It saves lives. The BRUNNER negative pressure safety control "USA" monitors the air and chimney pressure during the burn-off process. It switches off all ventilation systems, for example cooker hoods, if the pressure difference is no longer sufficient for a safe operation. In other words: tiled stoves and fireplaces can be installed and operated safely - regardless of the ventilation and air-condition technology installed in a building.
Lawmakers have been calling for a monitoring unit for the operation of manual fireplaces in dense buildings with ventilation systems or kitchen hoods. For this reason, BRUNNER has developed the negative pressure safety control "USA". It ensures that smoke and heating gases cannot flow into the living area, if the ventilation system malfunctions or when the kitchen hood is being operated simultaneously.
The air suction by systems like a tumble dryer, can be so strong, that poisonous smoke and gases like carbon monoxide are no longer drawn through the chimney, but are sucked into the living area. The life-threatining gases are not visible and usually odorless.
The USA stops the operation of all air-sucking systems, if there is a critical vacuum in the installation room. The safety switch automatically activates the system again, when the pressure level has normalised.
The USA is placed in the immediate vicinity of the facility. During the burn-off, the control unit monitors the differential pressure between the combustion chamber and the installation area. Short-term pressure fluctuations caused by wind blasts at the chimney or by the opening a window are automatically filtered out by the USA.
The protection function is the sole purpose of the vacuum sensor. Therefore, a display was deliberately omitted. The USA is easy to use and DIBt tested. A red and a green light-emitting diode are sufficient to indicate the operating state. If the red LED is lit, a clear safety risk has occurred.
For the "USA" BRUNNER relies on proven, high-end aircraft technology. The sophisticated precision mechanics are high-quality, durable and guarantee an exact and extremely sensitive measurement accuracy for many years, without replacement and maintenance work.
As an alternative to USA 3, BRUNNER has now introduced the brand-new USA 4 onto the market. Instead of the barometric pressure transmitter, a piezocrystalline pressure sensor is installed in the fourth generation of the safety control, which no longer requires calibration. This makes the USA 4 more compact and efficient - but just as secure!