> ## Documentation Index
> Fetch the complete documentation index at: https://documentation.kodelabs.com/llms.txt
> Use this file to discover all available pages before exploring further.

# AHU workflows

> Reference for all AHU functional testing workflows including cooling operation, heating operation, mixed damper operation, and VFD operation tests.

Cloud BMS provides a library of pre-configured AHU (Air Handling Unit) functional testing workflows. Each workflow commands cooling, heating, dampers, or VFDs, reads sensor response, and scores pass or fail against thresholds.

Use this page as a parameter and point-requirements lookup. For how scores are produced, see [How to read a score](/products/ftt/test-results#how-to-read-a-score). For deployment order, see the [Deployment guide](/products/ftt/deployment).

Select a tab to open the workflow you need.

***

<Tabs>
  <Tab title="Cooling operation" icon="snowflake">
    *This workflow tests an AHU (air handling unit) for its cooling operation. It verifies the AHU is running, eliminates outside sources of heating and cooling, and then commands cooling to confirm the unit can deliver cooled air.*

    <Check>
      **Outcome:** This test verifies an AHU's ability to deliver cooled air when the cooling system is commanded on.
    </Check>

    <Tip>
      **Recommended schedule:** Run seasonally (when cooling is first needed) per AHU. Run when there are comfort complaints in a space or floor. Run when AHUs are installed and/or reprogrammed.
    </Tip>

    <Info>
      **Point requirements:**

      | Device | Required points                                                                                                   |
      | ------ | ----------------------------------------------------------------------------------------------------------------- |
      | AHU    | Discharge Air Pressure, Discharge Air Temperature, Mixed Air Temperature, Return Air Temperature, Cooling Command |
    </Info>

    ### Required pre-conditions

    1. *AHU Occupancy Mode* is `Occupied`
    2. *AHU Duct Pressure* exceeds `0.4psi` \[Pressure Min Threshold]
    3. *AHU Return Air Temperature* is below `60°F` \[RAT Cooling Threshold]

    <Warning>
      If any of these conditions are not met, the workflow stops and the test is archived.
    </Warning>

    ### Workflow overview

    **1 Pre-Condition Check**

    * Verify device is `Occupied`
    * *Duct Pressure* exceeds `Pressure Min Threshold`
    * *Return Air Temperature* below `RAT Cooling Threshold`

    **2 Stop Active Heating**

    * **Success:** *Discharge Air Temperature* is within `10△°F` \[Heating - Delta] above *Mixed Air Temperature*

    **3 Stop Active Cooling**

    * **Success:** *Discharge Air Temperature* is within `10△°F` \[Cooling - Delta] below *Mixed Air Temperature*

    **4 Open Mixed Damper**

    * **Success:** *Mixed Air Temperature* is within `5△°F` \[Ventilation - Delta] below *Return Air Temperature*

    **5 Start Cooling**

    * **Control:** Command *Cooling* to `ON`
    * **Success:** *Discharge Air Temperature* is `10△°F` \[Cooling - Delta] more than *Mixed Air Temperature*, or if *Mixed Air Temperature* is not available, *Discharge Air Temperature* exceeds `45°F` \[DAT Arb Cooling Threshold]

    ### Tuning parameters

    | #  | Parameter                                  | Description                                                                     |
    | -- | ------------------------------------------ | ------------------------------------------------------------------------------- |
    | 1  | `Pressure Min Threshold` \[0.4psi]         | Minimum duct pressure required for the test to begin                            |
    | 2  | `RAT Cooling Threshold` \[60°F]            | Maximum return air temperature for the loop to provide cooling                  |
    | 3  | `Loop Diff Pressure Min Threshold` \[3△°F] | Minimum loop system differential pressure                                       |
    | 4  | `Ventilation Delta` \[5△°F]                | Temperature threshold tolerance for fully open mixed damper (delta below RAT)   |
    | 5  | `Cooling Delta` \[10△°F]                   | Threshold tolerance for cooling (delta between MAT and DAT)                     |
    | 6  | `Heating Delta` \[10△°F]                   | Threshold tolerance for heating (delta between MAT and DAT)                     |
    | 7  | `DAT Arb Cooling Threshold` \[45°F]        | DAT below which there is indication of cooling                                  |
    | 8  | `Reaction Time` \[300sec]                  | Time to wait for actuators to complete their action                             |
    | 9  | `Stabilization Time` \[60sec]              | Time to wait for the system to stabilize after a command and conditions are met |
    | 10 | `Measure After` \[60sec]                   | Time in seconds to wait before checking feedback readings                       |

    <Note>
      If you need assistance with interpreting your results, reach out to the support team at [support@kodelabs.com](mailto:support@kodelabs.com).
    </Note>

    ***
  </Tab>

  <Tab title="Heating operation" icon="flame">
    *This workflow will test an AHU (air handling unit) for its heating operation.*

    1. First, we display the initial conditions of the equipment.
    2. Then, KODE performs pre-condition checks to ensure the equipment is ready to be tested.
    3. Once confirmed, KODE will stop cooling by commanding the chilled water valve to close fully.
    4. Then, KODE will stop heating by commanding the steam valve to close fully.
    5. Finally, we will command the steam valve to fully open to restart heating.

    <Check>
      **Outcome:** This test will check an AHU's ability to deliver heat when its steam valve is fully opened.
    </Check>

    <Tip>
      **Recommended schedule:** Run seasonally (when heating is first needed) per AHU. Run when there are comfort complaints in a space or floor. Run when AHUs are installed and/or reprogrammed.
    </Tip>

    <Info>
      **Point requirements:**

      | Device     | Required points                                                                                                                                  |
      | ---------- | ------------------------------------------------------------------------------------------------------------------------------------------------ |
      | AHU        | Discharge Air Pressure, Discharge Air Temperature, Mixed Air Temperature, Chilled Water Valve Percentage Command, Steam Valve Percentage Command |
      | HHW System | Primary Loop Heating Hot Water Valve Percentage Sensor                                                                                           |
    </Info>

    ### Required pre-conditions

    1. *AHU Discharge Air Pressure* exceeds `AHU Minimum Discharge Air Pressure Threshold`
    2. *HHW System Valve* exceeds `Minimum HHW System Valve Threshold`

    **Variations:** There is a variant of this workflow that works with AHU hot water valves instead of steam valves.

    ### Workflow overview

    **1 Pre-Condition Check**

    * *AHU Discharge Air Pressure* exceeds `Discharge Air Pressure Minimum`
    * *HHW System Valve* exceeds `HHW Loop Valve Minimum`

    **2 Stop Cooling**

    * **Control:** Command *AHU chilled water valve* to `CHW Valve Close Command`
    * **Success:** *AHU Discharge Air Temperature* ≥ *AHU Mixed Air Temperature* - `Stop Cooling DAT-MAT Differential`

    **3 Stop Heating**

    * **Control:** Command *AHU steam valve* to `Hot Water Valve Close Command`
    * **Success:** *AHU Discharge Air Temperature* ≤ *AHU Mixed Air Temperature* + `Stop Heating DAT-MAT Differential`

    **4 Start Heating**

    * **Control:** Command *AHU steam valve* to `Hot Water Valve Open Command`
    * **Success:** *AHU Discharge Air Temperature* ≥ *AHU Mixed Air Temperature* + `Start Heating DAT-MAT Differential`

    ### Tuning parameters

    | #  | Parameter                            | Description                                                                 |
    | -- | ------------------------------------ | --------------------------------------------------------------------------- |
    | 1  | `Discharge Air Pressure Minimum`     | Minimum AHU discharge air pressure required for the test to begin running   |
    | 2  | `HHW Loop Valve Minimum`             | Minimum primary HHW loop valve position for HWS to be considered enabled    |
    | 3  | `CHW Valve Close Command`            | Percentage command to close the chilled water valve when stopping cooling   |
    | 4  | `Stop Cooling DAT-MAT Differential`  | Differential between DAT and MAT for Stop Cooling test to run successfully  |
    | 5  | `Hot Water Valve Close Command`      | Percentage command to close the hot water valve when stopping heating       |
    | 6  | `Stop Heating DAT-MAT Differential`  | Differential between DAT and MAT for Stop Heating test to run successfully  |
    | 7  | `Hot Water Valve Open Command`       | Percentage command to open the hot water valve when starting heating        |
    | 8  | `Start Heating DAT-MAT Differential` | Differential between DAT and MAT for Start Heating test to run successfully |
    | 9  | `Min Sequence Duration`              | Minimum length of time in seconds that a sequence should take to execute    |
    | 10 | `Max Sequence Duration`              | Maximum length of time in seconds that a sequence should take to execute    |
    | 11 | `Stabilization Time`                 | Time in seconds the program will wait between sequences                     |

    <Note>
      If you need assistance with interpreting your results, reach out to the support team at [support@kodelabs.com](mailto:support@kodelabs.com).
    </Note>

    ***
  </Tab>

  <Tab title="Mixed damper operation" icon="wind">
    *This workflow will test an AHU (air handling unit) for its mixed air damper operation.*

    1. First, we display the initial conditions of the equipment.
    2. Then, KODE performs pre-condition checks to ensure the equipment is ready to be tested.
    3. Once confirmed, KODE will open the mixed air damper and route 100% outdoor air to the air-handling unit.
    4. Finally, KODE will close the mixed air damper and route 100% return air to the air-handling unit.

    <Check>
      **Outcome:** This test evaluates an AHU's capability to regulate mixed air temperature by modulating the mixed air damper.
    </Check>

    <Tip>
      **Recommended schedule:** Run monthly per AHU. Run when there are comfort complaints in a space or floor. Run when AHUs are installed and/or reprogrammed.
    </Tip>

    <Info>
      **Point requirements:**

      | Device | Required points                                                                                |
      | ------ | ---------------------------------------------------------------------------------------------- |
      | AHU    | Discharge Air Pressure, Outdoor Air Temperature, Mixed Air Temperature, Return Air Temperature |
    </Info>

    ### Required pre-conditions

    1. *AHU Discharge Air Pressure* exceeds `AHU Minimum Discharge Air Pressure Threshold`

    **Variations:** There is a variant of this workflow that works with AHU outdoor air dampers instead of mixed air dampers.

    ### Workflow overview

    **1 Pre-Condition Check**

    * *AHU Discharge Air Pressure* exceeds `Discharge Air Pressure Minimum`

    **2 Open Mixed Damper**

    * **Control:** Command *AHU mixed air damper* to `Open Mixed Air Damper Command`
    * **Success:** *AHU Outdoor Air Temperature* - `Open MAT-OAT Differential` ≤ *AHU Mixed Air Temperature* ≤ *AHU Outdoor Air Temperature* + `Open MAT-OAT Differential`

    **3 Close Mixed Damper**

    * **Control:** Command *AHU mixed air damper* to `Close Mixed Air Damper Command`
    * **Success:** *AHU Return Air Temperature* - `Close MAT-RAT Differential` ≤ *AHU Mixed Air Temperature* ≤ *AHU Return Air Temperature* + `Close MAT-RAT Differential`

    ### Tuning parameters

    | # | Parameter                        | Description                                                                      |
    | - | -------------------------------- | -------------------------------------------------------------------------------- |
    | 1 | `Discharge Air Pressure Minimum` | Minimum AHU discharge air pressure required for the test to begin running        |
    | 2 | `Open MAT-OAT Differential`      | Differential between MAT and OAT for Open Mixed Damper test to run successfully  |
    | 3 | `Close MAT-RAT Differential`     | Differential between MAT and RAT for Close Mixed Damper test to run successfully |
    | 4 | `Open Mixed Air Damper Command`  | Percentage command to open the mixed air damper to allow 100% outdoor air in     |
    | 5 | `Close Mixed Air Damper Command` | Percentage command to close the mixed air damper to allow 100% return air in     |
    | 6 | `Min Sequence Duration`          | Minimum length of time in seconds that a sequence should take to execute         |
    | 7 | `Max Sequence Duration`          | Maximum length of time in seconds that a sequence should take to execute         |
    | 8 | `Stabilization Time`             | Time in seconds the program will wait between sequences                          |

    <Note>
      If you need assistance with interpreting your results, reach out to the support team at [support@kodelabs.com](mailto:support@kodelabs.com).
    </Note>

    ***
  </Tab>

  <Tab title="VFD operation" icon="gauge">
    *This workflow tests an AHU (air handling unit) for its variable frequency drive (VFD) operation. It verifies the AHU is running, confirms the unit is maintaining pressure at setpoint, then raises and lowers the duct static pressure setpoint to confirm the VFD responds correctly.*

    <Check>
      **Outcome:** This test verifies an AHU's VFD can track duct static pressure setpoint changes in both directions.
    </Check>

    <Tip>
      **Recommended schedule:** Run monthly per AHU. Run when there are pressure or airflow complaints. Run when AHU VFDs are installed, replaced, or reprogrammed.
    </Tip>

    <Info>
      **Point requirements:**

      | Device | Required points                                            |
      | ------ | ---------------------------------------------------------- |
      | AHU    | Duct Static Pressure Sensor, Duct Static Pressure Setpoint |
    </Info>

    ### Required pre-conditions

    1. *AHU Occupancy Mode* is `Occupied`
    2. *AHU Duct Pressure* exceeds `0.4psi` \[Pressure Min Threshold]
    3. *Duct Static Pressure Sensor* is within `5%` \[Relative Tolerance] of setpoint

    <Warning>
      If any of these conditions are not met, the workflow stops and the test is archived.
    </Warning>

    ### Workflow overview

    **1 Pre-Condition Check**

    * Verify device is `Occupied`
    * *Duct Pressure* exceeds `Pressure Min Threshold`
    * *Duct Static Pressure Sensor* within `Relative Tolerance` of setpoint

    **2 Raise Duct Static Setpoint**

    * **Control:** Command *static pressure setpoint* to `Relative Modulation` above current setpoint
    * **Success:** *Static pressure sensor* reads within `Relative Tolerance` of new setpoint

    **3 Lower Duct Static Setpoint**

    * **Control:** Command *static pressure setpoint* to `Relative Modulation` below current setpoint
    * **Success:** *Static pressure sensor* reads within `Relative Tolerance` of new setpoint

    ### Tuning parameters

    | # | Parameter                          | Description                                                                          |
    | - | ---------------------------------- | ------------------------------------------------------------------------------------ |
    | 1 | `Relative Modulation` \[20%]       | Percentage to change the setpoint from its current value                             |
    | 2 | `Relative Tolerance` \[5%]         | Percentage tolerance between sensor and setpoint after the change to confirm success |
    | 3 | `Nominal Tolerance` \[0.1psi]      | Absolute tolerance between sensor and setpoint after the change to confirm success   |
    | 4 | `Pressure Min Threshold` \[0.4psi] | Minimum duct pressure required for the test to begin                                 |
    | 5 | `Reaction Time` \[300sec]          | Time to wait for actuators to complete their action                                  |
    | 6 | `Stabilization Time` \[60sec]      | Time to wait for the system to stabilize after a command and conditions are met      |
    | 7 | `Measure After` \[60sec]           | Time in seconds to wait before checking feedback readings                            |

    <Note>
      If you need assistance with interpreting your results, reach out to the support team at [support@kodelabs.com](mailto:support@kodelabs.com).
    </Note>
  </Tab>
</Tabs>

## Next steps

<CardGroup cols={2}>
  <Card title="VAV workflows" icon="fan" href="/products/ftt/vav-workflows" arrow={true}>
    Explore the VAV workflow library for damper, heating, and airflow tracking tests.
  </Card>

  <Card title="FCU workflows" icon="thermometer" href="/products/ftt/fcu-workflows" arrow={true}>
    Explore the FCU workflow library for fan, heating, and cooling tests.
  </Card>

  <Card title="Heat pump workflows" icon="flame" href="/products/ftt/hp-workflows" arrow={true}>
    Explore the heat pump workflow for combined heating and cooling tests.
  </Card>

  <Card title="FTT projects" icon="folder-kanban" href="/products/ftt/projects" arrow={true}>
    Assign workflows to devices and schedule automated testing.
  </Card>
</CardGroup>