oversized. Now what?

[brewyourown]

Probably won't be that accurate,and if you lower the cfms too much ,you can damage the the equipment,i.e. Compressor.

It also won't show any air the is lost thru supply duct leakage,and you need 350 cfm per ton across the coil.

Since it appears to be oversized,this may not help as much as is needed.

I just counted in my head, I have 10 registers and 1 return in the house. Does that mean on average I am getting (if set up properly) 105CFM per register? If so, does that sound like a lot of air flow, not enough air flow, or just the right air flow?

[beenthere]

If they are all the same size, but different lengths, you are not getting the same air flow from each.

Even the same lengths don't have the same air flow most of the time.

[brewyourown]

If they are all the same size, but different lengths, you are not getting the same air flow from each.

Even the same lengths don't have the same air flow most of the time.

yes, but on average, that is the flow each would receive if the fan is set up to the correct speed. Some maybe getting 135CFM, some may be getting 80 CFM, my question is whether this range of CFM seems "in the ballpark" or whether it seems high, low?

[beenthere]

The 1050 would be enough air for a 3 ton A/C.

But doubtfull your getting that total through those 10 supplies.

[brewyourown]

also, as an FYI, when I do a set back during the day, basically have the system off all day until get home, I can bring the temp from 81 or 82 inside to 75 inside in like an hour and a half to two hours. However, the system usually has to shut itself off once or twice prior to reaching the set point on the t-stat. It can usually run close to 45 minutes to an hour continuously prior to having to shut itself down for 5 or 10 minutes, then turns on again to get down to the set point.

Does this mean anything, or is it normal operation.

[beenthere]

Thats not normal operation.

Something not quite right.

If I let my place get to 80, and then turn the stat to 70, it will run non stop till it reaches 70.

[brewyourown]

The 1050 would be enough air for a 3 ton A/C.

But doubtfull your getting that total through those 10 supplies.

I forgot, I do have some air leakage in a basement register. Basically, a previous home owner put a pretty large register on the main ductline facing downward to heat a portion of the basement space during winter. The register is closed but does not prevent all the air from coming out, so there is some leakage of air out of the register even when it is closed b/c it is old and doesn't close very well anymore.

[brewyourown]

Thats not normal operation.

Something not quite right.

If I let my place get to 80, and then turn the stat to 70, it will run non stop till it reaches 70.

this is my dilemma in a nutshell. There is something not quite right with the system, it is oversized, etc...

BUT, the house is comfortable, the wife never complains and the house is nice and cool in the summer.....

So I don't know whether to spend money and time to fix it or just leave well enough alone....

[beenthere]

Measure your humidty in the house.
if its close to 55%RH.
Then a proper sized A/C,HP, will remove more humidity, and perhaps allow you to set the stat higher, and save money on your cooling bill.

You must determine when and where you want to spend your money.
And how much to who.
The oil company. The electric company.

[trebor1065]

What should his humidity be reading?

[beenthere]

55% or lower. At 55, your on the high end of normal human comfort level.

In my place. 72°F and 48%RH feels cooler then 68°F and 55% RH.

[brewyourown]

55% or lower. At 55, your on the high end of normal human comfort level.

In my place. 72°F and 48%RH feels cooler then 68°F and 55% RH.

I keep the house at 75 degrees except at night I turn down to 74 or 73 degrees depending. The RH is between 55 and 60%. This morning, it measured 65% at 74 degrees. Is 75 degrees to high a setting for AC?

[trebor1065]

I keep the thermostat at 72 F with a relative Humidity reading of 49-50% this is on the first floor, the second floor the humidity falls in around 53%.
I think my unit is slightly oversized but I have learned to live with it.