Use the @Pressure Key to Get More Exact Results

Get Exact Results with the @ Pressure Key

The @ Pressure feature allows the DM‑2 to extrapolate airflow (or leakage) results at a precise target pressure—even if the actual pressure hasn’t been reached. It’s ideal for leaky buildings or systems where hitting the setpoint is tough.

How It Works

Activate Set Mode

Use Set Pressure (or Set Speed) to establish your target test pressure (e.g., 50 Pa).

Approach the Target

Run the fan until you’re within about 10% of the setpoint (e.g., 45–55 Pa).

Press @ Pressure

The gauge switches from showing actual flow to extrapolated flow at exactly your target pressure (e.g., CFM @50 Pa). Press again to return to current flow display.

Toggle and Adjust

In Set Pressure mode, each keypress toggles between:

Actual flow
Flow @ default pressure (e.g., 50 Pa)
Flow @ newly set pressure (e.g., 75 Pa), if changed via Set Pressure

Benefits of Using @Pressure

No need to reach exact pressure: Get valid results even if the system can’t hit your target directly
Enhanced stability: Extrapolated readings are less erratic than raw values
Efficiency: Save time by avoiding excessive fan adjustments, while still getting point-precise data

When to Use it and When Not to

Best Use Case: Actual pressure is within ±10% of target (e.g., 45–55 Pa for a 50 Pa setpoint).
Results remain accurate and valid.
Avoid if you’re far below your target (e.g., only reaching 20 Pa); extrapolation becomes unreliable.

Quick Step Guide

Step	Action
1	Press Set Pressure → input target (e.g., 50 Pa)
2	Run fan until you’re close (within ~10%)
3	Press @ Pressure to view Flow @50 Pa
4	Press again to toggle back to actual flow
5	Hold only briefly — toggle as needed during test