Flow Configuration

[ajay_johnganesan]

Hi guys,

I just came up to this Flow Configuration 1. Calculated, 2. Preset 3. System 4. Fixture Units. What are these? What's the use of this? What is the difference between one another. Could someone explain in detail

[RLY_15]

https://forums.autodesk.com/t5/revit-mep-forum/hello-i-am-new-to-revit-and-wanted-to-ask-about-conne...

[ajay_johnganesan]

Thanks for your valuable reply

I still have some doubts that I would like to ask. Lets say a Water tank (plumbing equipment) is set to Calculated & flow direction is Out connected to a fixture which is also set to Calculated. when both of this is set to calculated what would happen? Will calculation happens? i tried with a tank and connected to a washbasin where both are set to calculated but no calculation happens

[RLY_15]

If there is a mismatch, Revit will not correctly calculate the flow, if it even attempts to do anything at all. The link that was provided in that other thread is a primer on how to set up connector types based on different context (VAV boxes, pumps, etc.). If you deviate from the connector rules, it simply doesn't work correctly.

Terminal units (Plumbing Fixtures, Air Terminals, Fan Coils without discharge ductwork, etc.) need to have their connectors set to Fixture Units or Preset depending on context. Those are aggregated by your pipe or duct network back to the equipment up the line, which would have its connector set to Calculated so as to pull in these values.

Where it can get weird is Water Heaters and how the cold service input side interacts with the hot service output.

[pkomatlapalli]

Hi @ajay_johnganesan ,

Did the info from RLY_15  help answer your question?

If it did, it’d be great if you could click the "Accept Solution" button so others can easily find it too.

If you’re still needing more help, feel free to share an update here. The community will be happy to jump in with any next steps to help you get where you need to be.
 

[ajay_johnganesan]

nope I didn't get any solution as of now

[RLY_15]

What solution are you looking for? The link provided (in the thread I linked) serves as documentation for 90% of expected use. Is there are particular system design you need clarification for?

[pkomatlapalli]

Hello, @ajay_johnganesan ,

We are sorry to hear that you are still experiencing issues. We would like to suggest contacting Support for further assistance. They can help determine a possible workaround or if this is a bug, it can be reported to the appropriate team for triaging. You can always use the Autodesk Assistant on the support page to find answers or contact support.

Thank you for being a part of the community!
 

[RLY_15]

Pavan,

There is no workaround or bug to be reported. They were looking for an explanation on how Flow Configuration worked for Connectors. A link was provided that paths to the (very regularly referenced) Revit whitepaper on how to set up the Flow Configuration on various systems. All that's left to do is to review the documentation and ask additional clarifying questions...

[iainsavage]

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@ajay_johnganesan wrote:

Thanks for your valuable reply

I still have some doubts that I would like to ask. Lets say a Water tank (plumbing equipment) is set to Calculated & flow direction is Out connected to a fixture which is also set to Calculated. when both of this is set to calculated what would happen? Will calculation happens? i tried with a tank and connected to a washbasin where both are set to calculated but no calculation happens

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Set the connect at the tank to Calculated.

Set the connections at plumbing fixtures to Preset or Fixture Unit and apply values for each fixture.

The flow values from each plumbing fixture will be passed through the pipe system, added together at each branch and the total flow will be applied (Calculated) at the water tank.

Preset means that you apply a fixed value for flow.

Fixture Unit applies diversity factors in accordance with US based "International Plumbing Code"

Calculated means that Revit calculates the value as I describe above.

System is similar to Calculated but is usually used when you have multiple equipment elements such two tanks in parallel (then you a apply a system factor to each to tell Revit what proportion of the Calculated flow will be apportioned to each piece of equipment).

It is all explained in that link that @RLY_15 shared.

[iainsavage]

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@pkomatlapalli wrote:

Hello, @ajay_johnganesan,

We are sorry to hear that you are still experiencing issues. We would like to suggest contacting Support for further assistance. They can help determine a possible workaround or if this is a bug, it can be reported to the appropriate team for triaging. You can always use the Autodesk Assistant on the support page to find answers or contact support.

Thank you for being a part of the community!
 

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I'm surprised that you, as an Autodesk representative, are suggesting that this might be a bug.

It is a basic misunderstanding by an inexperienced user and is fully covered in Help, associated materials such as the AU2008 document "Getting Into the Flow: Understanding Connectors in Revit MEP Content" and many similar posts on this forum.