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I have a VAV system with a minimum flow fraction of 35%, however for some reason the minimum flow is limiting itself to around 49%.

I have verified that:

• The Outdoor air rate is less than the minimum 35% flow, and set as Fixed Minimum
• After quadruple checking all inputs, they all agree that 35% is the minimum requested flow rate, not 49%. The 35% is corroborated by reviewing the HTML output. It is only when looking at hourly reporting that I noticed that the flow never goes below 49%.

I have also verified that it is the percentage of total flow that is what is somehow being specified, not the actual flow. I verified this by modifying the maximum flow rate input and noticing that the minimum flow rate adjusted as well, maintaining the exact same percentage. This also leads me to believe it is not limiting itself to some demand that needs to be met.

This is a model right out of HVAC Template. What am I missing or forgetting as it seems, I have inadvertently indicated a minimum flow of ~49%

I have a VAV system with a minimum flow fraction of 35%, however for some reason the minimum flow is limiting itself to around 49%.

I have verified that:

• The Outdoor air rate is less than the minimum 35% flow, and set as Fixed Minimum
• After quadruple checking all inputs, they all agree that 35% is the minimum requested flow rate, not 49%. The 35% is corroborated by reviewing the HTML output. It is only when looking at hourly reporting that I noticed that the flow never goes below 49%.

I have also verified that it is the percentage of total flow that is what is somehow being specified, not the actual flow. I verified this by modifying the maximum flow rate input and noticing that the minimum flow rate adjusted as well, maintaining the exact same percentage. This also leads me to believe it is not limiting itself to some demand that needs to be met.

This is a model right out of HVAC Template. What am I missing or forgetting forgetting, as it seems, seems I have inadvertently indicated a minimum flow of ~49%~49%. Is there some known reason a VAV system would do this?

I have a VAV system with a minimum flow fraction of 35%, however for some reason the minimum flow is limiting itself to around 49%.

I have verified that:

• The Outdoor air rate is less than the minimum 35% flow, and set as Fixed Minimum
• After quadruple checking all inputs, they all agree that 35% is the minimum requested flow rate, not 49%. The 35% is corroborated by reviewing the HTML output. It is only when looking at hourly reporting that I noticed that the flow never goes below 49%.

I have also verified that it is the percentage of total flow that is what is somehow being specified, not the actual flow. I verified this by modifying the maximum flow rate input and noticing that the minimum flow rate adjusted as well, maintaining the exact same percentage. This also leads me to believe it is not limiting itself to some demand that needs to be met.

This is a model right out of HVAC Template. What am I missing or forgetting, as it seems I have inadvertently indicated a minimum flow of ~49%. Is there some known reason a VAV system would do this?

I have a VAV system with a minimum flow fraction of 35%, however for some reason the minimum flow is limiting itself to around 49%.

I have verified that:

• The Outdoor air rate is less than the minimum 35% flow, and set as Fixed Minimum
• After quadruple checking all inputs, they all agree that 35% is the minimum requested flow rate, not 49%. The 35% is corroborated by reviewing the HTML output. It is only when looking at hourly reporting that I noticed that the flow never goes below 49%.

I have also verified that it is the percentage of total flow that is what is somehow being specified, not the actual flow. I verified this by modifying the maximum flow rate input and noticing that the minimum flow rate adjusted as well, maintaining the exact same percentage. This also leads me to believe it is not limiting itself to some demand that needs to be met.

This is a model right out of HVAC Template. What am I missing or forgetting, as it seems I have inadvertently indicated a minimum flow of ~49%. Is there some known reason a VAV system would do this?

I have a VAV system with a minimum flow fraction of 35%, however for some reason the minimum flow is limiting itself to around 49%.

I have verified that:

• The Outdoor air rate is less than the minimum 35% flow, and set as Fixed Minimum
• After quadruple checking all inputs, they all agree that 35% is the minimum requested flow rate, not 49%. The 35% is corroborated by reviewing the HTML output. It is only when looking at hourly reporting that I noticed that the flow never goes below 49%.

I have also verified that it is the percentage of total flow that is what is somehow being specified, not the actual flow. I verified this by modifying the maximum flow rate input and noticing that the minimum flow rate adjusted as well, maintaining the exact same percentage. This also leads me to believe it is not limiting itself to some demand that needs to be met.

This is a model right out of HVAC Template. What am I missing or forgetting, as it seems I have inadvertently indicated a minimum flow of ~49%. Is there some known reason a VAV system would do this?

I have a VAV system with a minimum flow fraction of 35%, however for some reason the minimum flow is limiting itself to around 49%.

I have verified that:

• The Outdoor air rate is less than the minimum 35% flow, and set as Fixed Minimum
• After quadruple checking all inputs, they all agree that 35% is the minimum requested flow rate, not 49%. The 35% is corroborated by reviewing the HTML output. It is only when looking at hourly reporting that I noticed that the flow never goes below 49%.

I have also verified that it is the percentage of total flow that is what is somehow being specified, not the actual flow. I verified this by modifying the maximum flow rate input and noticing that the minimum flow rate adjusted as well, maintaining the exact same percentage. This also leads me to believe it is not limiting itself to some demand that needs to be met.

This is a model right out of HVAC Template. What am I missing or forgetting, as it seems I have inadvertently indicated a minimum flow of ~49%. Is there some known reason a VAV system would do this?

I have a VAV system with a minimum flow fraction of 35%, however for some reason the minimum flow is limiting itself to around 49%.

I have verified that:

• The Outdoor air rate is less than the minimum 35% flow, and set as Fixed Minimum
• After quadruple checking all inputs, they all agree that 35% is the minimum requested flow rate, not 49%. The 35% is corroborated by reviewing the HTML output. It is only when looking at hourly reporting that I noticed that the flow never goes below 49%.

I have also verified that it is the percentage of total flow that is what is somehow being specified, not the actual flow. I verified this by modifying the maximum flow rate input and noticing that the minimum flow rate adjusted as well, maintaining the exact same percentage. This also leads me to believe it is not limiting itself to some demand that needs to be met.

This is a model right out of HVAC Template. What am I missing or forgetting, as it seems I have inadvertently indicated a minimum flow of ~49%. Is there some known reason a VAV system would do this?

IDF file is attached.

The AirLoops in question are labelled AHU101 and AHU201.

it can be seen form the HTML outputs that the minimum flow of these systems are 35% of their max flow, e.g. 4.64 m3/s for AHU101.

Hourly output reports however confirm that AHU101 is only reducing its flow to ~6.6 m3/s.

I have a VAV system with a minimum flow fraction of 35%, however for some reason the minimum flow is limiting itself to around 49%.

I have verified that:

• The Outdoor air rate is less than the minimum 35% flow, and set as Fixed Minimum
• After quadruple checking all inputs, they all agree that 35% is the minimum requested flow rate, not 49%. The 35% is corroborated by reviewing the HTML output. It is only when looking at hourly reporting that I noticed that the flow never goes below 49%.

I have also verified that it is the percentage of total flow that is what is somehow being specified, not the actual flow. I verified this by modifying the maximum flow rate input and noticing that the minimum flow rate adjusted as well, maintaining the exact same percentage. This also leads me to believe it is not limiting itself to some demand that needs to be met.

This is a model right out of HVAC Template. What am I missing or forgetting, as it seems I have inadvertently indicated a minimum flow of ~49%. Is there some known reason a VAV system would do this?

IDF file is attached.

The AirLoops in question are labelled AHU101 and AHU201.

it can be seen form the HTML outputs that the minimum flow of these systems are 35% of their max flow, e.g. 4.64 m3/s for AHU101.

Hourly output reports however confirm that AHU101 is only reducing its flow to ~6.6 m3/s.

I have a VAV system with a minimum flow fraction of 35%, however for some reason the minimum flow is limiting itself to around 49%.

I have verified that:

• The Outdoor air rate is less than the minimum 35% flow, and set as Fixed Minimum
• After quadruple checking all inputs, they all agree that 35% is the minimum requested flow rate, not 49%. The 35% is corroborated by reviewing the HTML output. It is only when looking at hourly reporting that I noticed that the flow never goes below 49%.

I have also verified that it is the percentage of total flow that is what is somehow being specified, not the actual flow. I verified this by modifying the maximum flow rate input and noticing that the minimum flow rate adjusted as well, maintaining the exact same percentage. This also leads me to believe it is not limiting itself to some demand that needs to be met.

This is a model right out of HVAC Template. What am I missing or forgetting, as it seems I have inadvertently indicated a minimum flow of ~49%. Is there some known reason a VAV system would do this?

IDF file is attached.

The AirLoops in question are labelled AHU101 and AHU201.

it can be seen form from the HTML outputs that the minimum flow of these systems are 35% of their max flow, e.g. 4.64 m3/s for AHU101.

Hourly output reports however confirm that AHU101 is only reducing its flow to ~6.6 m3/s.