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TSI / Airflow LVLT

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A portable ductwork leakage tester for low velocity applications. The unit is supplied complete with a ‘Leakage Management Unit’ which gives a direct reading of the leakage rate in either imperial or metric units, flexible ducting and a duct adaptor plate.

- Tests to DW143 and DW144 class A and B ductwork

- Flow range up to 1274 m³/hr

- Portable, fits in an estate type car

Product Features

  • Document downloads
  • Instrument FAQs

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3. Select a calibration (1 available)

4. Hire enquiry details



Virtually anywhere low pressurisation is necessary, laboratory clean rooms, test cells or sealed enclosures, Airflow Leakage Testers provide a fast accurate measurement solution. The method of measuring the air flow rate is a primary standard using conical inlets directly related to ISO 5801.

Electronic speed control is provided to adjust the flow rate/pressure delivered by the unit.

The instrument is portable in the average estate car and will allow periods of testing even in arduous site conditions. The new, state of the art, LM1 Electronic Leakage Manager offers instant measurement, display and control of system performance.


Air performance at maximim air speed

354 l/s @ 500Pa, 189 l/s @ 1000Pa

1274 m3/hr @ 500Pa, 680 m3/hr @ 1000 Pa

750 cfm @ 2 ins wg, 400 cfm @ 4 ins wg

LVLT contents and dimensions

LM1 manometer, tubing, flexible ducting 3m (minimum) long with end fitting 203mm (8") diameter

Overall size - Trolley 1370mm long x 570mm wide x 600mm high

Weight 60kg

IMPORTANT NOTE - Instrument Hire Models

Instrument Hire models are supplied as a 110V versions only, and this product is not available for purchase.



Airflow duct leakage testers data sheet

  • Technical Document
  • PDF file
  • 109 KB

Airflow HVLT LVLT LM1 user manual

  • Technical Document
  • PDF file
  • 1 MB



How do you change the LM1 display to read HVLT or LVLT ?


The LM1 manometer should be supplied to correspond with the tester and will display either "LVLT" or "HVLT" when powered up.  If this is incorrect, or needs to be changed then re-initialise the LM1 as follows:

 - Hold down the 'I/M' key on the keypad while simultaneously switching the LM1 manometer on with the ON key.

-  To select LVLT press the key marked zero

- To select HVLT press the key marked light

The unit will now 'remember' the selected option, even when the unit is switched OFF, and will subsequently require just operation of the ON key to turn the manometer on.


What is the size of the flexible ducting supplied with the LVLT ?


The flexible ducting is 200mm nominal ID (8 inch).

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