New to AC, need guidance please

Old 06-26-06, 10:40 AM
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New to AC, need guidance please

We bought the house in July last year and this is the first year we have experience with AC, so please help me understand if my system is working OK.

The house is 2500 sqf and is South West facing with no shade, so it gets pretty hot outside. The AC is a Trane 1100, I think it is about 5 years old

With temp hovering at 100 degree outside, the AC cannot bring the temp down to below 79, with the airflow in some room very low. Is this normal? What is an acceptable temp for a house AC when it is working fine, I mean if I set the temp at say 75, should a good system be able to give me this temp?

Also on the control board, there is a button showing FAN/AUTO.
If I switch to FAN, will it just be the fan that is running or will it work with the AC as well.

Many thanks for all your help
Old 06-26-06, 10:55 AM
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I dont know alot...but I did stay at a holiday express last night.

It is difficult to say if your unit is working correctly with he info you have given, but there are a few things you can check first to determine if there is a problem.
1. When was the last time you changed the filter?
2. When the system is running, go outside to the compressor unit and feel the large copper pipe going from it to the house. It should be cool, and if there is an area that is not covered by should be wet with condensation.
3. Can you see your ductwork?...if you can, check it for leaks, or if it is in the attic, make sure something that has been tossed up there hasnít damaged a duct.
4. Has the system ever been serviced since you have had the house?, a good condenser cleaning may be in order.

As to the second part of the question, if you switch the fan from Auto to ON, the fan will run continuously. If the Unit is also set to cool, the AC will cycle on and off as normal.
So yes, you can run the fan all the time, and the rest of the unit will come on and off as needed.
Old 06-26-06, 01:54 PM
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Steve covered it all for you. Just like to add. Most contract 's for a AC job will say something like it will cool the home 15o or 20o below outside temp is all.

It also helps if you can have shades on the windows to the south and west. Let the unit run.if it cools down some dont open the home up again . It takes about 5 to 7 days for a AC to get the humidity Out of a home this is when you start to feel cool at 78o.

Old 06-27-06, 04:43 PM
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New to AC, need guidance please


Thanks so much for replying.

I haven't changed filter since we moved in and although it does not seem like it needs it, I am going to change it anyway and see if it helps.
I did check the copper pipe outside as Steve suggested and found that all the pipes are insulated, the only exposed area is the connection point to the AC unit and the metal there feels cold, but no condensation.
Will check ductwork next, it;s all under the house in the crawlspace (3 ft clearance).

What would be the air temp at the outlet if I put a thermostat there?
Also does the fan draw a lot of electricity?
If I do have the condenser cleaning done, what would be a reasonable charge?

Sorry about all the questions but I do appreciate your help.
Thanks again

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