Electric space heaters are a cheap way to chase away the chills—and they don't come much cheaper than the $25 Optimus H-5210 sold at major retailers like Amazon, Sears, and Walmart. But it was the only electric heater in our tests of 19 models that set our test cloth on fire. We contacted Optimus, and test results it sent us also showed a potential safety problem with this model. It claims to have fixed the problem on 2012 models. But we bought our heaters, 2011 models, in early summer, and there is no way to tell the model year from the box.

In Consumer Reports tests of space heaters, we put terry cloth over a heater to see whether its sensor shuts it off before it overheats. Though manufacturers, including Optimus, warn against placing heaters near flammable materials, we think it could easily happen in a typical home.

We've judged the Optimus H-5210 a "Don't Buy: Safety Risk" as a result and are asking the Consumer Product Safety Commission to recall it. If you own this model, stop using it and ask the retailer for a refund.