Window Air Conditioner Installation, Maintenance, Repair FAQs

Q&A on Window A/C Units

Window AC Air Flow or Fan Speed FAQs

My window A/C unit fan speed is too high - how can I adjust it ?

HI there, The lowest fan setting on my window A/C is way too high. It blows like a hurricane.

Is there any way to adjust the settings to make "low" really "low"? Carrie

Reply by (mod) - DF

Carrie,

I'm doubtful that you can, at reasonable cost, change out the factory-installed fan speed control on your window A/C unit as long as the original one is operating to factory spec.

But you can try adjusting the air-directing louvers to not blow the hurricane where it's not wanted, or even to leave them partly closed to slow down the air flow.

It's possible that your window A/C unit is over-sized for the cooling load in your home.

You can compare your window's BTUh cooling capacity with the size of the area being cooled by looking at this

PORTABLE AIR CONDITIONER BTU CHART for portable room air conditioner BTU sizing advice.

If your unit is too big, not only might it make the room too cold or unevenly-cooled, it may also fail to dehumidify the space properly.

If you don' think the unit BTU capacity is too great, try closing the louvers on the outlet openings on your A/C unit. It may still be a bit noisy but you'll cut the air flow rate.

Window / Through-Wall A/C Condensate FAQs

Window air conditioner condensate is draining into the house

My a.c. unit was removed for window replacement. When we began to use the unit the condensation water ran inside the house.

So we turned it off for a few days. When we tried to turn it back on, it would not come on at all.

Does the fact that it was improperly installed cause it to go out? - by M Shows -

Reply by (mod) -

M Shows

I don't know what may have been done to your AC unit - for example if it were removed and stored on its side or upside down that could give you some trouble (refrigerant leaking into a capillary tube).

The fact that water ran inside your house suggests that when the AC unit was reinstalled it was not properly sloped to drain to the outdoors.

That problem alone wouldn't explain the total loss of operation.

I'd look first at the circuit to be sure it's on and that you're using the on-unit controls properly. (For example, trying to turn on the window A/C by a remote control if the remote's batteries are dead could fool you into thinking the problem is the unit.)

Then if the unit won't turn on I suspect that due to having been stored on its side, liquid refrigerant flowed into the compressor motor, causing it to seize. If that happened the unit is beyond economical repair.

Before tossing it out, you might check with local A/C or appliance repair shops to see if they'll give you a repair cost estimate if you drop the unit by yourself.

See details about troubleshooting and fixing window A/C unit condensate handling

at CONDENSATE HANDLING for WINDOW/WALL A/C UNITS

 

Through-wall A/C condensate disposal by evaporation?

My boss seems to think through the wall A/C's at out hotel are supposed to evaporate instead of condensate outside , is this true? by Anonymous

Reply by (mod) -

Anon I don't know what you've got installed but if it's a conventional refrigerant-operated air conditioning system the condensate that is produced needs to be properly disposed-of.

There are indeed condensate evaporation systems used on some refrigeration equipment but that's not a feature I've found on through-wall air conditioners.

Watch out: if the condensate from your units leaks back into the building or down into the building walls it risks creating an expensive health hazard: mold contamination; and if the condensate is dripping onto a walkway it's can become a hazard to pedestrians as well as a building code violation.

Which way should the window air conditioner slope to drain properly?

When installing a window unit does the front have to be slightly facing downward in the back a little bit up or is it the opposite way for correct draining? - Nicole farris -

Reply by (mod) - slope the window AC down at its outside end to drain properly

Nicole

We install the window air conditioner such that the outdoor end of the unit is tipped slightly downwards.

This helps a sure that the condensate that the unit produces will drain out of the unit and to the outside rather than draining into the building interior.

Window AC unit spits water

i have a window AC unit (4 years old) that "spits" when it is running. what can I do to fix this issue? thanks. - by Jody

Reply by (mod)

Often there is so much condensate in an air conditioner that water droplets are picked up by the blower fan and blown out of the unit.

Check first to be sure that the unit's condensate drain is not blocked.

Window & Through-Wall A/C or Heat Pump Unit Brand/Model Identification

(Data Tags)

How do I find the Brand and Model on my window A/C unit

I have a window/wall mount A/C unit that needs to be replaced.

The only markings I can find (above a bar code) 71EX0880 S/No.701TADR13986

Need to know brand, and specs to replace.

When I search either number on Google, nothing comes up. - Jen

Reply: look for a manufacturer's data tag giving model and serial number and brand. OR ...

Jen:

Perhaps a more careful look at and inside the equipment at data tags, labels, markings will help track down the brand and model of your AC unit.

Some illustrations are at DATA TAGS on AIR CONDITIONERS

If there is no manufacturer's data tag anywhere inside the unit it's unidentified, but ...

Really? You don't need that data in any case if you are simply going to replace a window or wall air conditioner.

You would choose a replacement unit whose cooling capacity was adequate for the space you need to cool in your particular cooling climate.

See this PORTABLE AIR CONDITIONER BTU CHART for portable room air conditioner BTU sizing advice and match that to your room size.

 

Window A/C Repair / Maintenance FAQs

Do window air conditioner motors need to be oiled?

Can you oil motors on ac units? and is there a certain type of oil ? Thank you, Andrea

Reply by (mod) - Most residential window A/C equipment does not require oiling

Most residential window or through-wall A/C equipment does not require oiling by the consumer.

Some components in the air handler of central air conditioning or heat pump systems such as the blower fan bearings, and some commercial unit motors that expect oil to be added at bearings using an oil specifically formulated for electric motors and so labeled.

For example, the next time you're in your local hardware store in the oil section take a look at the old standby 3-in-1 oil -you'll see a red-labelled can for the traditional product and a blue labeled can marked "for electric motors".

How do I clean dirty fins on my window AC unit

I have a very old window a/c unit that still works but needed a deep thorough cleaning. I'm not sure how to clean all of the mold & dirt out of the coils because these aren't the fin type.

They look more like fuzzy aluminum pipe cleaners.

It's a 230v 18500btu mfg. by JC Penney Corp. In 1979 & have yet to find any material or info about it- aside from random Craigslist ads where people are selling one of these beauties with the faux wood-grain front grill.

I've used 4 cans of coil cleaner & the hose after taping off or disconnecting electrical items & motor.

Any help would be appreciated, since I'm unable to buy a new one & it's already hit 107 in N. Calif this year! Leigh Chancey

Reply by (mod) - the "dink factor" tells us when to stop fooling around with the A/C unit

Leigh

The evaporating / cooling coil you describe is, I agree, a bear to clean. Where justified a professional would remove the unit, take it to a workplace outside, and probably use a combination of a coil cleaner spray and modest water pressure to clean the system, since gravity alone won't de-muck those "pipecleaner" fins.

If you want to look further, details about cleaning the fins on the evaporator coils of an air conditioner can be found at

DIRTY HVAC COIL CLEANING PROCEDURES 

and at

SPLIT SYSTEM AC MOLD CONTAMINATION REMOVAL 

But indeed a salient question in any job is when to quit, arguing you've done the right amount of messing around.

When and how to apply the dink factor to cleaning your A/C unit

My partner in HVAC repair Carol Schnierer, who never said a foul word in her life, used the term "Dink" where I might use a stronger verb.

She referred to "dinking around with ...." stuff and explained a critical concept to me - the DINK FACTOR.

The dink factor is the ratio of improvement (from dinking around with something) to harm (from dinking when you should have quit).

So you're installing a piece of wallpaper and it's almost perfectly placed. You push on it one more time and RIIIIP it tore. You dinked too far. The dink factor went below 1.

Quit dinking around with your air conditioner before you damage it -

DINK FACTOR = IMPROVEMENT / HARM should always be = 1 or greater.

When the dink factor approaches 1 you're about to do more harm than good - that's when to quit.

How often do I need to add refrigerant to my window A/C unit?

Someone told me that the refrigerant in my air conditioner needs to be replaced? How long does refrigerant gas last? Does it get used up? by Anon

Reply by (mod) - never - unless there is a leak in which case first find and fix the leak

Anon,

An air conditioner does not consume refrigerant; so your question about how many years the refrigerant will last needs to be re-stated.

If your system has a leak the leak needs to be found and fixed before the unit is recharged.

Window A/C Frost or Ice Problem FAQs

Ice on the coils of a window air conditioner

Hi, the window air conditioner I'm working on shows ice formation on the evaporator coils.

It started to around 2 to 3 coils then it gradually increases until almost the entire coils are covered with ice.

I won't go with the idea that the thermostat should be set in a way to avoid the compressor running continuously because before the trouble begun the unit has been running almost continuously for 8hours for the last several years and there was no occurrence of ice/frost build-up.

We check the unit current and its ok, so we believe the charge is also ok.

We check other possible causes, like distorted coils fins, dirt, obstructions and blower speed and they seem to be all ok. What do you think should I do more? - Arnie

Reply:

Arnie no way can I be smarter than a trained service tech, but

The most common causes of air conditioner evaporator coil frost or ice formation are

1. A dirty air filter, blocking airflow across the coil or, more subtle, very dirty squirrel cage fan blades that also drastically cut air flow across the coil

Is the blower fan itself dirty? This one can fool you.

Dirt on squirrel cage blower fan blades fills in their curve and really cuts airflow

Those details and an example from a system we inspected are

at BLOWER FAN ASSEMBLY CLEANING

2. Low refrigerant because there's a refrigerant leak to find and fix. (The tech often can determine this by some careful temperature measurements)

Diagnosis and repair details are at FROST BUILD-UP on AIR CONDITIONER COILS

Question 1 - how did you figure that he charge is ok vs the actual possibility that the refrigerant is low?

Question 2 - While this isn't something you can easily check yourself, and while it's much less common on a window air conditioner, it's possible that your system has a partly crimped or blocked capillary tube - its refrigerant metering device.

If there is no refrigerant leak, a clogged capillary tube can result in the low side pressure in the system being abnormally low, uneven refrigerant metering;

How does that happen? A blob of oil or dirt traveling in the system easily blocks a cap tube as its internal diameter is quite small..

Finally, if your system has ever been serviced such that someone had to cut a refrigerant line, a filter/drier installed after that repair could be clogged .

Daniel Friedman

Window A/C Installation & Safety FAQs

Is additional support necessary when a thru-the-wall a/c unit sleeve is used?

Is additional support necessary when a thru-the-wall a/c unit sleeve is used? - by Anonymous -

Reply by (mod) -

Anon:

Good question. As Tampa Florida Mark Cramer, a home inspector and educator (and my friend) says, "...it depends"

Certainly I have seen thousands of through-wall A/C units with no additional support protruding out through apartment building walls. In those cases the metal sleeve or "box" into which the actual A/C unit slides is fastened to properly-constructed framing in the building wall.

An add-on opening for a through-wall A/C unit sleeve, if properly constructed, would also be secured to the building wall framing and would provide enough support.

But if someone did not properly install and secure the sleeve to the structure or for some large, heavy units, added support in form of an exterior bracket may be needed. Indeed IN inspected such an installation that had sagged enough to cause leaks into the building wall cavity.

See details and our safety warnings at

WINDOW / WALL A/C SUPPORTS

Where to buy a replacement cage for my LG air conditioner

i have a small LG air conditioner in my front window and I need a small cage, where can I find one? by Anonymous

Reply by (mod) -

Sorry I don't understand what cage you need.

If you mean the squirrel cage blower fan, that is a part you'd want to get from LG directly, or possibly from your local HVAC repair supplier.

Window A/C Noise FAQs

Window air conditioner makes a ticking noise

My 'window air conditioner' makes a kind of ticking, clicking, 'dink' sound.

It almost sounds like theres a little pellet in there that is flying around and hitting the sides. (I don't know).

Its not like a hard thump or clanking.

Its driving me crazy. It'll be quiet for a while, then it randomly starts with the noise. What could be the problem? - Mandy

Reply by (mod)

Usually a regular ticking sound in an air conditioner, if heard when the unit is running, is traced to a loose or failing blower fan - a round rotating "squirrel cage blower fan" assembly.

On occasion I've found that the fan blades were hitting a loose wire or even a small stick that fell into the A/C unit from outdoors.

That's something you might be able to see yourself if you're handy enough to pull the air conditioner forward out of its mounting sleeve - otherwise you'll want help from a repair person.

See more examples and diagnosis and repair details for A/C unit clicking or ticking noises found at

• CLICKING SOUNDS from air conditioner or heat pump systems
• FAN NOISES, HVAC

Question: Clicking noise at window A/C unit at the top of the compressor

I cleaned my A/c wall unit today. Since it doesn't cool anymore I gave it a good cleaning. Once it dried up. I installed it back. Ran it for awhile. But, noticed on top of compressor was making a clicking noise every five seconds. - Mike

Reply by (mod) -

Mike

That sounds as if there may be an electrical problem, possibly a relay trying to start a seized compressor motor.

If the compressor motor is shot the unit fan may run but you won't see any cool air.

A simpler problem could be a rotating fan part hitting an obstruction.

Watch out: if a moving part cuts a wire the unit becomes unsafe and may risk electrical shock or a fire.

 

Window A/C Unit Operating FAQs

Wall Unit A/C cycles on 2 minutes, off 4 minutes

My air conditioner wall unit runs for like 2 minutes then shuts off for 3-4 minutes then goes back on for two minutes.

Any idea what's wrong? - Eileen Hoof

Reply by (mod)

That sounds like an abnormal short-cycling air conditioner unit;

Before digging into the controls or into an electric motor failure, I'd check to be sure that the unit's filters are clean.

A blocked filter could be causing overheating in the unit that in turn causes it to turn itself off.

More diagnosis and repair suggestions are

at SHORT CYCLING AC COMPRESSOR

 

What is causes my air conditioner motor to overheat?

My a/c motor overheats; why is that? - by Phil -

Reply by (mod) - Here are some reasons an A/C motor may overheat include

Phil

Some reasons an A/C motor may overheat include

- bad or worn bearings at a fan or other motor in the unit

- loss of lubrication; if overheating is in the compressor motor its bearings may be shot or seizing

- running on low voltage

- bad start capacitor for the compressor motor

 

Window AC won't stop until I turn it off

My window AC automatic turn off and on system not working, its running continuously until I manually turned it off. Tell me how to fix it. by jzee -

Reply by (mod)

When your air conditioner won't stop running it may be that it has lost refrigerant so can't cool the room, so keeps running.

Does it produce cool air? If not that may be the problem and it will need repair:

find the leak and then recharge the system - that's not something that a homeowner can do.

Question: Can I Install a permanent cover for the Window A/C unit?

I want to put a hard plastic cover ( has vents on side to let air in and a lot of vents on the front to let air out) onto my window A/C unit and have the plastic painted the color of my house so that it blends in.

Is there a rule against that? - Stewart

Reply:

Stewart

I'm not sure whose rule we'd cite; I speculate that IF and I do mean IF the cover you plan to install does not change the air inflow nor outflow of the air conditioner then it'd be fine.

Watch out: If you restrict air flow around, into or out of your air conditioner, the unit will work harder, cool less, and perhaps have a reduced life.

Use our email found at CONTACT at page bottom to send me a photo of the outside of the window unit and the same unit with your cover installed and I can comment further.