Tips & Advice

Common air conditioner problems

More than 70% of Australian households have some form of air conditioning (ABS 2018). However, many homeowners don’t monitor or maintain their air conditioners. Leaving fault detection until too late. This can result in serious deterioration of the unit and impact your comfort.

Curran’s trained air conditioning professionals have put together the following checklist so you can identify any issues now and in the future.

We take you through the most common air conditioner problems below, including:

Tripped air conditioner

For power stop problems, first look in the fusebox (switchbox) to check if the air conditioner’s circuit breaker or fuse (labelled AC) has been tripped. It may happen after a thunderstorm, or if the power grid restarts after being switched off. You can reset the circuit breaker, but if tripping persists you have an ongoing problem. Blown fuses will need to be replaced.

Actions: Turn off the air conditioner and disconnect its power supply until professional repairs can be made.


Leaking water


If water leaks from the indoor unit, the underlying problem could be:

  • The condensate pump has broken down.
  • A blockage, possibly algae or fungi, is causing back-up in the condensate pipe
  • A refrigerant leak has stopped the AC running.

If water from the outdoor unit is forming puddles, the underlying problem could be:

  • a dry air filter
  • broken condensate drain/drip pans
  • a bad AC seal
  • poor quality installation.

Actions: Turn off the air conditioner and disconnect its power supply until professional repairs can be made. 


Refrigerant leak

Refrigerant is the substance that cools the air. Leaking air conditioner refrigerant is one of the more common issues, and can be quite serious. An unattended refrigerant leak has implications for your health and the environment, as well as the deterioration of the unit.

You may be able to see, hear or smell the symptoms of a refrigerant leak, for example if you:

  • See a collection of really small bubbles on the evaporator coil – caused by tiny holes in the coil that develop
  • Hear hissing or gurgling noises – caused by coolant leaking through small holes or cracks in the evaporator coils and making a noise due to the high pressure
  • Smell an odd odour, such as a sweet chloroform smell coming from your air conditioner – caused by a coolant leak. Note that some refrigerants are odourless, so an odour is not the only sign of a leak.

Actions: Turn off the air conditioner and disconnect its power supply until professional repairs can be made.

Clogged AC filter

If your AC filter isn’t cleaned regularly (every two months during peak usage periods), it accumulates dust, dirt particles and even pet hairs. This leads to overheating, poor performance, increased energy consumption and unhealthy air quality.

Short-cycling might indicate a dirty AC Filter – as would the fact that you haven’t changed the filter for years.

Actions: Turn off the air conditioner and disconnect its power supply. If your unit has a replaceable sort of air filter, you can install a new filter yourself. You could clean the old one thoroughly but it must be completely dry before re-use. For the future, instil a regular cleaning regime. Consult a professional if the problem persists. Technicians can also advise on smart ACs with controllers that indicate the filter’s status.

Compressor problems

If the unit’s compressor falters, you might notice the unit isn’t working properly, or it might stop working altogether.

Actions: Turn off the air conditioner and disconnect its power supply until professional repairs can be made.

Frozen evaporator coil

This problem can arise even in warm climates and must be resolved quickly. The freezing actually results from dirt and dust gathering around the evaporator coil and heat pump. When this stops warm air from getting through to the refrigerant, the moisture on the evaporator coil can freeze.

Signs include

  • Ice on the outdoor refrigerant line
  • Overflowing condensate pan
  • If you can open it up, the air handler has moisture or condensation on it.

Actions: Turn off the air conditioner and disconnect its power supply until professional repairs can be made.

Capacitor failure


Capacitors that start and run the AC motor can overheat from prolonged AC use in summer, frequent changes in the thermostat’s setting or power surges. Due to the risk of electric shock, professional help is essential.

Signs of a capacitor failure include a clicking noise or the AC turning on or off abruptly.

Actions: Turn off the air conditioner and disconnect its power supply until professional repairs can be made.


Faulty thermostat

The air conditioner’s thermostat can malfunction due to accumulated dust or corrosion, loose screws or wires. Thermostats can be dislodged by accident and require repositioning.

If you have noticed unusual warmth or the AC is short cycling, the thermostat could be the problem.

Similar problems can also arise from the battery needing replacement or leaving the thermostat in direct sunlight, so check that these aren’t the cause.

Actions: Turn off the air conditioner and disconnect its power supply until professional repairs can be made. As well as addressing issues like corrosion, the technician can provide information on getting a smart thermostat that is operated from your phone.

Motor failure

The fan motor pumps air through the air conditioning system and is one of the hardest working parts.

Signals of motor failure in the air conditioner include a grinding sound or buzzing sound or lots of vibration. The fan might operate erratically or not at all.

Actions: Turn off the air conditioner and disconnect its power supply until professional repairs can be made.

Fan failure


A failing fan in the outdoor unit could result from loose wiring or components. Professional intervention is needed to prevent overheating and eventual damage to the compressor. Simple obstructions could also cause fan problems, but the power must be turned off before inspection.

Signs include the outdoor unit’s fan stopping altogether or a clicking sound in the air conditioner if it is a small obstruction.

Actions: Turn off the air conditioner and disconnect its power supply until professional repairs can be made.


Bad odours


The bad news is that unpleasant odours can signal very unpleasant problems. Take notice of these smells:

Gas smell coming from AC – from Methanethiol, which can be dangerous

Fire/burning smell when turning on AC – likely from an electrical component burning inside the system

Rotten egg stench – from bird, insect or lizard getting inside the system and expiring

AC smells like mildew – from mould or mildew growth, usually within the air conditioner’s filter

Actions: Turn off the air conditioner and disconnect its power supply until professional repairs can be made.


Leaking ducts

If you have a ducted air conditioning system, you need to pay attention to the ducts periodically, so enlist professional help.

Signs that the airconditioner’s ducts have a hole include reduced or erratic performance when running. Your air quality will also be impacted if dirt and debris are being sucked into the hole.

Actions: You can inspect accessible ductwork for holes or tears, which are often located where two ducts join. Turn off the air conditioner and disconnect its power supply until professional repairs can be made.

Electrical control failure

Professional assessment of failing electrical controls is vital. Faulty electrical controls may stop your air conditioner working. They can result from the stress of frequently turning it on or off, power surges, acid build-up or even misfortunate creatures that have decided to chew the wires.

Actions: Turn off the air conditioner and disconnect its power supply until professional repairs can be made.

Airflow and vent blockages


Issues with weak airflow could be as simple as the vent being blocked by furniture moved in front of it, or as complex as a faulty blower motor.

Actions: Keeping the vent area clear and cleaning filters will help, but airflow problems could be symptoms of issues with the blower motor, refrigerants or ducts. Turn off the air conditioner and disconnect its power supply until professional repairs can be made.


Unplugged air conditioner


Always, if the unit has stopped working, make sure it is still plugged in properly. If not, this is an easy fix.


Get professional help

Air conditioners require properly qualified technicians to install, service and repair them as they are complex devices. If the initial installation is shoddy or the chosen model is poor quality, you could start out with some of the problems described.

Contact Curran today for air conditioner installations or repairs or if you want to book a clean and condition service. Our repairs come with written guarantees.

Any customer can take advantage of our current $99 service that includes a clean and condition report of air conditioning.

Customers who are on our Service Partner Plan can book their FREE bi-yearly maintenance service that includes a clean and condition report of air conditioning.

We can fix all types and models of air conditioner, including:

Prevention strategies

A trained air conditioning professional will spot the common problems, as well as others you haven’t noticed yet, so booking a regular maintenance check can be important.

Maintenance inspections include:

  • Inspecting the condenser unit
  • Cleaning off any dust or debris inside or near the unit
  • Cleaning the fan motor
  • Oiling the bearings.

Remember to monitor your air conditioner between servicing. This helps to extend the life of the unit and reduce expensive problems that consume more energy. Conduct checks more frequently if your environment is extra dusty or polluted.

Get in touch with our team today to find out more.

Same day service

We will be available when you need us.

Serving The Community For 30 Years

Serving Wollongong, Shoalhaven, Illawarra and Sutherland Shire.

Award Winning Family Owned Business

We have earned countless awards of excellence from within our industry and from highly respected consumer groups.

Rated 4.9 Stars

Rated 4.9 Stars with 350+ reviews, Curran is a name you can trust.

What Our Customers Say

Testimonials from our satisfied customers

Highly Rated


Out of 5


Overall rating of 549
1st-party reviews

Viktoria Staunton
March 25, 2024
Read More
Excellent customer service- Josh went to great lengths to assist my mum who is vision impaired. Great job Josh!!
Helen Anderson
March 21, 2024
Read More
Very impressed with the fast service! Josh and Nathan highly efficient and are both fantastic ambassadors for Curran! Thanks again, great job!
Zvoni Hodak
March 21, 2024
Read More
What a great company! Our plumbing problem was fixed in less than 24 hours by a super friendly plumber, backed up by an extraordinarily professional team of managers and admins. Based on this first experience with Curran, we didn't hesitate to sign up to their partnership plan, confident in the knowledge that we now have a reliable team of plumbers, electricians and other service technicians when we need them. Highly recommended!
Francesca Pami
March 20, 2024
Read More
Very professional service. Jake came to quote me for the job and was the plumber who eventually did my plumbing. A beautiful person who was both extremely polite and respectful as well as being very skilled and so helpful. He cleaned up after the job and made sure I was happy with everything he did. I will definitely use Curran’s for my future plumbing needs.
Tim Lukacevic
March 19, 2024
Read More
From time placed call last night to the time technician arrived was good service and kept informed. Early morning phone call to get more info and see how was the tap going under the sink . Will who attended our place very nice guy . As have had Currans plumbing in the past for jobs. Now they have more different things do in the business which is great Renewed our membership We were happy and didn't realise our tap was still covered when was installed in just over a year ago. Always hold upfront what job will cost
Elizabeth Carr
March 18, 2024
Read More
Josh was very informative and took the time to ensure I understood exactly what he was doing and what the options were. Lovely fella. Even offered to take the bins out
Julie Street-Smith
March 11, 2024
Read More
A very efficient service. Knowing what you pay upfront was great, it certainly eased my anxiety about receiving a blown out bill. The service was fantastic. Very polite, courteous and respectful of my time. No hesitation In using Curran again. Grist job. Julie S
Kevin Foreman
March 3, 2024
Read More
Super responsive, prompt and professional. Very impressed.
Caitlin Williams
February 29, 2024
Read More
Ryan was very friendly & helpful. Provided great customer service during the appointment for my quote.
February 29, 2024
Read More
Excellent service! Super helpful & informative! Allowing extra time to teach and explain each step of the works carried out. :)
Julia Blom
February 26, 2024
Read More
Very good service. The plumber was polite and gave a good explanation of what the problem was with the blocked drain. I was very suprised with the low price. He got us out of a problem so we can continue to use our sink and dishwasher.
Jennifer Fraser
February 20, 2024
Read More
Jake checked out my drainage problem and was extremely helpful in providing some solutions. He was very knowledgeable and very informative. A lovely young man who was a pleasure to talk too . Highly recommend this local family owned business
Tor W-wise
February 5, 2024
Read More
Great service. Same day. Good advice. Explains everything really well
Shaun Bradley
February 4, 2024
Read More
Billy and Sam were both friendly and supportive of the project. They managed to mitigate the problem with the drainage and completed the maintenance issue professionally. Billy installed the hot water system to my satisfaction and I was very impressed with the quality of the work and the cleanup work done. I would recommend Curran plumbing to my friends, neighbours and family. Thanks Billy and Sam for your services.
Stephanie Robinson
February 1, 2024
Read More
Really helpful, guys explained everything clearly and were very thorough.
Garry Paterson
January 31, 2024
Read More
Dylan and Jake provided great service. They were professional and respectful. Communications of the job at quote time and during the job cannot be faulted.
Sandi Sattlecker
January 29, 2024
Read More
Great, friendly, professional service. I was kept informed at every point, even receiving updated info on the Sunday of a long weekend, about my upcoming appointment. Thank you Andrew, Jake and Josh!
ForTunes Well
January 24, 2024
Read More
Great service and the young guy Isaac was very friendly and super informative.
Susan Russell
January 20, 2024
Read More
Prompt reply to initial enquiry. Date and time to suit. Wonderful customer service from trades and helpful polite and skilled. Love the service partner plan
Cherie Rien
January 17, 2024
Read More
Lovely people to talk to and so helpful. A very professional service and the tradies are all very friendly I would highly recommend Curran Plumbing to anyone who is looking for a fairly priced plumbing solution 😊
Tracey Xuereb
January 12, 2024
Read More
Great service. On time, explained everything thoroughly, very friendly and job done professionally. Highly recommend.
January 12, 2024
Read More
Prompt efficient service to our house in Jamberoo, happy to recommend.
Tertius de Vries
January 10, 2024
Read More
Professional prompt and good workmanship!
Roger Summerill
January 10, 2024
Read More
I found staff excellent and helpful they explained everything clearly
Saheel Singh
January 10, 2024
Read More
Reliable and efficient - great service 😊
Jessica Kennedy
January 9, 2024
Read More
Curran plumbing were on time every time we were booked in, the young men that came to our house were efficient and very friendly. I would recommend them to anyone.
Tony Crawford
January 8, 2024
Read More
Arrived on time, fully explained what needed to be done then quoted up front. Completed the job and cleaned up afterwards. I will be using them again for future plumbing jobs.
Tessa Jane Ryland-Parsons
December 19, 2023
Read More
Thank you Curran Plumbing. Once again excellent customer service. Prompt notification of when the technicians would arrive and honest opinion on our options.
Arvin Villano
December 10, 2023
Read More
Excellent customer service and the quality of the work done is perfect. Very professional.
Kathy Mckenzie
December 6, 2023
Read More
I have nothing but praise for the guys (Josh, Hunter & Bailey) that visited my house recently to undertake several electrical jobs and an air conditioner service. They were all very polite, professional & answered all of my questions. Also you can’t beat an interest free payment plan to help with the expense at this time of the year. Thank you
Steve Taylor
December 4, 2023
Read More
The team were on time, very professional and I was informed of all that was to be done before and during and then a summary at the end of the job. We were very impressed. Thank you also for replacing our old gas hot water system so quickly
December 4, 2023
Read More
Excellent professional service and work completed quickly and without any incidence. All work was carried out in a timely and expedient manner and workmen were very courteous
Helen Barlow
November 30, 2023
Read More
Good service by courteous efficient and helpful tradesmen!
Lee Jourdain
November 29, 2023
Read More
Curran were out within an hour of my call. I was fully advised by the person on the end of the phone of their procedures and they communicated with me by text and email during my wait. The technician gave me 25 mins notice of his arrival. He advised me what he would be doing, the price, and when he was about to turn the power off. Fixed the problem in 20 mins. I was very impressed with their customer service.
Kathryn Hughes
November 22, 2023
Read More
Same day service a bonus. On time and presented well. Explained everything well. Very happy with the service. I have used them in the past and will continue to use and recommend.
Ann Cameron
November 22, 2023
Read More
I was very pleased & impressed with the quick service & politeness of this young men & also the way they cleaned up & put everything back the way it was ,I would definitely recommend Currans Plumbing to anyone.
November 20, 2023
Read More
I have no hesitation in recommending Curran's to anyone needing repairs or installations in their homes. Top service and attention to detail; tradesmen are all polite, courteous and respectful. At every stage of the job they checked before going ahead if problems were discovered. Great work Currans!
Max Zalakos
November 18, 2023
Read More
Excellent and friendly service by experienced personnel who knew exactly what to do, and do it well, and expeditiously. Very happy!
Brendan Nolan
November 16, 2023
Read More
Shout out to the team at Curran's for the quick response and top-quality service!
Radu Bliuc
November 15, 2023
Read More
Great service from Jake and CJ. Professional, punctual, efficient, great in communications the technical aspect of the job. Well done!
Brett T
November 14, 2023
Read More
Explained the job. Professional and friendly. Great after sales service.
Onge Onge
November 9, 2023
Read More
Guys did a great job in not so easy circumstances and short notice, very polite and professional. Answered any questions I had and kept us updated all the way. No problem recommending Curran for any plumbing work.
Belinda Dakin
November 7, 2023
Read More
Levi was informative, did the job in a timely fashion and was a pleasure to have here.
HelloBeauty Home Salon
November 2, 2023
Read More
These guys never disappoint.professional, courteous and transparent.I wish more tradies used this business model.
David Smith
November 2, 2023
Read More
We had a blocked sewer. Communication with the organisation wad easy. I was kept informed about the job. Nathan was polite, well presented and had a great attitude. He explained what he would do and why. The job was done well, he explained what he did and what the result of his work was. He did a great job. Thanks
Narelle Lovell
November 2, 2023
Read More
Very professional service would recommend highly
Dianne Hosa
October 31, 2023
Read More
They were on time. They rung before coming as they said they would. They explained what they were doing before they started doing the work. They show me what they did and made sure everything was working efficiently before leaving.
Cheryl Harris
October 27, 2023
Read More
I found the guys at Curran Electrical and Plumbing to be great, they were open really friendly and helpful. They did the job on time with no mess. I also found them to be honest. I thought I had to replace two lights in the bathroom however while installing the new ones we found another switch so I did not need them replaced after all and the quote was adjusted to reflect this.
Bryan Rugg
October 25, 2023
Read More
I found the work that was completed was to an excellent quality. The workers were professional in their responses to questions and they were always on time.
Paul Blanden
October 25, 2023
Read More
Excellent work from Josh & Hunter. Very professional, polite & great work. Greatly appreciated. Thank you
Jimmy's Burger Truck
October 23, 2023
Read More
very professional service and friendly, knowledgeable staff. tidy workers that kept the business clean as they were working throughout the job. highly recommend !
October 18, 2023
Read More
Very efficient and friendly service. I highly recommend these guys.
Jennifer Bean
October 16, 2023
Read More
The contractors (both electrical and plumbing tradespeople) were personable and professional. It was great service, they arrived on time, checked each decision with me and worked hard. They were clean and tidy and treated my place respectfully.
Kevin Ryan
October 15, 2023
Read More
Quick service and helpful staff both on the phone speaking to office staff and the young plumber who came to do the job
Michael C
October 10, 2023
Read More
They assessed the job clearly, told us what was needed, and explained how they would work. They turned up on time, were polite, and did the work with a minimum of fuss.
Charlie Bell
October 6, 2023
Read More
Curran were able to come to me at short notice after a sewer disaster. They kept me informed of timing and Jake the plumber was clearly knowledgeable and passionate about his trade. He was efficient, thorough and happy to answer questions and tell me why and what he was doing offering a practical solution to our ageing property’s plumbing needs. Thank you. I’ll be in touch
Tracy Webb
October 5, 2023
Read More
Fast and efficient service with everything explained before the job was commenced. Professional and friendly which was very nice.
Jono Q
October 3, 2023
Read More
Very helpful people, happy to talk through what they were doing and why.
Katrina Toland
September 25, 2023
Read More
We use Curran's for any plumbing requirement we have. They communicate well and are conscious of the importance of everyone's time. I totally recommend their services.
Mitch Ashford
September 12, 2023
Read More
My mother who's in her 80's needed her toilet fixed. Curran Plumbing and Electrical did everything perfectly. Service was fast, plumber did a great job after informing me of the several options I had. He was also polite, well mannered and friendly, taking the time to ensure I understood everything he did. Service was perfect and I highly recommend Curran Plumbing and Electrical
Merryn Wright
September 12, 2023
Read More
Curran Plumbing & Electrical recently installed a new pump on my rainwater tank. I am very pleased with their work and also that they were able to do it within a few days of getting their quote. I also appreciated that when the quote was done that a video was taken of what needed to be done, so that whoever did the work knew what needed to be done.
August 26, 2023
Read More
Had a new toilet installed and 6 taps replaced with ‘quarter turn’ taps to aid my arthritic fingers. Perfectly happy with the work and the very professional and friendly tradesmen. Gold stars to Luke, Josh and Jake
Jeff B
July 01, 2023
Read More
Jake arrived on time, we talked thru our issue and he checked out our storm water problem. He was easily able to pinpoint our blockage and put together 2 quote options to rectify the fault. Jake is a good representative for the business👍
John Q
June 29, 2023
Read More
Well done team. Great to finally meet a professional company. You guys responded quickly, found the problem, gave a respectable quote (unheard-of nowadays) and got the job done. This is the place to go if you have any electrical or plumbing needs. Thanks again Curran
Kelly S
June 28, 2023
Read More
Sam was excellent. He was on time, polite, and did a fantastic and thorough job. He gave us detailed options for the job and we appreciated his honest and professional opinion. We will 100% use Curran plumbing again.
Dave P
June 04, 2023
Read More
Sam was bang on time and fixed our septic issue very quickly. He also sent a camera up the pipes to ensure everything else was fine before leaving. We've enjoyed our ongoing relationship with Curran after they did some major works for us last year and our membership is well worth it.
John D
May 26, 2023
Read More
The people doing the work were friendly, professional and informative and the work was carried out in a timely manner. You should be proud of the plumbing and electrical people who completed this work
Gordon M
July 18, 2022
Read More
Currans supplied us with constant updating of the project and when completed arranged for an inspection of the completed works.
Mitchell F
July 16, 2022
Read More
From the first phone call Curran plumbing services were professional, showed up on time for scheduled quote , then me updated when the job was going to be completed . On the day of install all of the staff were well trained , well spoken and installed my new instantaneous gas hot water system like they were installing it in their own home . The quality in detail to make sure I was satisfied didn’t go unnoticed. At the end of the day I feel like I have gained a plumber for life . 100% recommend.
InJect A Joint V
July 13, 2022
Read More
Luke was a Complete Gentleman and he explained every detail to my wife and i!! On this basis we excepted his Quote on the Spot and told him to go ahead and install our Brand New Australian made Hot Water System!! It was all Done that afternoon with Expert Precision d we had Hot water by 4pm!! Absolutely Marvellous Well Done! Sid you should be Very Proud of the Workmanship that Luke Performed!!
Brian D
July 13, 2022
Read More
From my first contact with your company to completion of the job was only a few days tree roots in the sewer pipes gone, big thanks to your team.
David Collins
July 11, 2022
Read More
Hi it's Dave from Dapto for Block drain problem, Part of Sewer drain renewal and ground was leveled nice & looks good, kitchen drain came apart and was reconnected all services where friendly and good communication excellent work. Thank you
Kingfisher Maritime
July 10, 2022
Read More
I found Josh from Curren Plumbing to be very honest and trustworthy in the work he carried out at my home. Josh communicated everything he was going to do and the results of these actions in a manner I was able to understand. I was happy with the work Josh did at my home.

Plumbing, Electrical, Heating & Air

Wollongong, Shoalhaven, Illawarra and Sutherland Shire

Google review mob

Subscribe to our newsletter

Get valuable trade secrets, handy tips & advice from our expert tradespeople, and exclusive offers delivered straight to your inbox.