FCU Cooling

FCU Cooling

This workflow will test an FCU for its cooling operation. 

  1. First, we display the initial conditions of the equipment. 

  2. Then KODE performs precondition checks to ensure the equipment is ready to be tested. 

  3. Next we will stop heating by commanding the hot water valve to 0%.

  4. Then we will stop cooling by commanding the chilled water valve to 0%.

  5. Finally we will command the chilled water valve to 100% to start cooling. 


Outcome 🎯

This test will check a FCU’s ability to deliver cooling when the valve is set to 100%. 

Recommended Schedule 📅

  1. Run weekly per floor

  2. Run when new FCUs are installed and programmed.


Device 

Point Requirements 📌

FCU

FCU Fan % Cmd

FCU Occupancy Cmd

FCU Chilled Water Valve Command

FCU Hot Water Valve Command

AHU

Discharge Air Pressure

Required Preconditions

1.

FCU Occupancy = Occupied

2.

FCU Fan Cmd% > 5%

3.

Chiller Diff Pressure > 10 PSI  


*Variations

  1. TBD - w/ and w/o fan operation (?)

Workflow Overview


Test Step

Workflow

1

Pre-condition Check

  1. FCU is Occupied

  2. FCU Fan Cmd% > 5%

  3. Chiller Diff Pressure > 10 PSI  

2

Stop Heating

  1. Control:  Cmd Hot Water Valve to 0%

  2. Success: FCU DAT is below the threshold

3

Stop Cooling

  1. Control:  Cmd Cold Water Valve to 0%

  2. Success: FCU DAT is greater than the threshold

4

Start Cooling 

  1. Control:  Cmd Cold Water Valve to 100%

  2. Success: FCU DAT is below the threshold



                                                                         Successful Test Example


                                                                    Failed Test Example                                  

Tuning Parameters


Test Step

Result Description

1

Chilled Water Valve Close Cmd

What value do you want to cmd the chilled water valve to to stop cooling?

2

Stop Cooling DAT Threshold

The DAT must be greater than this value to confirm cooling has stopped.

3

Hot Water Valve Close Cmd

What value do you want to cmd the hot water valve to to stop heating?

4

Stop Heating DAT Threshold

The DAT must be less than this value to confirm heating has stopped.

5


Chilled Water Valve Open Cmd

What value do you want to cmd the chilled water valve to to start cooling?

6

Start Cooling DAT Threshold

The DAT must be less than this value to confirm cooling has started.

7

FCU Fan Cmd % Low Limit

If the Fan Cmd % is less than this value, the test will automatically archive.

8

Stabilization Time

How long in seconds should the program wait when one sequence finishes, before moving onto the next?

9

Min Sequence Duration

What is the minimum length of time in seconds that a sequence should take to execute?

10

Max Sequence Duration

What is the maximum length of time in seconds that a sequence should take to execute?


If you need assistance with interpreting your results, reach out to the support team at [email protected]. 


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