Lennox Hearth Products is recalling about 3,200 Shadowdance Natural Gas Log Set Burner Assemblies because a crack can develop at the gas valve connection allowing natural gas to leak while the burner is in use, posing a risk of carbon monoxide poisoning.

Lennox has received 20 reports of cracks at the gas valve connection, but no injuries have been reported.

This recall involves gas burners sold with Lennox brand Shadowdance natural gas log set burner assemblies. The product is used in a wood-burning fireplace or a ventless firebox enclosure. The assemblies were sold under model numbers LSVFSD-18, LSVFSD-24 and LSVFSD-30, and include a burner and ceramic-fiber log set. Replacement gas burners also were sold separately under model number LSVFSD-NG. Burners included in this recall have serial numbers that begin with 6407, 6408, 6409 and 6410A through 6410G. The burner’s model and serial numbers are printed on a metal identification plate attached to the burner.

The log sets and assemblies were sold at Fireplace and HVAC retailers and installers nationwide from August 2007 through December 2010 for between $700 and $850.

Consumers should immediately stop using the recalled natural gas log set burner assemblies and can contact Lennox to arrange for a free replacement of the burner. For additional information, please contact Lennox Hearth Products at (800) 299-0027 between 8 a.m. and 4 p.m. CT Monday through Friday, or visit the firm’s website at http://www.lennoxhearthproducts.com