Access Configuration Manual

Heat pump as using flammable refrigerants i.e. R454B, it is need for safety function to evacuate the gas inside AHU, if the system has a leakage. It is two Gas sensors for detection inside the AHU, supply air side and extract air side. Gas sensors is connected to the Access control unit. Gas sensor alarm forced the running mode to Gas evacuation mode (normal speed levels) even if the running mode is stopped. Air gas sensor mixture decreased, lower than alarm limit, Gas evacuation mode runs in minimum 2h, than is the Gas detector alarm possible to acknowledge and AHU can be stopped. A safety damper module is used in the end of Supply air stream, and in the beginning of extract air stream, to block the air in to the building. The air going through the evacuation damper to the air from supply air part to extract air part and then blowing out through the exhaust air.