Timberwolf, don't expect your warranty to hold up if your unit does not. It is NOT a recommended idea. The duty cycle is rated on 10 minutes. The thing is, if you exceed the duty cycle, the unit should cool for 15 minutes before restarting. We are not alone in this, even "on demand" units recommend this time span to deal with residual heat. Pushing close to the duty cycle theoretically should only need 4 minutes, but depending upon a lot of variables, that time could be longer. Just because the heat is lowered in the cooling sinks, doesn't mean the heat is gone in the power circuits yet.