AC on the 2nd story of your house (West: houses, neighborhood)

[jhilde101]

I saw 2 new posts about temps and ac settings so I thought I would start another post on the subject.
We have a 2 story house WITH solar screens on the front of our West facing home.
Our ac is set at 78 during the day upstairs and does not shut off. We set it at 73 during the night and it will cycle on and off. The upstairs unit is 15 yrs old. I am in the market for a new unit.
Anyhow, does anyone with a 2 story house have the same issue as us where your upstairs unit runs ALL day long?

TIA,
J

[MckinneyOwnr]

Our house faces West as well. We have our upstairs set to 77 (76 from 1pm to 4pm when the baby is napping) and it cycles on and off normally.

Our house was built in 2008, we have radiant barrier, and 2x6 construction, so more insulation in the walls than a 2x4 built home.

At 15 years, that unit is about at the end of its usable life, and it certainly not as efficient as units built today. You may also benefit from laying additional insulation in your attic, and upgrading your windows with energy efficient ones. I'd also check for any leaks in your ducting, in my parents old home, they had two back bedrooms that never seemed to cool very well... Turns out that one of the ac ducts was completely disconnected in the attic and was just blowing cool air into the attic!

[MurphyPl1]

Yes, because heat rises and that unit ends up doing all the work.

And in our neighborhood the builders put the big AC for the downstairs with a smaller unit for the upstairs. It should really be the other way around.

[jhilde101]

that is how ours is too. Bigger unit downstairs and smaller unit up. This is our 3rd 2 story house and all 3 have been the same.
Do you think it will still run all day long with a brand new ac unit for our 2nd floor?

[Johnhw2]

Mine is a story and a half. The upstairs unit is 3 or 4 tons cooling 1700 SF. It's an original unit now 16 years old. The big downstairs unit is 5 ton I believe and it has been replaced three times now. Go figure? I have another 3 ton unit downstairs taking care of the master, study and guest bedroom down. It too is an original unit like the upstairs one.

Makes me wonder if that size in that year of constructin was np better built to run.onger or why the larger one has been replaced now three times.

[MurphyPl1]

Originally Posted by jhilde101

that is how ours is too. Bigger unit downstairs and smaller unit up. This is our 3rd 2 story house and all 3 have been the same.
Do you think it will still run all day long with a brand new ac unit for our 2nd floor?

Yep. Because it will still be doing the bulk of the cooling for the house.

[MckinneyOwnr]

Originally Posted by jhilde101

that is how ours is too. Bigger unit downstairs and smaller unit up. This is our 3rd 2 story house and all 3 have been the same.
Do you think it will still run all day long with a brand new ac unit for our 2nd floor?

If it's sized correctly, no, it should NOT be running constantly. My downstairs main ac and the upstairs ac are the same size. We set the downstairs ac one degree cooler than upstairs, to help even out the fact that hot air rises. Since we have an open floor plan, the downstairs air we keep 1 degree cooler than upstairs, and as such, both units run for very similar amounts of time during the day.

My two story houses (built from 2005 on) have all had the same size ac for 1st and 2nd floor.

AC's are sized according to the square footage they are expected to cool. If your upstairs is significantly smaller than the downstairs, then you will have a smaller unit. But if both floors are relatively the same size, the ac units should be, too.

[Rakin]

A very important question is....... Have you had your AC units serviced lately?

You may be low in Freon. (or other problems)

[Johnhw2]

Can you check for freon and other problems by measuring the air temperature coming off the coils or vents and compare it to the room temperature at the air intake? I think the temperature drop should be about 20 degrees at least across the coils.

If your unit is running all day and not cooling down to under 80 you have an issue with the unit. Freon being low is a very common problem that creates your situation.

[6oo9]

My upstairs is set at 73 and it does not run all night long. I went to the balcony and I saw wind turbine vents on my roof.