Undersized central air unit - upgrade or get portables - which is cheaper in the long run?

Question

I have a brand new 2000 square foot manufactured home with many south facing windows and so-so insulation. I was given a 4.5 ton central air unit that is not cooling properly if the days are in the 90s or 100s and frequently freezes over.

Would it be cheaper in the long run to 1) buy a larger unit or 2) install portables in the back bedrooms that stay the warmest?

Is it possible to sell or trade in our current unit?

Answer 1

4.5 ton unit should be enough for your sq. ft.. If the unit is freezing over it may be low on Freon, otherwise it needs proper servicing. Don't think about more equipment till you get what you have fixed.

Answer 2

If you do have a four and a half ton,a five is not going to make you any happier.There is something wrong with you existing a/c.You have more than enough tonnage.Something else is wrong.

I wouldn't spend money on small units for the back bedrooms either.Just find out what's wrong with your a/c.

I had a 1800 square foot manufactured home in the mid 90's and I had a four ton cooling it and never had any cooling issues.Except when the compressor went out once because of lightening.

EDIT:

I've been steady running service calls,doing load calculations,and estimates since 1986.

I am sorry that you don't agree but there is a problem with your existing unit.Somewhere.

Answer 3

I agree with the above. Your central unit is not working properly for your home. It is more than enough size wise. A  unit is properly sized for your home. Bigger is not better.  An improperly sized unit will cause many problems such as short cycling, humidity and condensation, etc. Get with a reputable company to see if they can determine if the unit is undersized or installed improperly.