Trying to find out what ton this sears a/c unit is the model# 76981604 there also was a b/n # 4157-9-224 on the tag. The sn#3804108058

I have been unable to find any Sears unit that matches these numbers.

Is this a window unit or a central heating and air conditioning unit.

Also how much space is it cooling.

It is a condensing unit. The customer say the house is 1800 sqft ,but the house looks smaller

UTL model number.

If I made a guess I would say 2 1/2 ton or less. See if you can find a model number on the evaporator coil.