"It is a new refrigerator."
I'm not a native japanese speaker so only from i've learnt from here (i mean i am not 100% i am correct). But it should be like this:
This refrigerator is new = この(=this)れいぞうこはあたらしいです (Note that in english, new and refrigerator are not together, so in japanese they have the particle は between them).
It is a new refrigerator = あたらしいれいぞうこです (now new and refrigerator are together in english, so for japanese it's the same).
As for the phrase "this is a new refrigerator" that Kevkingofthesea mentioned in the other comment, it's totally different and i am not sure how to say it. Maybe something like "これはあたらしいれいぞうこです” but i'm not sure about it