Central Unit vs Window Unit

I use my central unit two months max per year.

Is it worth it to buy a window unit for the bedroom rather than running the central unit entire night?

The house has four bedrooms and only one or two need to be cooled at night. I would buy
two 8000 btu units.

I read that window units are not that much more energy efficient since the entire house is still warm. Can someone confirm?

Thank you

 

Window units would probably fill in for night time use. You just need to consider how long it would take to cool the rest of the house in the morning when cooling was needed.

 

In the day time, I would use the central unit.

What would be the differences in costs?

 

It would be pretty tough to figure out comparative prices.
We'd need to know heat gain and losses in the house.

There would be the cost of the units.... possibly requiring additional power wiring.
The central air would run all day and then be shut off at night so that the one or two small units could be used to keep the bedrooms cool. Then the small units get shut off in the AM and the central unit gets restarted.

When I think this thru.... it may not be cost effective to run smaller units in the bedroom and let the house get warm.

 

Window units combined with a fan to circulate the air can be very efficient; they will cool areas more efficiently than a central ducted unit.

You should never need more than a 6,000-Btu/hr window unit for a bedroom.

I cool the entire first floor with a 6,000-Btu/hr window unit & a large fan to circulate the air throughout all the rooms; & the top floor with another one.

My summer-time electric bill is extremely low.
When I have to run the basement dehumidifier - it is the big electric user...
My home is ALL electric in summer, propane furnace in cold weather.

Set the central system so the home does not get too warm; in many northern climates the rest of the house will cool-off during the night so there would be no major heatload to deal with in the morning.

 

Awesome! Thank you!

Awesome! Thank you!

 

HVAC, What is the size of the above place?