testo 324 leakage measuring instrument - Pressure/gas leak detector

Order-Nr.  0632 3240

  • All-round measuring instrument for legally compliant testing on gas and water pipes

  • Leak tightness checks of gas pipes according to TRGI 2018 and liquid gas pipes according to TRF 2012

  • Intuitive and legally compliant menu navigation

  • Software-based creation of test reports

  • Instant calculation of pipeline volume

  • Safe operation thanks to the single-hose connection

testo 324. Pressure and leakage measuring instrument


Product Description

testo 324
Pressure and leakage measuring instrument DVGW-approved for all tests at gas and water pipes as load and tightness test and serviceability test

Delivery Scope

testo 324 pressure/leak detector, rechargeable battery, calibration certificate.

Technical Data

Temperature - NTC

Measuring range

-4° to 212 °F / -20 to +100 °C

Temperature - Type K TC

Measuring range

-40° to 1112 °F / -40 to +600 °C


±0.9 °F or ±0.5 %

Absolute Pressure

Measuring range

240 to 460 InH₂O / 600 to 1150 hPa


±1 InH₂O / ±3 hPa


to 480 InH₂O / to 1200 hPa

Leakage measurement

Measuring range

0 to 10 l/h


±0.2 l/h or ±5 % of mv


0.1 l/h

Pressure measurement

Measuring range

0 to 400 InH₂O / 0 to 1000 hPa


±0.2 InH₂O or ±3 % of mv / ±0.5 hPa or ±3 % of mv

Pressure measurement (external probe)

Measuring range

0 to 363 psi / 0 to 25 bar


±0.6 % Fs (0 to 145 psi) / ±0.6 % fs (0 to 10 bar)

±0.6 % Fs (> 145 to 363 psi) / ±0.6 % fs (> 10 to 25 bar)

Pipe volume calculation

Measuring range

max. 1200 l


±0.2 or ±5 (1 to 200 l)

General technical data


480 InH₂O / 1200 hPa


38 oz. / 1070 g


11 x 4 x 3 in. / 270 x 90 x 75 mm

Operating temperature

41° to 104 °F / +5 to +40 °C

Protection class

IP40 acc. to EN 60529

Additional probe sockets

2 Hirschmann sockets for connecting pressure and temperature probes

Gas connections

2 pressure connections DN 5

DVGW permit according to 5925

Instrument class L up to volume = 200 litres

Display type

Colour display, presentation of graphic curves

Data transfer

USB, IRDA, Bluetooth® (option)

Battery life

approx. 5 h measurement time, mains operation possible

Storage temperature

-4° to 122 °F / -20 to +50 °C



Connection cable.

Order Number: 0430 0143

Quick-action surface probe

Order Number: 0604 0194

High-pressure probe up to 362 psi

Order Number: 0638 1748



Leakage test on gas pipes (leak and load test)

The technical regulation for gas installations (in short: TRGI) is a binding and at the same time important regulation for skilled trade. The TRGI governs how gas installations are to be planned, designed, serviced and maintained. This applies to all gas installations. This regulation is taken care of by the German Association for Gas and Water (DVGW). The TRGI 2018 is the current version. Amongst other things, this states that gas pipes are to be tested according to the construction phase (basic shell, completion, and repairs). The following inspections particularly play a role in the application stated here:

Load testing
During testing, the material is tested for stability and the connections for service life; this takes place prior to plastering over or concealment of the gas pipes. During load testing, the newly installed pipe, without fittings or gas appliances, is put under 1 bar pressure. The testing medium is air or inert gas. There must not be a drop in pressure during the test, which lasts at least 10 minutes.

Leak test
This test is for checking the pipe for leaks, without fittings and gas appliances. The measuring instrument must not register a drop in pressure during the minimum 10 minute testing period (depending on the system volume); the test pressure is 150 mbar (previously 110 mbar).

Leakage test on gas pipes in the boiler room

A gas installation set up according to the legal provisions of the German Association for Gas and Water (“DVGW”) and the TRGI 2018 is the prerequisite for proper, long-term operation. However, while in operation, operating conditions or other general conditions may affect the safety of the gas installation. Technical systems are subjected to wear and contamination in their daily use. Only an expert can identify, assess and repair these kinds of safety-related changes. The leak test (or more aptly, serviceability test, also known as leakage measurement) for the pipeline system is to be repeated every 12 years using a measuring instrument and recorded in a test results report. The operator thus has a technical expert report. Some buildings insurers include these inspections and certificates/reports in their general insurance terms. For the serviceability test or leakage measurement, the gas pipe is always tested in operating conditions/with operating pressure (no increased test pressure). During this test, a measuring instrument detects whether gas is leaking from the pipe and how much.

Measuring pressure on burners (nozzle pressure, gas flow pressure, etc.)

Standard readings taken during services of domestic heating systems include checking the gas pressure on the burners. This involves measuring the gas flow pressure and gas resting pressure. The flow pressure, also called supplied pressure, refers to the gas pressure of the flowing gas and resting pressure of the static gas. If the flow pressure for gas boilers is slightly outside the 18 to 25 mbar range, adjustments must not be made and the boiler must not be put into operation. If put into operation nonetheless, the burner will not be able to function properly, and explosions will occur when setting the flame and ultimately malfunctions; the burner will therefore fail and the heating system will shut down.

Measuring pressure and leakage on water pipes

The testo 324 has been developed for professional applications in everyday work on water pipes. All relevant elements for the measurement are combined in one instrument.