Why does a Nighthawk smoke and carbon monoxide alarm keep chirping even with new batteries?

If a Nighthawk carbon monoxide detector chirps every 30 seconds or so, the problem likely lies with either the batteries or the wiring to the batteries. Short beeps do not indicate the presence of carbon monoxide.

Many models allow users to wire the detector to a home's electrical system; doing so can increase the longevity of batteries.

While it might be tempting to try to fix the wiring in a malfunctioning carbon monoxide detector, their low cost and the potential dangers of relying on a faulty unit mean that it's best to purchase a new unit if one is showing errant behavior.