Central Air Conditioner Issue

[nomrah]

It's been abnormally hot these past few days so we finally decided to give the air a run. New homeowner here, moved in a couple of weeks ago and the house is about 4 years old.

The unit doesn't seem to cool the house all that well. There's air coming out of the vents, but it's not all that cool, at least not as cool as I think it should be. The air blowing out of the vents on the first floor is decent. On the second floor it feels like it barely trickles out. Air ran for about 6 hours and only cooled the house 1 degree according to the thermostat.

Looked at the air filter and it's pretty dirty so I'll replace that, but not sure what problem that would help. I could see it maybe helping the air coming out to be colder or does it address the air not blowing very strong on the second floor? Or maybe it won't help either. Maybe the refrigerant needs recharged?

Any past experiences?

 

[Capt Caveman]

Did you have it inspected prior to buying the house?

When was the lst time it was tuned-up?

Possible that the a/c unit never was sufficient to the cool the house.

 

[Ronstang]

You need to get an AC check. If your filter is that dirty it is likely the coil is dirty also and needs a cleaning. Once that is checked and done if necessary the unit probably needs some freon. The problem with little air coming out of the vents on the second floor are likely due to a improperly designed system with crappy duct work. This might get more expensive to fix than you think. The AC is the first thing I check out on a house. It is amazing how many are improperly installed from day one when the house was built. You can blame crappy low cost AC contractors that use bottom of the barrel labor. It is amazing how many houses could be so much more efficient if their AC was just properly installed.

 

[nomrah]

Had a general house inspection and found no problems, but didn't get a specific inspection done on the AC unit itself. Not sure when the last tune up was, but I can ask the previous owner.

 

[akshatp]

If you havent ran it for 4 years, chances are you need a general "tune up" of the A/C unit and most probably a refrigerant recharge. Oh and change those filters ASAP

 

[NoShangriLa]

The dirty filter is the problem.

Make sure that your compressor and line is not freeze up due to high pressure from the dirty filter. Refrigerant line & compressor may need sometime to thaw or use a hair drier on the line to speed up the process.

Iced up system -- visible ice on the refrigerant & compressor, and/or clicking sound of ice when compressor running, or humming stress from compressor due to complete iced system.

Make sure that the blow still is functioning with out stress humming (could have burnt motor due to high back pressure).

Most new blower are variable speed therefore they should handle the back pressure well. Also, the high limit cutoff should kick in & reset every 5-15 minutes if the system were dirty and iced up.

IMHO, your AC system should be okay, and check the filter frequently (normally 3-4 months, 4-6 weeks for dirty environment) to keep up the efficiency and prolong your equipment life span.

Good luck!

 

[Gothgar]

probably filter... could be the coolant though, which wouldn't be too much to have a service done on it.

 

[richardycc]

I am having the same problem with my central AC too...I have a tech coming Tues, hopefully just need some freon.

 

[Christobevii3]

It is the freon is low

 

[Hippiewan]

First of all, change your filter. If you have the 1" wide filters, change them often, at least check if not change them every month. This is most important during the cooling season as a dirty filter can cause restriction, which causes low air flow which can cause your coil to freeze, which will cause no air flow, you get the picture. If this doesn't help, you will have to have a professional out. Really you should never be low on Freon, if you are, you have a leak, it happens but there are many more causes usually related to air flow that are more likely the problem.
Secondly, you have to understand that whole house air conditioning systems don't work like window units. You turn on a window unit, soon you are cool, central air takes more time but holds a more constant temp than window air, they are designed to be more steady but they do take longer to cool your house.
If your upstairs is consistently warmer than your main floor, you probably do not have enough return air ductwork on your second floor, this seems to be pretty common anymore, sadly, and about the only solution would be to add more ductwork to the second floor.
I hope you get it worked out, most modern duct systems are not properly designed, the contractor brings in whoever is cheapest and not the person that knows what they are doing and talking about and then it becomes the homeowners responsibility. Sad but true.

 

[jmcoreymv]

We had the same problem in our house. We'd set the thermostat low, but the air wouldn't get any cooler. A year later we realized we didn't have an actual AC unit.

 

[Quiksilver]

Sounds like the Freon coolant stuff is low, I just had it refilled at my house like 3 days ago with same type of problems; AC would kick on, blowing air but not 'cool' air. Also replacing the air filter would probably help too.

 

[bctbct]

Originally posted by: jmcoreymv
We had the same problem in our house. We'd set the thermostat low, but the air wouldn't get any cooler. A year later we realized we didn't have an actual AC unit.

lol

 

[Shawn]

Refrigerant is probably low. Get it checked.

 

[NoShangriLa]

Depends on the lay out of the house and the design of the ductwork, return air doesn?t need to be on all floors. If the return air duct & opening is correctly size; the system should function just fine with only 1 return air opening/line.

If there is consistent cooling problem on the second floor, then the supply line to that area and/or the return is partial block. Make sure the dampers are open if the ductworks have them.

You can?t rule out low refrigerants, because any system can develop leaks.

I have installed brand new heatpump and found that there is a factory defect leak at first leak test & trial run. And, it was a pain in the arse to remove because I have to remove the connecting ductworks & refrigerant line & install a new machine in its place.

 

[Mrvile]

Wow...I appreciate how real the replies are to an "air conditioning problem" thread.

Good work, ATOT.

 

[nomrah]

Thanks for all the replies, I'll get that filter replaced asap and see how it goes.

 

[Iron Woode]

Originally posted by: Mrvile
Wow...I appreciate how real the replies are to an "air conditioning problem" thread.

Good work, ATOT.

it could be a mouse.

 

[Saint Nick]

If a mouse runs out... it might be unhealthy!!

 

[SpazzyChicken]

You mentioned that you have a 2-story house....do you have two separate AC units or a single one? If you look outside your house do you have two units or one?

If you only have one, there may be a manual damper that needs to be opened to feed more air to your second floor. Open in the summer to allow more cold air and closed/partially open in the winter as you don't need as much heat upstairs. It should be labeled (hopefully), but if not, look for the main duct coming off the plenum that feeds the upstairs vent. It should have a lever that opens and closes the damper.

Plenty of other good advice here, but I thought I'd add that as it hadn't been mentioned. Easiest bet would be to call an AC service company to come take a look. They'll be able to diagnose the problem and tell you all you want to know about the system. If it's 4-years old and you're not sure it's ever been serviced, it's worth the $$$. You don't want to have to replace that any sooner than necessary, big time $$$$$$$

 

[Uppsala9496]

Make sure that the outside AC unit is actually running. You could just have the furnace fan running.

I had this issue a couple weeks ago. It was a bad fuse on the outside box leading into my place. Replaced the bad dual element fuse and everything is fine now.

 

[xboxist]

Originally posted by: jmcoreymv
We had the same problem in our house. We'd set the thermostat low, but the air wouldn't get any cooler. A year later we realized we didn't have an actual AC unit.

I lol'd

/clap

 

[Rubycon]

If the filter is dirty change it! Also if possible to see the evaporator coil check it as it may be dirty. Reduced airflow reduces efficiency and in severe cases may damage your compressor due to excessive liquid flowing back through the suction line to the compressor. (if unit is not equipped with a suction accumulator and summer only AC units are usually NOT)

 

[markgm]

Low refrigerant. I had my 3 year old unit recharged for the second time. The guy thinks there is a microscopic leak in the evaporator, which will run me around $700 to replace. Joy. I love issues I can't fix myself.