The Consumer Product Safety Commission said the heaters pose a fire hazard as some were manufactured without the required switch, which shuts down the heater in the event of a unit failure.
The heaters were made by Lennox Industries Inc. of Richardson, Texas, and by ADP of Granada, Miss.
They were sold nationwide from September 2003 through April 2011 for between $2,700 and $4,200.
The heaters involved in the recall include ADP FOA series heaters with model numbers FOAN-60-1-1-1, FOAN-100-1-1-1, FOAP-100-1-1-1 FOAN-125-1-1-1, and FOAP-125-1-1-1.
Consumers were advised to stop using the heaters immediately and contact ADP for an inspection and repair.
Consumers can call 866-303-8634 for information.
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