The answer to 'what size carbon monoxide detector do I need' is that the size of the carbon monoxide (CO) detector you need depends on the size of your home. Generally, you should install one CO detector for every 1,000-3,000 square feet of living space. Larger homes may need multiple detectors placed strategically to ensure coverage throughout the home.
When choosing a CO detector, look for one that is certified by Underwriters Laboratories (UL) and meets the latest safety standards. The detector should have a digital display to show the CO levels, and it should be placed at least 15 feet away from fuel-burning appliances like furnaces, water heaters, or fireplaces. This helps ensure the detector can accurately measure the CO levels in the surrounding air.