VASAIKO

PPM means parts per million — the standard unit for carbon monoxide in the air. An alarm tells you when levels reach its threshold; a monitor shows the live reading on screen, so you can watch the number itself instead of waiting for a beep.

A display-equipped monitor lets you see the current CO reading instead of relying on an alarm tone alone. The HD16 also shows combustible-gas and smoke status, temperature and humidity on its screen, without an app. This is a supplemental monitor: keep all CO and smoke alarms required by your local codes installed and maintained.

Follow the placement and mounting instructions supplied with your specific model. Keep required CO and smoke alarms in the locations specified by local codes; a supplemental monitor does not replace them. If you are unsure about a location near fuel-burning appliances, vents or moisture, check the product manual before installing it.

Cooking fumes and steam can affect sensor readings or trigger alerts. Follow the manual's placement guidance and test the device regularly. Never dismiss an alarm because the CO number looks low: smoke, combustible gas and carbon monoxide are different hazards. If an alarm sounds, follow the device instructions and your household safety plan.

Models with a charged backup battery can continue operating when AC power is unavailable. For the HD16, the stated backup time is approximately eight hours; actual runtime depends on battery condition and use. Follow the included charging and testing instructions. Never run a generator indoors or near openings to the home.

Check the listing and documentation for your exact model for its applicable certifications and warranty terms. The HD16 is tested to UL 2034, UL 1484 & UL 217 standards, with a stated 2-year warranty and 5-year CO sensor life. This is a supplemental monitor, not a substitute for the UL-listed alarms required by state or local code. Keep your required alarms installed and maintained.