Testo 420 Capture Hood

The Testo 420 Capture Hood is a professional airflow measurement instrument featuring flow straightener technology and Bluetooth connectivity for precise HVAC air balancing. This capture hood connects to measureQuick for real-time airflow data streaming, automated balancing documentation, and comprehensive system diagnostics on both supply and return registers.

Accurate Airflow Measurement

The Testo 420 capture hood uses flow straightener technology to deliver accurate airflow measurements on both supply and return registers. Unlike basic capture hoods that can be affected by turbulent airflow at the register face, the Testo 420's straightening grid ensures consistent, repeatable readings. The hood measures CFM directly, eliminating the need for manual calculations or correction factors. The lightweight design and ergonomic handle reduce technician fatigue during room-by-room air balancing.

measureQuick Wireless Integration

When connected to measureQuick via Bluetooth, the Testo 420 streams live airflow readings directly into the app's air-side diagnostic workflow. measureQuick records CFM measurements at each register, calculates total system airflow, and compares results against equipment design specifications. This integration turns room-by-room air balancing from a manual clipboard exercise into a connected, documented diagnostic process.

measureQuick reads the Testo 420 in two modes. In hood mode it records airflow in CFM at each register. In pressure-only mode the 420 works as a manometer, and measureQuick records its pressure readings.

Air Balancing and System Diagnostics

Airflow measurement is fundamental to HVAC system performance. The Testo 420 combined with measureQuick enables technicians to verify that each room receives its design airflow, identify undersized or restricted ductwork, and document improvements after duct modifications. For service companies pursuing ACCA Quality Installation verification or NCI Air Upgrade certifications, the Testo 420 provides the measurement accuracy that these programs require for credible airflow documentation.