Solution to negative pressure problems

Savo PEK-1 differential pressure switch solves negative air pressure problems caused by cooker hoods.


Ministry of the Environment updated the National Building Code of Finland in the beginning of 2018 and now it is imperative that ventilation systems compensate the air removed by cooker hoods and cooktop extractors. This means that the ventilation system needs to know when the cooker hood is on. This information can be relayed to the ventilation system with a separate differential pressure switch.

If the exhaust air is not properly compensated the result is negative air pressure in the apartment which can cause weakened extraction of cooking vapours and suction of replacement air from wrong places. Air trapped inside the walls of the house can seep in through cracks and openings and bring health hazards such as microbes and mold spores – for example actinomycete that smells like root cellar.

Savo PEK-1 differential pressure switch detects when the airflow (m3/h) in the exhaust pipe is bigger than the set value. When a cooker hood is switched on, air begins to flow in the exhaust pipe and the more it flows, the bigger the static pressure difference inside the pipe and the ambient room. The differential pressure switch’s sensor measures this pressure difference and when the set value (for example 100 Pa) is exceeded, the relay contact inside of the pressure switch closes, and this information is transferred to the ventilation system so that it takes in more replacement air and reduces the exhaust air. Savo PEK-1 differential pressure switch enables potential free relay contact information for almost every cooker hood installation.

Read more about the product at:

Savo Pek-1 paine-erokytkin