V2 - AHU - Mixed Damper Operation

V2 - AHU - Mixed Damper Operation

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.


Outcome 🎯

This test evaluates an AHU's capability to regulate mixed air temperature by modulating the mixed air damper.

Recommended Schedule 📅

  1. Run monthly per AHU

  2. Run when there are comfort complaints in a space or floor.

  3. Run when AHUs are installed and/or reprogrammed.


Device 

Point Requirements 📌

AHU

Discharge Air Pressure

Outdoor Air Temperature

Mixed Air Temperature

Return Air Temperature

Required Pre-Conditions

1.

AHU Discharge Air Pressure > AHU Minimum Discharge Air Pressure Threshold


*Variations

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


Workflow Overview


Test Step

Workflow

1

Pre-Condition Check

  1. AHU Discharge Air Pressure > Minimum Discharge Air Pressure Threshold

2

Open Mixed Damper

  1. Control: Command AHU mixed air damper to 100%

  2. Success: AHU Outdoor Air Temperature - 5 ≤ AHU Mixed Air Temperature ≤ AHU Outdoor Air Temperature + 5

3

Close Mixed Damper

  1. Control:  Command AHU mixed air damper to 0%

  2. Success: AHU Return Air Temperature - 5 ≤ AHU Mixed Air Temperature ≤ AHU Return Air Temperature + 5



Tuning Parameters


Test Step

Result 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

Defines the percentage command to open the mixed air damper to allow 100% outdoor air in.

5


Close Mixed Air Damper Command

Defines the percentage command to open 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.


If you need assistance with interpreting your results, reach out to the support team at support@kodelabs.com.