HumanTechnik signolux Bedienungsanleitung Seite 50

The installation of the combined detector should not be used as
a substitute for proper installation, use and maintenance of fuel
burning appliances including appropriate ventilation and exhaust
systems.
The unit must not be opened! This can lead to malfunctions and
the warranty will inevitably expire. The batteries are permanently
installed and cannot be replaced. Protect the combined detector
from water, moisture and excessive humidity.
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