wa8yxm wrote:
The problem with mobile homes is they are fairly well sealed.
Don't know what mobile home you are talking about but all the ones I have been in, the wind whistles right through them as if the thing was made of Swiss cheese.. Had water lines freeze that were in the middle of the trailer inside interior walls and near the furnace closet for insult to injury. Had to cut holes in the walls to allow heat to get to the lines which helped some.
As far as the OPs question, unless the drier is gas fired (OP said no cord came with it which means it is a 240V electric drier and not gas fired) it will most likely be fine with no "make up" outside air.
Supplying outside air may help the drier work a bit easier expelling the hot moist air outside when installed in a very air tight shell home. However bringing in extreme cold outside air in winter and hot humid air in summer can affect how long it takes to dry the loads.
If you don't feel comfortable in not following manufacturers instructions then add the outside air.