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Q: I’ve just turned on the air conditioner for the summer but have yet to get comfortable. The appliance circulates air, but nothing refreshingly chill. My air conditioner is not cooling at all. How do I fix it?
A : It ’s the last affair you want on a sweltering summertime ’s 24-hour interval : a central airwave conditioner not blowing cold-blooded air . While your first response to melodic line conditioner trouble may be to contact an HVAC professional , with a little ofyour own AC troubleshooting , you might be able to remedy the problem and spare on a costly house call .
atmosphere conditioning systems control on a basic scientific process call phase angle conversion .
There are several possible causes of an AC system that is blowing warm air . The following are a few thing to check when your air conditioner is not cool down your blank .
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Check and reset the thermostat.
It may seem dim-witted , but sometimes when an air conditioner is running but not cooling , it is only the result of someone switching ahome thermostatfrom “ Automatic ” to “ Fan . ”
When the switch is arrange to “ reflex , ” the thermostat switches on the atmosphere conditioning when the indoor temperature arise above the desired preset temperature . If the switch was accidentally set to “ Fan , ” the unit will foul up melody through the canal system , but no cooling will take place .
promiscuous DIY fix : This is the easiest agency of fixing an AC organization : Check and reset the switch from “ Fan ” to “ Automatic . ”
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Replace the dirty filter.
If it ’s been more than a couple of months since you’vereplaced the issue - air filtersin your AC system , they may be choke and muddied , and may be affecting air flow . When filter get constipate with animal fur and dust , the AC system ca n’t draw in sufficient tune , and as a answer , only a wimpy flow of melody come out .
“ A dirty or clotted aura filter is one of the most usual reasons why your strain conditioning social unit is n’t working at maximum efficiency , since it will restrict right , clean flow of air , ” says Syed Shahzer , engineering applications and training manager atBosch Home Comfort .
gentle DIY fix : Remove and inspect the issue - air filter . If you ca n’t see what ’s on the other side , either strip it ( if it ’s washable ) or replace it . Shahzer read , “ You should be either cleaning or replacing your air filter at least once every 3 month — or every 2 calendar month if you have indoor pets . ”
Photo: Tom Fenenga for Bob Vila
If you may see through the filter , the problem with your AC not cooling Trygve Lie elsewhere .
Clear the clogged condensation drain.
airwave conditioners work in part by take away humidity from the air ( through condensate ) , and that wet must go somewhere . The job of a condensation drain hose is to lead that moisture to a floor drainpipe or to the outside of your home , depending on your system . abridgement drains are dependent to occlusion by mold and algae increase . When this happen , some air conditioner wo n’t vaunt insensate melodic line , while others will shut down whole .
well-situated DIY localisation : situate the end of the condensation drain crinkle ( it ’s often in a public utility company room ) and visually visit it for clogs . If you see a clog , cautiously clear it out with the conclusion of a small screwdriver or interchangeable narrow-minded item .
If a clog dancing form higher in the pipeline where you ca n’t strive it , put on suction to the end of the line will usually remove it . Use the hosepipe on awet / dry workshop vacuum — and control your hands around the opening — to produce sufficient suction between the two hosiery .
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After removing a mold or algae geta , pour a couple of cup of blank acetum into the abridgement goat god that lies beneath the evaporator coils in the inner blower social unit ( memorise how to get at and identify the coils and the condensation pan below ) . The vinegar will kill residual mold buildup and reduce the risk of succeeding clogs .
Try to diagnose duct malfunctions.
In a central AC organization , the primary cetacean mammal forces cold air through the ducting and from there into case-by-case rooms . If a duct somewhere between the blower and a way registry ( the grille that covers the possibility of an HVAC duct ) has fall apart , the cold melodic phrase could be blowing out before it reaches the room ’s register . If cool air is bollix up from some registers but not from others , there ’s a good probability the ducting that feeds the registers is at fault .
Easy DIY location : If you have an unfinished cellar , you could try the ductwork to see if a junction has come loose . If so , refit the ends of the joint and tape the young joint securely with canal tape . If a ducting joint has come at large within a ruined paries , however , you wo n’t be able to easily place it and it ’s best to call an HVAC professional .
Clear the area around the compressor.
If dry leaves and debris have mob up next to the compressor unit , it may not be capable to run in sufficient strain . To detect out , locate the compressor building block , which will typically be tucked off on the back or the side of the house , where it wo n’t draw attention .
Easy DIY fix : Clean away all rubble or anything else that might be crowding the unit , such as weeds or overgrown vines . To ensurepeak performance of your line conditioner , do n’t aim anything on top of the compressor .
Clean dirty coils.
If your line conditioner is make for but not cooling , marked-up coils may be the culprit . The distinctive AC organization has two sets of gyre : condenser coils , which are located in the outdoor compressor building block , and evaporator coils , which are encased near the indoor blower unit of measurement . When either set of coils becomes ill-gotten or covered with mold and junk , frigid air output can suffer . strip the AC coilsinvolves removing the alloy enclosures that protect them .
well-situated DIY fix : If you do n’t feel comfy open up the AC units you may rent a pro to clean them . If you ’d wish to try on clean the coils on your own , however , take these steps :
Tried-and-True Advice
“ One summer , my AC was n’t cooling , and I assumed it was low on refrigerant . Before forebode a technician , I off the front panel and found a mental block of ice inside the evaporator coils , despite the red-hot atmospheric condition . The perpetrator ? A clogged air filter restricting airflow . A wide-eyed filter replacement and letting the ice amply melt down ( by running just the fan for a few hours ) got my AC working again . If your AC stops cooling , check for Methedrine before assume a major issue . ”
Buy a more powerful air conditioner.
If you ’ve recently added on to your survive space or purchased a novel cooling social unit and the AC is not reaching the want temperature , then the unit of measurement may not be sized right for the space . “ If your unit is running long cooling cycles and/or is not able to efficaciously cool your infinite when it should , then your unit may be too pocket-size , ” says Shahzer . “ You may also notice a lot of humidity and sticky airwave . ”
A ecumenical rule is that 1 gross ton of cooling ( 12,000 BTUs ) is want for every 400 solid feet of space . But that ’s a general rule , and term depend on the climate , window , the identification number of citizenry in the outer space , and other life-style factors . Jeff Ault , practical HVAC expert with home inspection and repair companyFrontdoor , explains : “ Less than ideal humidity and temperature are factor affecting the AC performance , and if the humidity and temperature never seem to attain the hope puff level , the system may not be sized correctly . ” He sum , “ observe that your HVAC declarer ( or a Frontdoor expert ) can access software that takes in data point and a home ’s factors to calculate the proper sizing . ”
Fix a blown fuse or tripped circuit breaker.
A blown fuse or tripped circuit ledgeman is unremarkably a symptom of a larger problem since it ’s there to protect the electrical organisation when the motor fails . If the circuit is jaunt and you ’ve gone through all of the other fixes above , you may involve to contact a professional person to look into the take .
“ A blown electrical fuse or tripped breakers is a symptom of a trouble . An HVAC technician would be needed to determine why this situation occurred and how to address it so the home system is function properly , ” says Ault .
Add refrigerant.
If the air conditioner is not blowing cold-blooded air but run and you ’ve try all of the method above to increase its yield , your AC unit may just be scurvy on refrigerant . Unlike the other muddle above , this is n’t a distinctive DIY line . It requires refuge gear wheel , and getting it wrong may mean having to replace the AC whole altogether . It ’s also a line of work that should n’t be put off .
“ This can also promptly lead to more expensive energy bills since your unit is working extra time to by rights cool your nursing home but lacking the basic material , ” Shahzer says . In accession , it can conduct to other issue .
“ When the system is totally out of refrigerating , modern units will trigger an ‘ LPS ’ ( low - pressure level electrical switch ) that will shut the building block off to protect the compressor . you’re able to tell this is happening when there is aviation come out of the vent , but it will not be cold , and the outdoor unit will not be endure , ” says Ault of Frontdoor .
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Know when it’s time to call an HVAC pro.
If you ’ve gone through the DIY steps above and yourAC systemis still not cooling , the job could be leak out refrigerant or a failed compressor unit . As we ’ve said , refrigerant are federally regulated and may only be handled by a licensed HVAC professional — you could n’t replace them yourself if you want to . At this stop , it ’s time to call a pro .
If the issue is an AC unit not blowing cold aura and your AC system of rules is more than 10 year old , you may have a failed compressor and might need to purchase a new organisation . Again , this is an proceeds that can only be diagnosed by the pro , so make the call .
Final Thoughts
When an AC building block is not be adrift cold air , there are many possible cause that can well be fixed without the help of a professional . From change the filter to checking the thermostat background to clean the coil , there is much that you may do to get your airwave conditioner working again quick and keep your home nerveless . “ The best affair a householder can do is to keep their system unclouded with unconstipated filter change , rinse off the coils on outside units , and cleaning out the drain product line with a store vac , ” says Ault .
However , if you ’ve tried all of the air conditioner troubleshooting and DIY mend and your AC is still not working , it ’s meter to call a pro for an evaluation . And remember these wise word from Shahzer : “ Always keep an eye out for warning sign . Things like eldritch noises , bad smells , fond tune and/or humidity , and lots of condensation are not normal , so do n’t push aside them . ”
If the professional enounce it ’s time for a raw AC , be certain to search his or her passport in ourguide to the best air conditioner brands .
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FAQs
Turning off the AC is usually helpful and sometimes required to safely investigate some of the possible issues with an AC system not cool . If the thermoregulator background is the issue , it ’s not necessary to turn off the AC .
If the air conditioner is blowing cold air travel but not cooling the menage , the rest home could be leaking air to the outside . Check that all windows and doors are close . If the melodic phrase feels cool than the room temperature but is not as nerveless as desired , this could just be thefan blowing .
If the blowing air is warm or if you get a line loud noises or vibrations when begin the air conditioner , then the compressor may be going bad .
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release off the mightiness to the air conditioner at the breaker board , press the reset clitoris on the unit for a few seconds , and then turn the whole back on . Check the drug user ’s manual of arms for your particular building block for specific instructions .
Most expert recommend waiting about 30 minutes after pushing the reset button before turning the unit back on .
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