Thanks Aaron for your reply! I have 5 foot flex watt heat tape, according to the manual of the heat tape it is 8 watts per foot, then I cut 3 foot then set aside to my incubator all in all I have 24 watts, this was on early as March 10 when I first test my incubator, on March 10, I finally decide to put another 2 foot heat tape to increase the temp but nothing happen.

How do I know the power percentage?

In our country we used normally 220 volts in our appliances, but this thermostat made from yours are 110 volts, I'll used transformer to run this system.

Thanks!