Safety en5pressure falls below atmospheric pressure. Toxic gases fromthe flue or the extraction shaft are sucked backed into the liv-ing space.▶ Always ensure adequate fresh air in the room if the appli-ance is being operated in exhaust air mode at the sametime as room air-dependent heat-producing appliance is be-ing operated.▶ It is only possible to safely operate the appliance if the pres-sure in the room in which the heating appliance is installeddoes not drop more than 4 Pa (0.04 mbar) below atmo-spheric pressure. This can be achieved whenever the airneeded for combustion is able to enter through openingsthat cannot be sealed, for example in doors, windows, in-coming/exhaust air wall boxes or by other technical means.An incoming/exhaust air wall box alone will not ensure com-pliance with the limit.▶ In any case, consult your responsible chimney sweep. He isable to assess the house's entire ventilation setup and willsuggest the suitable ventilation measures to you.▶ Unrestricted operation is possible if the appliance is oper-ated exclusively in air recirculation mode.WARNING ‒ Risk of fire!¡ Fatty deposits in the grease filters may catch fire.▶ Clean the grease filters roughly once a month.▶ Never work with naked flames close to the appliance (e.g.flambéing).