The Manufactured Housing Forums

We just purchased a new Homes of Merit MH and the instructions that come with the fireplace say not to use "fake" logs like Duraflame. Why is that???

My guess is that all the wax would cause overheating (in the stove trade, "overfiring.") Eventually that may break down the firebrick and/or chimney.

Because if they contain wax this can build up in the flue and posssibly cause it to ignite.You can use fake logs if they don't contain wax(check the label)The heat from duraflame logs(what little there is) has nothing to do with it,a wood fire would generate 'much' more heat.
If you use wood don't use pine.There full of sap and can cause buildup and fires in the chimney.Burn a hardwood such as oak.

True for any fireplace really. Avoid wet or soft woods as well - that's how chimney fires start. Stick with oak and maple and other hard woods.