WÖHLER DP 700 - LEAKAGE MEASUREMENT

Wöhler DP 700 - air system leak test

Increasingly higher demands are being placed on the energy class of ventilation systems. The tightness of the ventilation technology plays a special role in this. There is great potential here if the air flow rate with low leakage can be adapted to the current requirements. In the future, it will be increasingly important to take into account the leakage of the air system. The recommended measurement is therefore becoming increasingly important.

• Leakage measurement according to ČSN EN 12599 - Ventilation for buildings - Test procedures and measurement methods for acceptance of installed ventilation and air-conditioning equipment
• tightness measurement according to ČSN EN 14134 - Ventilation of buildings - Performance testing and installation checks of residential ventilation systems
• measurement of tightness class according to ČSN EN 13779 Ventilation of non-residential buildings - Basic requirements for ventilation and air-conditioning systems according to ČSN EN13779-2010-07, ČSN EN 1507, ČSN EN 12237, ČSN EN 13403 as well as ČSN EN 13180
• meets high accuracy requirements according to ČSN EN 1751 and ČSN EN 15727 for measuring individual components (± 0.0009 l/s)
• with adapter for measuring range less than 0.3 l/s
• easy to use
• optional automatic or manual sequential measurement
• possibility of separate differential pressure measurement
• indication of the measured value in any units without manual intervention
• measurement protocol - printout directly on site on a thermal printer (optional accessory)
• Handy kit in two suitcases, easy to transport

DP 700 usage options

• Leak testing with a large leak measurement range: from individual components to complete systems with an area of 100 m²
• Leakage testing of air conditioning, climate chambers, heat exchangers, distribution cabinets and other enclosed spaces
• room tightness test
• practical and laboratory measurements of building components (e.g. OSB boards, windows)
• can be integrated into final inspection in series production with optional program control (control via USB port from PC)
• with reduced capacity (40 l/s) usable with 110 V, 60 Hz

Measurement principle

Leakage inspection of ventilation and air conditioning systems according to ČSN EN 12599

Due to the availability of a leak test, this check should be carried out during the installation phase. The leak test is carried out in accordance with ČSN EN 13779, which defines leak classes A to D. In order to carry out this test, the systems are divided and sealed into individual parts. The leak test device then produces an overpressure using a fan in appropriate sealed sections of the supply air line, and a negative pressure in the exhaust air line, which should be in the middle of the average operating pressure if possible. As a standard, + 200, +400 or +1,000 Pa is assumed as the overpressure, -200, -400 or -750 Pa as the negative pressure. The flow volume required for this corresponds to the air leakage depending on the internal surface and the test pressure, these limits are specified in the relevant standards. The user selects the test pressure and enters the internal surface. The device automatically detects air leakage based on the area and pressure, then classifies the system into a leak class.

Leakage testing in series production of air systems

Quality documentation in series production is still very important. The test can be carried out in parallel without major disruption of production within a few minutes. It is performed on square pipes and fittings, and deviations from the standard are determined using a vacuum test. The test object is only briefly placed on the test plate and covered with a loose lid.

Checking the tightness of residential ventilation systems according to ČSN EN 14134

Checking the tightness of residential ventilation systems is similar to checking the tightness according to ČSN EN 12599. The leak should be measured at at least three points at a pressure difference of around 20 Pa, 60 Pa and 200 Pa. From today's perspective, measuring with three different pressures is no longer absolutely necessary; this standard dates from 2004 and is currently under European revision.

Technical data

Scope of delivery

• Wöhler DP 700 - air system leak test
• measuring air hose 3.75 m
• measuring air hose 4 m to adapter
• measuring pressure hose 10 m
• calibration protocol
• 2.5 m network cable
• adapter 0.3
• 2 brass nipples
• hose connectors for vacuum measurement
• filter
• silicone oil
• 2 transport cases