Here’s another reason to check your smoke and carbon monoxide alarms. One-and-a-half million Kidde Nighthawk combination Smoke and CO Alarms are being recalled because they may not chirp in an emergency. Health Canada says two hard-wired models are affected – KN-COSM-IBCA and KN-COSM-ICA – one has a battery back-up, the other does not. They were manufactured between June 2004 and March 2011. You’ll have to remove the unit from its holder and check the backside of it for the date and model number. No adverse incidents have been reported in Canada; there have been eight in the U.S. Those with the recalled alarms should stop using them and can contact Kidde for a free replacement or a discount on a new alarm. The company can be contacted at 1-855-239-0490 between 8:00 a.m. and 5:00 p.m. Monday to Friday, or through its website.