Your vent-free gas heater, logs, fireplace and stove require periodic maintenance to burn clean and operate as designed. Failure to perform maintenance can lead to soot build up around the product as well as smells, Please have the following actions performed to ensure trouble-free use. The primary air inlet holes allow for the proper amount of air to mix with the gas to provide a clean burning flame. These inlet holes should be kept clear of dust, dirt, hair and lint. The air inlet holes need to be cleaned prior to each heating season. We also recommend that burner tube and pilot assembly be kept clean and free of dust, dirt, hair and lint.