No it is in the unit. It is reasonably accurate however only about 5% high which is actually a bit better than expected. It set the unit to 60% and the room goes to about 65% but the enclosures are on the far wall so they are a bit lower 60-63% I like it the issue is the filler cap is easy to get cross threaded and it needs to be cleaned often, but they all do so that is just the way they work. I really like this one. (owned 4)