Icubator and tub temperatures different?

I got a new PVC incubator this weekend. I do not have a clutch of eggs to put in it yet but I decided to test it and get it setup. I set the herpstat to 89F and waited about an hour. The incubator itself is 89F but inside the shoe box size tub was only 85F. Should I wait longer, raise the incubator temps? Is this normal?

Is the tub just plain empty? Fill it with media and water and watch the temps rise ;)

Normal. It will take a while for the tub to get up to the desired temperature :-)

Keep working out the kinks and get everything just right before the eggs go in :gj:

They are empty. Would wet paper towel work for the testing part of it?

Just give it more time. It will heat up.

I just checked on it with adding the paper towel, and it has actually gone down to 83F. I will leave it on through out the night and see if it changes.

Test it like you are going to use it ;)

I have tubs with media and water bottles sitting in the incubator at least a couple weeks before my the eggs drop so that the vermiculite and water are already up to temp. Two reasons. When when the eggs drop, I just add the water to the tubs and they're good to go. Also if I am going to be hatching multiple clutches, then I won't be putting cold tubs into the incubator and having it cool down while the new tubs come up to temp. It's all about stable temps and anything you can do to keep the swings to a minimum is better.

My incubator and egg temps never match. I have my incubator set up at about 89 before the eggs go in. Once they are in I wait a few hours and check temps directly on the eggs with a heat gun. Then tweak my temps after about 12 hours. Too cool is much better then too hot.

This morning my temperatures were still different. Incubator at 89F and the tubs at 85F. I raised the incubator temps to 92F and after a few hours the tubs with wet paper towel was 90F. I lowered the incubator to 91F and we will see from there.