation Type: The way you want to model these systems across your project. Options are: Per Room, Per Plant
Max Temperature [°F (IP) | °C (SI)]: the maximum allowable temperature for the loop
Min Temperature [°F (IP) | °C (SI)]: the minimum allowable temperature for the loop
Max Flow Rate [GPM (IP) | L/S (SI)]: the maximum loop flow rate
Min Flow Rate [GPM (IP) | L/S (SI)]: the minimum loop flow rate
Heater Sizing
Design Mode: Options are Per Solar Collector Area, Per Unit, Per Floor Area, Per Person, Residential HUD-FHA Minimum or Peak Draw.
Time Storage[hr]: Capability of the tank to meet the peak energy demand.
Time for Tank Recovery[hr]: The duration required for the tank to return to its desired or optimal state after being depleted or used.
Nominal Tank Volume[ft^3] for Autoszing: Default tank volume.
Setpoints
Primary Heating Setpoint
Assigned Schedule: this is the assigned schedule which will control the setpoint value at all timesteps. Use this to apply temperature resets or other variability required.
Control Variable: options are Min Temperature, Max Temperature and Temperature.
Electric Service Hot Water
Name: A unique name for the equipment can be provided.
Fuel Type: specifies the type of fuel used by the boiler. Options are: Electricity, Gas, Propane, Fuel Oil #1, Diesel, District Heating
Tank Volume [ft^3]: The volume of the water heater tank. Defaults to Autosized
Heater Capacity[Btu/h]: The heating capacity of the water tank. Defaults to Autosized
Heater Thermal Efficiency: The heater's efficiency.
Max Leaving Heating Hot Water Temp Limit [°F] : Maximum leaving temperature
Use Side Design Fluid Flow [gpm]: Input for the use side design fluid flow. Defaults to Autosized.
Source Side Design Fluid Flow[gpm]: Input for the source side design fluid flow. Defaults to Autosized.
Heater Control Type: The options are Cycle or Modulate
Cold Water Supply Temp Schedule: This is the assigned schedule which will control the cold water supply temperature at all timesteps. Use this to apply temperature resets or other variability required.
Pumping Strategies
Primary Pump Type: Constant or Variable
Variable Speed Pump
Name: A unique name for the equipment can be provided.
Location: The pumping location is set to primary.
Rated Flow Rate: [GPM (IP) | L/S (SI)]: the pump’s design volume flow rate. Defaults to Autosized.
Rated Pump Pressure ft Water [Watts (IP/SI)]: [psi (IP) | Pa (SI)]: the pump’s design head pressure. Defaults to Autosized.
Rated Power [hp]: Defaults to Autosized.
Motor efficiency: The pump motor’s efficiency in decimal form.
Min Flow Rate: [GPM (IP) | L/S (SI)]: the minimum volume flow rate while operating in variable flow capacity rate. Defaults to Autosized.
Control Type : Choices are
Continuous - the pump will run regardless of whether or not there is a load. This may have the net effect of adding heat to the loop if no equipment is turned on.
Intermittent - the pump will run at its capacity if a load is sensed and will shut off if there is no load on the loop.
Min Flow Fraction: the minimum fluid volumetric flow rate for pumps, specified as a fraction of the maximum fluid flow rate.
Constant Speed Pump
Name: A unique name for the equipment can be provided.
Location: The pumping location is set to primary.
Rated Flow Rate: [GPM (IP) | L/S (SI)]: the pump’s design volume flow rate. Defaults to Autosized.
Rated Pump Pressure ft Water [Watts (IP/SI)]: [psi (IP) | Pa (SI)]: the pump’s design head pressure. Defaults to Autosized.
Rated Power [hp]: Defaults to Autosized.
Motor efficiency: The pump motor’s efficiency in decimal form.
Control Type : Choices are
Continuous - the pump will run regardless of whether or not there is a load. This may have the net effect of adding heat to the loop if no equipment is turned on.
Intermittent - the pump will run at its capacity if a load is sensed and will shut off if there is no load on the loop.
Service Hot Water Parameters for Gas Boiler SHW
Plant Sizing
Calculation Type: The way you want to model these systems across your project. Options are: Per Room, Per Plant
Max Temperature [°F (IP) | °C (SI)]: the maximum allowable temperature for the loop
Min Temperature [°F (IP) | °C (SI)]: the minimum allowable temperature for the loop
Max Flow Rate [GPM (IP) | L/S (SI)]: the maximum loop flow rate
Min Flow Rate [GPM (IP) | L/S (SI)]: the minimum loop flow rate
Heater Sizing
Design Mode: Options are Per Solar Collector Area, Per Unit, Per Floor Area, Per Person, Residential HUD-FHA Minimum or Peak Draw.
Time Storage[hr]: Capability of the tank to meet the peak energy demand.
Time for Tank Recovery[hr]: The duration required for the tank to return to its desired or optimal state after being depleted or used.
Nominal Tank Volume[ft^3] for Autoszing: Default tank volume.
Setpoints
Primary Heating Setpoint
Assigned Schedule: this is the assigned schedule which will control the setpoint value at all timesteps. Use this to apply temperature resets or other variability required.
Control Variable: options are Min Temperature, Max Temperature and Temperature.
Gas Boiler Service Hot Water
Name: A unique name for the equipment can be provided.
Fuel Type: specifies the type of fuel used by the boiler. Options are: Electricity, Gas, Propane, Fuel Oil #1, Diesel, District Heating
Tank Volume [ft^3]: The volume of the water heater tank. Defaults to Autosized
Heater Capacity[Btu/h]: The heating capacity of the water tank. Defaults to Autosized
Heater Thermal Efficiency: The heater's efficiency.
Max Leaving Heating Hot Water Temp Limit [°F] : Maximum leaving temperature.
Use Side Design Fluid Flow [gpm]: Input for the use side design fluid flow. Defaults to Autosized
Source Side Design Fluid Flow[gpm]: Input for the source side design fluid flow. Defaults to Autosized.
Heater Control Type: The options are Cycle or Modulate
Cold Water Supply Temp Schedule: This is the assigned schedule which will control the cold water supply temperature at all timesteps. Use this to apply temperature resets or other variability required.
Pumping Strategies
Primary Pump Type: Constant or Variable
Variable Speed Pump
Name: A unique name for the equipment can be provided.
Location: The pumping location is set to primary.
Rated Flow Rate: [GPM (IP) | L/S (SI)]: the pump’s design volume flow rate. Defaults to Autosized.
Rated Pump Pressure ft Water [Watts (IP/SI)]: [psi (IP) | Pa (SI)]: the pump’s design head pressure. Defaults to Autosized.
Rated Power [hp]: Defaults to Autosized.
Motor efficiency: The pump motor’s efficiency in decimal form.
Min Flow Rate: [GPM (IP) | L/S (SI)]: the minimum volume flow rate while operating in variable flow capacity rate. Defaults to Autosized.
Control Type : Choices are
Continuous - the pump will run regardless of whether or not there is a load. This may have the net effect of adding heat to the loop if no equipment is turned on.
Intermittent - the pump will run at its capacity if a load is sensed and will shut off if there is no load on the loop.
Min Flow Fraction: the minimum fluid volumetric flow rate for pumps, specified as a fraction of the maximum fluid flow rate
Constant Speed Pump
Name: A unique name for the equipment can be provided.
Location: The pumping location is set to primary.
Rated Flow Rate: [GPM (IP) | L/S (SI)]: the pump’s design volume flow rate. Defaults to Autosized.
Rated Pump Pressure ft Water [Watts (IP/SI)]: [psi (IP) | Pa (SI)]: the pump’s design head pressure. Defaults to Autosized.
Rated Power [hp]: Defaults to Autosized.
Motor efficiency: The pump motor’s efficiency in decimal form.
Control Type : Choices are
Continuous - the pump will run regardless of whether or not there is a load. This may have the net effect of adding heat to the loop if no equipment is turned on.
Intermittent - the pump will run at its capacity if a load is sensed and will shut off if there is no load on the loop.
Service Hot Water Parameters for Electric Instantaneous SHW
Plant Sizing
Calculation Type: The way you want to model these systems across your project. Options are: Per Room, Per Plant
Max Temperature [°F (IP) | °C (SI)]: the maximum allowable temperature for the loop
Min Temperature [°F (IP) | °C (SI)]: the minimum allowable temperature for the loop
Max Flow Rate [GPM (IP) | L/S (SI)]: the maximum loop flow rate
Min Flow Rate [GPM (IP) | L/S (SI)]: the minimum loop flow rate
Heater Sizing
Design Mode: Options are Per Solar Collector Area, Per Unit, Per Floor Area, Per Person, Residential HUD-FHA Minimum or Peak Draw.
Time Storage[hr]: Capability of the tank to meet the peak energy demand.
Time for Tank Recovery[hr]: The duration required for the tank to return to its desired or optimal state after being depleted or used.
Nominal Tank Volume[ft^3] for Autoszing: Default tank volume.
Setpoints
Primary Heating Setpoint
Assigned Schedule: this is the assigned schedule which will control the setpoint value at all timesteps. Use this to apply temperature resets or other variability required.
Control Variable: options are Min Temperature, Max Temperature and Temperature.
Gas Boiler Service Hot Water
Name: A unique name for the equipment can be provided.
Fuel Type: specifies the type of fuel used by the boiler. Options are: Electricity, Gas, Propane, Fuel Oil #1, Diesel, District Heating
Tank Volume [ft^3]: The volume of the water heater tank. Defaults to Autosized
Heater Capacity[Btu/h]: The heating capacity of the water tank. Defaults to Autosized
Heater Thermal Efficiency: The heater's efficiency.
Max Leaving Heating Hot Water Temp Limit [°F] : Maximum leaving temperature
Use Side Design Fluid Flow [gpm]: Input for the use side design fluid flow. Defaults to Autosized
Source Side Design Fluid Flow[gpm]: Input for the source side design fluid flow. Defaults to Autosized.
Heater Control Type: The options are Cycle or Modulate
Cold Water Supply Temp Schedule: This is the assigned schedule which will control the cold water supply temperature at all timesteps. Use this to apply temperature resets or other variability required.
Pumping Strategies
Primary Pump Type: Constant or Variable
Variable Speed Pump
Name: A unique name for the equipment can be provided.
Location: The pumping location is set to primary.
Rated Flow Rate: [GPM (IP) | L/S (SI)]: the pump’s design volume flow rate. Defaults to Autosized.
Rated Pump Pressure ft Water [Watts (IP/SI)]: [psi (IP) | Pa (SI)]: the pump’s design head pressure. Defaults to Autosized.
Rated Power [hp]: Defaults to Autosized.
Motor efficiency: The pump motor’s efficiency in decimal form.
Min Flow Rate: [GPM (IP) | L/S (SI)]: the minimum volume flow rate while operating in variable flow capacity rate. Defaults to Autosized.
Control Type : Choices are
Continuous - the pump will run regardless of whether or not there is a load. This may have the net effect of adding heat to the loop if no equipment is turned on.
Intermittent - the pump will run at its capacity if a load is sensed and will shut off if there is no load on the loop.
Min Flow Fraction: the minimum fluid volumetric flow rate for pumps, specified as a fraction of the maximum fluid flow rate
Constant Speed Pump
Name: A unique name for the equipment can be provided.
Location: The pumping location is set to primary.
Rated Flow Rate: [GPM (IP) | L/S (SI)]: the pump’s design volume flow rate. Defaults to Autosized.
Rated Pump Pressure ft Water [Watts (IP/SI)]: [psi (IP) | Pa (SI)]: the pump’s design head pressure. Defaults to Autosized.
Rated Power [hp]: Defaults to Autosized.
Motor efficiency: The pump motor’s efficiency in decimal form.
Control Type : Choices are
Continuous - the pump will run regardless of whether or not there is a load. This may have the net effect of adding heat to the loop if no equipment is turned on.
Intermittent - the pump will run at its capacity if a load is sensed and will shut off if there is no load on the loop.