I bought this heater two weeks ago and have used it 4 times. Yesterday we turned it on while eating our lunch. After about 10 minutes it stopped working. I checked all breakers and the outlet. All looked fine, I hit the on switch and the lamp came on again. It lasted a few minutes and again cycled off. I tried the switch again and it wouldn't come on but, after about five minutes I tried the switch again and on went the heater. That occurred a couple of more times exactly the same way. This morning I turned it on and it has been going for about 40 minutes just fine without cycling off. I'm just not sure what to expect now and will wait to see before calling on the warranty. When the product is on, it is exactly what we wanted for our patio situation. I guess my review would be five stars if I was sure of it's reliable function going forward!