What You'll Learn

• What airflow data to record during every test
• Why proper airflow documentation matters for baselines, warranties, and quality verification
• How the airflow_source field in measureQuick tracks measurement method
• How to document before-and-after airflow for test-in/test-out workflows
• How to include airflow findings in customer-facing reports
• Photo documentation practices for airflow test setups

What You'll Need

• Device: iPhone (iOS 15+) or Android phone (Android 10+) with measureQuick installed
• Account: measureQuick account with active subscription
• Camera: Phone camera for documenting test setup and conditions
• Prerequisite knowledge: TrueFlow measurement (M1) and report generation (J1)
• Time: 10-15 minutes to read; documentation adds 5-10 minutes per test

What to Record

Every airflow measurement should be accompanied by enough context that another technician, or you six months later, can understand what was measured, how, and under what conditions.

Required Data Points

Record these for every airflow measurement:

1. Total system CFM. The measured airflow through the system, entered in measureQuick's airflow field.
2. CFM per ton. Calculated from total CFM divided by system tonnage. measureQuick calculates this automatically when airflow and system profile data are both present.
3. Measurement method. TrueFlow Grid, capture hood, duct traverse, nozzle, or estimation. measureQuick tracks this in the airflow_source field.
4. TESP at time of airflow measurement. Total external static pressure should be measured during the same test session as airflow. Airflow and static pressure are linked; recording both gives a complete picture.
5. System operating mode. Cooling high stage, heating, fan-only. Airflow changes with operating mode on variable-speed systems.
6. Filter condition. New, clean, loaded, or dirty. A dirty filter reduces airflow and increases TESP. Note the filter MERV rating and size.
7. Blower speed setting. Relevant for PSC motors with selectable taps. ECM motors adjust automatically, but note if the system was in auto, low, medium, or high speed mode.

When Measuring Individual Registers

If you perform room-by-room measurement (M6), also record:

• CFM at each supply register, labeled by room
• Return grille CFM if measured
• Whether all registers and doors were open during measurement

Why Documentation Matters

Baseline for Future Comparison

An airflow measurement today becomes a reference point for every future visit. If a system measured 1,150 CFM on installation and reads 900 CFM two years later, the decline points to a specific problem: dirty filter, dirty coil, failing blower motor, or duct damage. Without the baseline measurement, the 900 CFM reading has no context.

measureQuick stores airflow data with each test. When you create a new test on the same project, the historical data is available for comparison.

Warranty Support

Equipment manufacturers increasingly require documented commissioning data for warranty claims. Airflow measurement is a core commissioning parameter. A warranty claim that includes measured CFM, TESP, and the measurement method is stronger than one without airflow data.

Quality Verification

For companies that perform installation and commissioning, airflow documentation proves the system was set up correctly. This protects the company if a comfort complaint arises later. The test-in record shows what was measured and verified at the time of installation.

Regulatory and Program Compliance

Some utility rebate programs and building codes require documented airflow measurement for new installations or equipment replacements. Proper documentation in measureQuick provides the evidence needed for compliance.

The airflow_source Field

measureQuick tracks how the airflow value was obtained using the airflow_source field. This field is recorded automatically based on how the data enters the app.

The distinction matters for data quality. A trueflow measurement is a direct, calibrated reading. An estimated value is a calculation with wider uncertainty. A manual entry could be any accuracy level depending on the method used, but measureQuick has no way to verify the source.

When you enter a manual value from a nozzle test (M7) or a traverse (M4), the airflow_source field records it as manual. Add a note in the project notes specifying the actual method. This way the data quality is clear to anyone reviewing the test later.

Before-and-After Documentation

Test-In: Establishing the Baseline

The test-in measurement captures the system's condition before any work is performed. For airflow:

1. Measure total system CFM with the system in its as-found condition.
2. Record TESP at the same time.
3. Note filter condition, blower setting, and any obvious duct problems observed.
4. If individual register measurement is part of the scope, measure room-by-room CFM.

Do not change anything before the test-in measurement. The purpose is to document the starting point.

Test-Out: Verifying the Improvement

After making corrections (filter replacement, coil cleaning, duct repair, blower adjustment, damper balancing), measure airflow again:

1. Measure total system CFM under the same operating conditions as the test-in.
2. Record TESP.
3. Note what changed (new filter, cleaned coil, adjusted dampers, etc.).
4. If room-by-room measurement was done on the test-in, repeat it on the test-out to verify distribution improved.

measureQuick's paired test analysis (test-in vs. test-out) compares the before and after results. The improvement in CFM, CFM per ton, and TESP is visible in the paired comparison.

Including Airflow in Customer Reports

measureQuick generates customer-facing reports that summarize the test findings. Airflow data appears in the report when it is recorded in the test.

What to Include

• Total system CFM and CFM per ton, with the target range (350-450 CFM/ton) for context.
• TESP, with the manufacturer's maximum specification for comparison.
• Pass/fail status for the airflow subsystem if measureQuick flagged it.
• Before/after comparison if both test-in and test-out were performed.

How to Present It

Homeowners do not think in CFM or inches of water column. When discussing airflow results:

• Frame CFM per ton as "your system is moving X% of the recommended airflow." A system at 300 CFM per ton on a 3-ton unit is at 86% of the 350 CFM minimum.
• Frame TESP as "the resistance in your duct system is above/below the manufacturer's limit." This connects the measurement to something the homeowner can act on (filter change, duct repair).
• If airflow improved after service, quantify the improvement: "Airflow increased from 950 CFM to 1,180 CFM after cleaning the evaporator coil."

The report should state facts. Let the measurements tell the story.

Photo Documentation

Photos add context that numbers alone cannot provide. Take photos of:

1. The TrueFlow Grid installed in the filter slot. This documents that a direct measurement was taken, not just an estimate.
2. The filter condition. A photo of a dirty filter communicates the problem to the homeowner more effectively than a pressure drop number.
3. The DG-1000 or manometer display showing the TESP reading during the airflow test.
4. Duct conditions if duct problems are found: disconnected boots, collapsed flex, open joints.
5. The equipment data plate to confirm system tonnage and blower specifications.

Store photos in the measureQuick project. They become part of the permanent record for that service visit.

TrueFlow Grid measurement grid showing the internal sensor array structure

Tips & Common Issues

Forgot to record TESP during the airflow measurement

TESP and airflow should be measured during the same blower run. If you measured airflow but forgot TESP, take the TESP reading before changing anything (filter, blower speed, operating mode). If conditions changed between measurements, note the discrepancy.

Airflow data shows as "estimated" when I expected "trueflow"

Verify the App-to-App transfer completed. If the TrueFlow App sent the data but measureQuick did not receive it, the app may have fallen back to the enthalpy estimate. Check the TrueFlow App for the last transmitted reading and re-send if necessary.

Customer asks what "good" airflow looks like

The standard target is 350-450 CFM per ton for cooling. Below 350 reduces cooling capacity and can cause evaporator icing. Above 450 reduces dehumidification in humid climates. For heating, targets vary by equipment type. Frame the answer around their specific system and the measured result.

Test-in and test-out were measured at different blower speeds

This invalidates the comparison. If the blower speed changed between measurements (manually or due to ECM programming), the airflow difference reflects the speed change, not the service work. Document the blower speed for both measurements and note the discrepancy.

Related Articles

Prerequisites (complete these first):

• TrueFlow Grid Measurement Theory - How to obtain measured airflow data
• Report Generation - How to create and customize customer reports

Follow-up articles (next steps after this one):

• Troubleshooting Low Airflow - What to do when documented airflow is below target
• Airflow Imbalance Analysis - Documenting room-by-room airflow distribution

Related in other domains:

• Total External Static Pressure - TESP measurement to accompany airflow documentation
• CFM per Ton - Target airflow ranges and why they matter
• TrueFlow Grid Setup - Setup for the most common direct airflow measurement

Need Help?

If you get stuck or this article does not answer your question:

• Check the Related Articles section above
• Contact measureQuick support: support@measurequick.com