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I'm trying to understand the vast differences I get in energy usage between different SetpointManager options. From what I can tell from the I/O and Engineering References:

SetpointManager:Warmestresets the cooling SAT based on the cooling demand of the warmest zone, at the maximum zone supply air flow rate.

SetpointManager:WarmestTemperatureFlow "Temp First" resets the cooling SAT based on the cooling demand of the warmest zone, at the zone minimum supply air flow rate. If this SAT is less than the minimum, the SAT is set to the minimum, and the flow rate is increased until the cooling loads are met.

SetpointManager:WarmestTemperatureFlow "Flow First" resets the supply air flow rate based on the cooling demand of the warmest zone, at the zone maximum supply air temperature. If the flow is greater than the maximum, the flow is set to the maximum and the SAT is reduced until the cooling loads are met.

Questions:

1. Why do these options yield such different results? I tested all three and came up with this plot of HVAC energy usage:

1. In what scenarios would it make sense to implement the SetpointManager:WarmestTemperatureFlow Flow First or Temperature First options?

I'm trying to understand the vast differences I get in energy usage between different SetpointManager options. From what I can tell from the I/O and Engineering References:

SetpointManager:Warmestresets the cooling SAT based on the cooling demand of the warmest zone, at the maximum zone supply air flow rate.

SetpointManager:WarmestTemperatureFlow "Temp First" resets the cooling SAT based on the cooling demand of the warmest zone, at the zone minimum supply air flow rate. If this SAT is less than the minimum, the SAT is set to the minimum, and the flow rate is increased until the cooling loads are met.

SetpointManager:WarmestTemperatureFlow "Flow First" resets the supply air flow rate based on the cooling demand of the warmest zone, at the zone maximum supply air temperature. If the flow is greater than the maximum, the flow is set to the maximum and the SAT is reduced until the cooling loads are met.

Questions:

1. Why do these options yield such different results? I tested all three in a project with a VAV reheat system and came up with this plot of HVAC energy usage:usage. I also plotted hourly results from the same node as the setpoint manager, but wasn't able to make sense of the results.

1. In what scenarios would it make sense to implement the SetpointManager:WarmestTemperatureFlow Flow First or Temperature First options?

I'm trying to understand the vast differences I get in energy usage between different SetpointManager options. From what I can tell from the I/O and Engineering References:

SetpointManager:Warmestresets the cooling SAT based on the cooling demand of the warmest zone, at the maximum zone supply air flow rate.

SetpointManager:WarmestTemperatureFlow "Temp First" resets the cooling SAT based on the cooling demand of the warmest zone, at the zone minimum supply air flow rate. If this SAT is less than the minimum, the SAT is set to the minimum, and the flow rate is increased until the cooling loads are met.

SetpointManager:WarmestTemperatureFlow "Flow First" resets the supply air flow rate based on the cooling demand of the warmest zone, at the zone maximum supply air temperature. If the flow is greater than the maximum, the flow is set to the maximum and the SAT is reduced until the cooling loads are met.

Questions:

1. Why do these options yield such different results? I tested all three in a project (from CBECC-Com) with a built-up VAV reheat system (water-cooled chiller, and boiler) and came up with this plot of HVAC energy usage. I also plotted hourly results from the same node as the setpoint manager, but wasn't able to make sense of the results.

1. In what scenarios would it make sense to implement the SetpointManager:WarmestTemperatureFlow Flow First or Temperature First options?

I'm trying to understand the vast differences I get in energy usage between different SetpointManager options. This originated from a CBECC-Com model, but I don't think that is too relevant. From what I can tell from the I/O and Engineering References:

SetpointManager:Warmestresets the cooling SAT based on the cooling demand of the warmest zone, at the maximum zone supply air flow rate.

SetpointManager:WarmestTemperatureFlow "Temp First" resets the cooling SAT based on the cooling demand of the warmest zone, at the zone minimum supply air flow rate. If this SAT is less than the minimum, the SAT is set to the minimum, and the flow rate is increased until the cooling loads are met.

SetpointManager:WarmestTemperatureFlow "Flow First" resets the supply air flow rate based on the cooling demand of the warmest zone, at the zone maximum supply air temperature. If the flow is greater than the maximum, the flow is set to the maximum and the SAT is reduced until the cooling loads are met.

Questions:

1. Why do these options yield such different results? I tested all three in a project (from CBECC-Com) with a built-up VAV reheat system (water-cooled chiller, and boiler) and came up with this plot of HVAC energy usage. I also plotted hourly results from the same node as the setpoint manager, but wasn't able to make sense of the results.

1. In what scenarios would it make sense to implement the SetpointManager:WarmestTemperatureFlow Flow First or Temperature First options?

I'm trying to understand the vast differences I get in energy usage between different SetpointManager options. This originated from a CBECC-Com model, but I don't think that is too relevant. From what I can tell from the I/O and Engineering References:

SetpointManager:Warmestresets the cooling SAT based on the cooling demand of the warmest zone, at the maximum zone supply air flow rate.

SetpointManager:WarmestTemperatureFlow "Temp First" resets the cooling SAT based on the cooling demand of the warmest zone, at the zone minimum supply air flow rate. If this SAT is less than the minimum, the SAT is set to the minimum, and the flow rate is increased until the cooling loads are met.

SetpointManager:WarmestTemperatureFlow "Flow First" resets the supply air flow rate based on the cooling demand of the warmest zone, at the zone maximum supply air temperature. If the flow is greater than the maximum, the flow is set to the maximum and the SAT is reduced until the cooling loads are met.

Questions:

1. Why do these options yield such different results? I tested all three in a project (from CBECC-Com) with a built-up VAV reheat system (water-cooled chiller, and boiler) and came up with this plot of HVAC energy usage. I also plotted hourly results from the same node as the setpoint manager, but wasn't able to make sense of the results.

1. In what scenarios would it make sense to implement the SetpointManager:WarmestTemperatureFlow Flow First or Temperature First options?

I'm trying to understand the vast differences I get in energy usage between different SetpointManager options. This originated from a CBECC-Com model, but I don't think that is too relevant. From what I can tell from the I/O and Engineering References:

SetpointManager:Warmestresets the cooling SAT based on the cooling demand of the warmest zone, at the maximum zone supply air flow rate.

SetpointManager:WarmestTemperatureFlow "Temp First" resets the cooling SAT based on the cooling demand of the warmest zone, at the zone minimum supply air flow rate. If this SAT is less than the minimum, the SAT is set to the minimum, and the flow rate is increased until the cooling loads are met.

SetpointManager:WarmestTemperatureFlow "Flow First" resets the supply air flow rate based on the cooling demand of the warmest zone, at the zone maximum supply air temperature. If the flow is greater than the maximum, the flow is set to the maximum and the SAT is reduced until the cooling loads are met.

Questions:

1. Why do these options yield such different results? I tested all three in a project (from CBECC-Com) with a built-up VAV reheat system (water-cooled chiller, and boiler) and came up with this plot of HVAC energy usage. Everything in the models is hard-sized. I also plotted hourly results from the same node as the setpoint manager, but wasn't able to make sense of the results.

1. In what scenarios would it make sense to implement the SetpointManager:WarmestTemperatureFlow Flow First or Temperature First options?

I'm trying to understand the vast differences I get in energy usage between different SetpointManager options. This originated from a CBECC-Com model, but I don't think that is too relevant. From what I can tell from the I/O and Engineering References:

SetpointManager:Warmestresets the cooling SAT based on the cooling demand of the warmest zone, at the maximum zone supply air flow rate.

SetpointManager:WarmestTemperatureFlow "Temp First" resets the cooling SAT based on the cooling demand of the warmest zone, at the zone minimum supply air flow rate. If this SAT is less than the minimum, the SAT is set to the minimum, and the flow rate is increased until the cooling loads are met.

SetpointManager:WarmestTemperatureFlow "Flow First" resets the supply air flow rate based on the cooling demand of the warmest zone, at the zone maximum supply air temperature. If the flow is greater than the maximum, the flow is set to the maximum and the SAT is reduced until the cooling loads are met.

Questions:

1. Why do these options yield such different results? I tested all three in a project (from CBECC-Com) with a built-up VAV reheat system (water-cooled chiller, and boiler) and came up with this plot of HVAC energy usage. Everything in the models is hard-sized. I also plotted hourly results from the same node as the setpoint manager, but wasn't able to make sense of the results.

1. In what scenarios would it make sense to implement the SetpointManager:WarmestTemperatureFlow Flow First or Temperature First options?

I'm trying to understand the vast differences I get in energy usage between different SetpointManager options. This originated from a CBECC-Com model, but I don't think that is too relevant. From what I can tell from the I/O and Engineering References:

SetpointManager:Warmestresets the cooling SAT based on the cooling demand of the warmest zone, at the maximum zone supply air flow rate.

SetpointManager:WarmestTemperatureFlow "Temp First" resets the cooling SAT based on the cooling demand of the warmest zone, at the zone minimum supply air flow rate. If this SAT is less than the minimum, the SAT is set to the minimum, and the flow rate is increased until the cooling loads are met.

SetpointManager:WarmestTemperatureFlow "Flow First" resets the supply air flow rate based on the cooling demand of the warmest zone, at the zone maximum supply air temperature. If the flow is greater than the maximum, the flow is set to the maximum and the SAT is reduced until the cooling loads are met.

Questions:

1. Why do these options yield such different results? I tested all three in a project (from CBECC-Com) with a built-up VAV reheat system (water-cooled chiller, and boiler) and came up with this plot of HVAC energy usage. Everything in the models is hard-sized. I also plotted hourly results from the same node as the setpoint manager, but wasn't able to make sense of the results.

   

   Questions:

   1. Why do these options yield such different results?

   

   1. In what scenarios would it make sense to implement the SetpointManager:WarmestTemperatureFlow Flow First or Temperature First options?options vs the SetpointManager:Warmest? I want to generally understand what the pros and cons are for each option for different system configurations.

I'm trying to understand the vast differences I get in energy usage between different SetpointManager options. This originated from a CBECC-Com model, but I don't think that is too relevant. model. From what I can tell from the I/O and Engineering References:

SetpointManager:Warmestresets the cooling SAT based on the cooling demand of the warmest zone, at the maximum zone supply air flow rate.

SetpointManager:WarmestTemperatureFlow "Temp First" resets the cooling SAT based on the cooling demand of the warmest zone, at the zone minimum supply air flow rate. If this SAT is less than the minimum, the SAT is set to the minimum, and the flow rate is increased until the cooling loads are met.

SetpointManager:WarmestTemperatureFlow "Flow First" resets the supply air flow rate based on the cooling demand of the warmest zone, at the zone maximum supply air temperature. If the flow is greater than the maximum, the flow is set to the maximum and the SAT is reduced until the cooling loads are met.

I tested all three in a project (from CBECC-Com) with a built-up VAV reheat system (water-cooled chiller, and boiler) and came up with this plot of HVAC energy usage. Everything in the models is hard-sized. I also plotted hourly results from the same node as the setpoint manager, but wasn't able to make sense of the results.

Questions:

1. Why do these options yield such different results?

2. In what scenarios would it make sense to implement the SetpointManager:WarmestTemperatureFlow Flow First or Temperature First options vs the SetpointManager:Warmest? I want to generally understand what the pros and cons are for each option for different system configurations.

I'm trying to understand the vast differences I get in energy usage between different SetpointManager options. This originated from a CBECC-Com model. From what I can tell from the I/O and Engineering References:

SetpointManager:Warmestresets the cooling SAT based on the cooling demand of the warmest zone, at the maximum zone supply air flow rate.

SetpointManager:WarmestTemperatureFlow "Temp First" resets the cooling SAT based on the cooling demand of the warmest zone, at the zone minimum supply air flow rate. If this SAT is less than the minimum, the SAT is set to the minimum, and the flow rate is increased until the cooling loads are met.

SetpointManager:WarmestTemperatureFlow "Flow First" resets the supply air flow rate based on the cooling demand of the warmest zone, at the zone maximum supply air temperature. If the flow is greater than the maximum, the flow is set to the maximum and the SAT is reduced until the cooling loads are met.

I tested all three in a project (from CBECC-Com) with a built-up VAV reheat system (water-cooled chiller, and boiler) and came up with this plot of HVAC energy usage. Everything in the models is hard-sized. I also plotted hourly results from the same node as the setpoint manager, but wasn't able to make sense of the results.

Questions:

1. Why do these options yield such different results?

2. In what scenarios would it make sense to implement the SetpointManager:WarmestTemperatureFlow Flow First or Temperature First options vs the SetpointManager:Warmest? I want to generally understand what the pros and cons are for each option for different system configurations.