Hello,

I have 2300 sq. ft ranch house on a crawl space in Middle Tennessee that was built in 2004. There is a bonus room over the garage which is typically warmer in the summer than the rest of the house...no surprise there. We have 1 3.5 ton unit for the entire house. There are 2 vents in the bonus room and 1 14x30 return at the top of the stairs. There is 1 other return for the system in the hallway by the other bedrooms.

This is our first summer in this house so I don't know any history on how it cooled last summer, but this year the AC tends to run all day after it gets hot outside. It usually is still running around 10 or 11PM after we've had a hot day. The house usually feels cool, but the thermostat is usually around 77 or 78 at it's hottest part of the day - we usually have it set at 74. We have been conscious of keeping the blinds/curtains closed during the day in order to keep some heat out.

I have had an HVAC company come and check it out about a month ago and they ended up adding a little freon. Otherwise, they said it all checked out good.

I am curious if adding a hotel style AC in the bonus room would help the the main unit out with keeping the rest of the house cooler. It seems that since the air being pulled into the return in the bonus room is warmer than the air downstairs, that the unit would then be distributing this warmer air around the house and also not be able to pull the temperature down as much as it could if it were only pulling air through returns in the main portion of the house.

I'm curious if anyone else has added a mini split unit or other type of AC to their bonus room and seen any benefit to the rest of the house.

 

Have you washed the condenser and evaporator coils?

 

Yes, we have cleaned the condenser coils outside, but I don't think they cleaned the evaporator coils when they were there doing the "tune up."

 

They are really happy with it because they can control the temp precisely in the new room. Plus the system is highly efficient, saving a fair amount of energy. After shopping around, they went with Mitsubishi. The only downside was the initial expense, but they plan on recouping some of the cost as time goes by.

 

Do you know if they saw an improvement in the other parts of their home in regards to cooling?

 

I'm not certain if it eased the strain of cooling the rest of the house, but the new bonus room is a very, very popular spot this summer!