There is a difference in the quality of monitors
You should know that the best monitors detect minute levels of carbon monoxide in the air, while less-expensive models available at discount and retail stores provide little or no protection until levels are beyond practical safety levels. We recommend that you invest a few more dollars to get a high-quality monitor for each level of your home. If you intend to mount the carbon monoxide monitor yourself, be sure to place it no lower than eye level. This deadly gas is lighter than the surrounding air and will accumulate well above floor level.
Even if you don’t suspect carbon monoxide problems, contact a professional for a carbon monoxide safety test. The technicians at Blue Stream also perform this test as part of your regular seasonal maintenance