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depends where you live, temp and how humid it is inside and out, age and condition of unit, freon level etc etc.
 

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Discussion Starter · #3 ·
depends where you live, temp and how humid it is inside and out, age and condition of unit, freon level etc etc.
I live in south Louisiana and the temp. is in the mid 90s with high humidity. The unit/house is 10 years old and freon is full. gauges show 75 and 240
 

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You need to check delta T ( temperature difference between return and after coil ) normally 20F.

-Your house has temp 85F. You should be able to get 65F at register, if the ducts aren't gaining any heat. As soon as the house temp getting down the temp at the register will get down also.
 

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65, I get 48 at my vents, regardless what the outside temp is.

WOW you leave your house at 65f.....you really like cool :whistling2:
 

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45 degrees to max 58 degrees is what you should get at the supply registers. This is providing your system was sized correct for 105 to 110 degree condensing temperature, and your condenser is cleannnnnnnnnnnnn.

One problem that is really showing up because of the extremely hot weather we have been having are dirty condensers. Even though they dont look dirty on the surface of the fins you will find deep in the fins the dirt has accumulated and increases the head pressure, the suction follows thus reducing the capacity of the system.
A good biodegradeble condenser cleaner should be used to clean the coil.
 

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I live in south Louisiana and the temp. is in the mid 90s with high humidity. The unit/house is 10 years old and freon is full. gauges show 75 and 240
No way to know if your system is low on charge or not with just pressure readings. Would need to know SH and SC to know.
 

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Thaw would indicate an air flow well under 400 CFM.
You have no way of determining a system cfm through the Internet. If in reply to what my output temp is on my vents, trust me, my system was properly sized, and the cfm is correct for both heating & cooling. As for the OP problem, who knows without placing hands on the unit, what their problem is. First thing I would be looking at is insulation of the house, weatherstripping, caulking, etc, before I would even say that their system is not running correctly. Especially on the Internet.
 

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You have no way of determining a system cfm through the Internet. If in reply to what my output temp is on my vents, trust me, my system was properly sized, and the cfm is correct for both heating & cooling. As for the OP problem, who knows without placing hands on the unit, what their problem is. First thing I would be looking at is insulation of the house, weatherstripping, caulking, etc, before I would even say that their system is not running correctly. Especially on the Internet.
If you getting a 48°F supply air temp with your house temp at 72°F no matter how hot it is outside. I can easily, and accurately say you are not moving 400CFM per ton. Weather I am at your house, or 1500 miles away on the internet.

A 24°F delta, ain't gonna happen at 400 CFM per ton, when its 95°F outside, and the indoor temp is 72.
 

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Beenthere, again my system works as it was designed, and again you have no way of diagnosing a system on the Internet in how it was designed. Rest assured, my system works within the spec's that it was designed, and runs as it should, regardless what the indoor & outdoor temp is.
 

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Beenthere, again my system works as it was designed, and again you have no way of diagnosing a system on the Internet in how it was designed. Rest assured, my system works within the spec's that it was designed, and runs as it should, regardless what the indoor & outdoor temp is.
Don't believe I said anywhere that it isn't working as designed. Just said your Not moving 400 CFM per ton.

Since you say its working as designed. how much air is it moving? How much air was it "designed" to move?

PS: We regularly diagnose HVAC systems over the internet on a daily/hourly basis.
 

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It is set up at 890 1st stage, 1435cfm in 2nd stage, as it was designed to do, per the manufacturer spec's (Lennox signature series, model G61PV-36B-70). btw, thought that we were talking about helping the op, not diagnosing my system.
 

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Since you posted these AMAZING values.....we wanna know how your designed system work. :thumbsup:
 

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It is set up at 890 1st stage, 1435cfm in 2nd stage, as it was designed to do, per the manufacturer spec's (Lennox signature series, model G61PV-36B-70). btw, thought that we were talking about helping the op, not diagnosing my system.

We are talking about helping him. You used you system's delta as a reply to him. Now he may think his should do the same, when it probably shouldn't.



You didn't list your A/C/condenser model. Is it a 3.5 ton condenser.
 
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