This is why Split-Type air conditioner units begin leaking | AIRCARE SOLUTIONS

This is why Split-Type air conditioner units begin leaking

When a split-type air conditoning unit begins leaking, 99% of the time it's the result of a blocked drainage line. Besides the cooling function, an air conditioning system is also very effective at removing moisture from the air to provide a comfortable environment. The moisture collected must go somewhere, it does not simply disappear. As the HVAC system removes moisture from the air, it collects as condensation on the evaporator coil that then drips into the drain pan. The liquid then travels through the condensate drain pipe to connect with the main plumbing to be dispelled. The condensation created by the system can be filled with dust particles as well as bacteria, and this leads to a build up of algae in the drain pan as well as within the drainage line. 

The most common air-conditioning systems utilized in residences are Split-Type air conditioners and Window-Type air conditioners (also referred to as Box Units). Both of these AC systems rely on gravity for dispelling of the condensate from the drain pan through the drainage line. The drainage line for Window-Type units tends to become blocked less frequently, as more often than not, the drainage line is connected vertically to the drain pan which results in the condensate flowing rapidly through the drainage line. Contrast this to Split-Type AC's where the drainage line often travels a significant horizontal distance before it connects with the main plumbing - thus the condensate travels very slowly through the drainage line, and condensate pools within the drainage line when the air conditioner is not operating. This inevitably leads to a build up of algae over time, which ultimately results in the drainage line becoming blocked, and the air conditioner will begin to leak as the condensate can no longer be dispelled. AirCare Solutions personnel flush drainage lines with several litres of water under high pressure for each and every AC that we clean as a standard operating procedire in our deep cleaning service. 



In order to avoid clogged drainage lines, we recommend that air conditioner drainage lines are flushed twice per year - and at the very least, at the end of the summer season when your AC's are no longer in use. It's important to note that when algae is left within drainage lines over the cooler months when AC's are not in use, that the algae will dry and harden and solidify. Over time, layer upon layer of solidified algae will constrict the drainage line and thus the consequence is more frequent occurences of blockage. Constricted drainage lines are akin to the arteries of a person with a diet high in cholesterol - eventually it's going to present a serious problem! Once the drainage line has become severly constricted by several layers of solidified algae, simply flushing the drainage line with water under high pressure is not enough to remove all of the debris. At this point, the only effective method to clear the solidified algae is with a chemical flushing (a similar process to clearing blocked plumbing in a kitchen or bathroom sink). 


How AC's and their drainage lines are installed can have a significant impact on the frequency that the drainage lines become blocked. If you discover that one or more of your AC's are frequently leaking as a result of blocked drainage, then this is typically the result of one or more installation issues; 

(i) It is commonplace for Air Conditioning Systems to have been poorly installed which can lead to higher frequency of blocked drainage. For example, we often come across drainage lines that have a positive incline at some point along the drainage line (often immediately after the connection point to the drain pan). This leads to far more rapid development of algae within the drainage line, and often within the drain pan itself.

(ii) It is commonplace for Split-Type Air Conditioning Systems to have been poorly installed. Split-Type AC’s are supposed to be installed at a slight 1-degree to 2-degree negative incline towards the side of the AC where the drainage line has been attached to the drain pan. We often find that Split-Type AC’s have been installed completely level – this leads to pooling of water within the drain pan which in turns leads to more rapid development of algae both within the drain pan as well as within the drainage line.

(iii) It is commonplace for Air Conditioning Systems to have been poorly installed with multiple AC drainage lines converging into a single drainage line before exiting to the main plumbing of the building. These kinds of installations present a whole host of problematic issues that inevitably result in frequent drainage line blockages. The worst-case scenario is when the single drainage line, that multiple AC drainage lines have converged into, becomes blocked in which case multiple AC’s may begin leaking simultaneously. This type of installation can even result in one or more AC’s leaking when they aren’t even in operation. It is common to find these kinds of poor drainage line installations in various residential developments throughout Hong Kong. In apartment layouts where there are a number of bedrooms connected via a corridoor from the living/dining room, it is commonplace to find that there is a false ceiling running the full length of the corridoor, and all of the AC drainage lines will converge into a single drainage line hidden within that false ceiling area.  

(iv) Regardless of how well an AC and its drainage line has been installed, owing to the very nature of the composition of condensate running through a drainage line, it is unavoidable that algae will develop over time within any given drainage line. Any algae that is left within a drainage line for long periods of time (for example during the cooler months when an AC is not being utilized) will harden and constrict the drainage line. The long-term result of inadequate maintenance of AC drainage lines is that drainage lines will eventually become so constricted (or entirely blocked) by hardened algae and/or other debris and the condensate is no longer able to drain freely.

Drainage line that has become almost entirely constricted by layer upon layer of solidified algae over time

Drainage lines that have become constricted by hardened algae over long periods of time may have appeared to have had no significant issues for several years - but once the drainage line reaches a similar condition to the above image, blockages will occur far more frequently. The above image is a perfect example of why it is so important to ensure that your AC's and their drainage lines are cleaned and flushed twice per year, and most definitely at the end of the summer season. 

Here's a short clip of a dirty AC with a blocked drainage line:


If one or more of your AC's are suffering from persistent dripping issues, then it would be wise to arrange for AirCare Solutions personnel to conduct an inspection of the problematic AC(s) to identify any installation issues of the AC and/or the drainage lines. After the inspection, our personnel can then advise cost-effective recommended solutions (there's often more than one way to resolve installation issues) and provide you with a quotation for the recommend course of action. 

For a significant proportion of cases of where drainage line blockages have been occuring more frequently than would be considered within a normal timeframe, it's typically best to arrange for a chemical flushing of the drainage line to ensure that the problematic drainage line is entirely cleared of calcified algae and any other debris - and whilst our personnel are there, they can also conduct a thorough inspection of the drainage line installation to identify any defects and provide recommended solutions.

Bookings for chemical flushing are charged at $1,200 for one AC drainage line, and $400 for each additional AC drainage line. Should chemical flushing of a drainage line be required whilst our personnel are already attending to your AC's for a standard deep cleaning booking, the fee is $400 per instance. Please note that for shared drainage line installations, all of the AC's that share the single drainage line must be dismantled in order to ensure that the process is successful, as well as to ensure the protection of delicate electronic components.

If it's a real emergency and you're unable to get a booking with us within a day or two to resolve a blocked drainage line issue, then you may wish to try to resolve the issue yourself after watching the brief instructional video below. For the vast majority of Daikin ACs, it's a relatively simple process just like the video - but it should be noted that with most other brands of AC, it's typically more challenging....and with some brands of AC, just downright cumbersome! If you're in doubt, it's obviously best to wait a short while to have one of our professional HVAC technicians take care of it for you. 


Depending upon which brand and which model of Split-Type Air Conditioning system you have, it can be a relatively simple process to unblock the drainage line - which is the most common cause of a split-type AC system to start dripping. Daikin ACs are particularly well designed, and the vast majority of their ACs have been engineered with ease of dismantling and ease of deep cleaning as priority features.

So if you've got a split-type AC that has a blocked drainage line and you're handy with a screwdriver - you may want to try unblocking the drainage line for yourself if you're struggling to get an emergency booking with a professional HVAC technician.

Please note: This is an impromptu video where we had invited the client to film the process after he had expressed an interest to learn how he could unblock a drainage line by himself. So it was filmed on the fly with no preparation, no script, and in a single shot with no other camera angles apart from a brief close-up of the algae that had caused the blockage. At a later date we will be preparing a more professional video with greater detail, better/closer camera angles for the various steps in the process, as well as demonstrating the process with a few other AC brands as well. Disclaimer: ACs are electrical devices, so be sure to isolate the power by turning the AC off at the Circuit Breaker in the Main Fuse Box of your home. Simply turning it off with the remote control does not completely isolate the power.

It should also be noted that AirCare Solutions personnel will utilize a pressure washer to flush drainage lines out - not simply the pressure from one's lungs. This clip was prepared purely to demonstrate that it can be a relatively straightforward task to unblock a split-type AC condensate drainage line with just a screwdriver and a short length of standard garden hose. Lastly, it should be noted that drainage pans, condensate, and condensate pipes, can contain significant levels of bacteria - so one should take care not to ingest any condensate if using ones lungs to force air pressure through a drainage line.


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Lee Johnson

I had read some very enthusiastic reviews which almost seemed too good to be true but nothing was overstated, everyone was very responsive during every step of the booking and the servicing was efficient and extremely helpful and they really go the extra mile. I also love how they use super effective plant based cleaning products. I highly recommend this company.

Stephanie Ip

Really professional service. Was given a quote beforehand with transparent pricing. No hidden costs. Couldn’t believe how clean the AC units were after the team left! Highly recommend AirCare Solutions and will be booking them on a regular basis to keep my AC units in tip top condition!

Evelyn Kang

We are home owners and the AC in our living room had been a nightmare for us for 5 years. We've had multiple contractors come to unblock the drainage line, often several times per year, and none if them were able to resolve the issue. One company even quoted us $30,000 to fix the problems! Then we contacted AirCare Solutions after hearing so many good things about them from a good friend. During their visit to clean all of our ACs, they took the time to investigate the shared drainage line installation within our false ceiling, and very clearly explained to us the multiple issues that had been plaguing us. Everything they explained made complete sense, as opposed to the strange explanations that other contractors had made previously.Our drainage lines had been poorly installed, causing frequent buildup of algae which was clogging the drainage, resulting in our living room AC being unusable most of the time. AirCare Solutions adjusted the drainage line at the cleaning appointment to fix an obvious inclination issue, and then we booked them for technical services to come back and conduct a chemical flushing to remove all the calcified algae, as well as to install a condensate pump to fix another issue for which we would otherwise have had to break open a concrete wall to enlarge the conduit. Now that there's no more pooling of condensate in the drainage pan of our AC, as well as no pooling of water in the drainage line, we can finally use our living room AC again. Such a relief to have finally gotten clarity on what had been causing the issues, and so happy for their solutions! One very happy customer ????

Julie Petris

I had recently heard of AirCare Solutions and thought that I would give them a try. They did a fantastic job on all 4 of our split AC's - one of which is very old and delicate, and as we have very high ceilings the other 3 are not easy to access. My helper and I were amazed to see how much mold and grime came out of them - very glad that we had them done before the summer. Thanks guys!

Lotta George

Air Care Solutions were great! Arranged for them to come to check our air cons which had recently been cleaned by someone else. They were punctual and very professional and thorough. They really did a great job! Highly recommend !

Zdravka Paskaleva-Newman

Shout out to AirCare Solutions who did a fabulous job on our AC's today! They're all incredibly clean, the crew was thorough and very professional. Even took videos before and after for my reference, and they even managed to resolve an annoyingly noisy fan barrel issue for us - now my kids will be able to sleep better at night. Thanks guys!

Rebecca Hardman

I had a positive experience with this company from first contact until the job was completed. Communication was swift, knowledgeable and professional. They brought all the right equipment and completed the tasks in a timely and efficient manner. My ACs are now clean and running more smoothly. I would use this company’s services again and recommend them to others. It was also beneficial to be able to communicate in English as I don’t speak Cantonese. Thanks for your brilliant services and help! Much appreciated.

Tanya Hart

Hi! I just got my air cons cleaned by a fab crew. Good communication, no up-sell, in fact when they noticed two were new & not grimy, they just removed from quote without being asked. Didn’t mess up the house. Sent me before & after pics. Window type aircons are quieter now. Very happy.

Jason Prohaska

We're moving into a new flat and they actually rearranged their schedule to come clean before we moved in. Got a detailed report to show the landlord and they said the landlord could contact them directly if there was any questions (removes me from the equation...THANK YOU). Showed me before and after videos as proof of their work too. Messaged me to say they were done and would be sending me a revised quote. I just assumed it would be higher. I was shocked to see it actually was lower than what they previously told me. All in all, so impressed with their work, price and integrity. If you want to get rid of the nasties in your AC's, I would highly recommend these guys.

Sally Humphries

Excellent service from start to finish. Extremely professional, timely and thorough. Was given the low down on every aspect of the process including detailed videos of before and after cleaning which were shocking! The AC works so much better now. The company is English-speaking run by expats, which helps. The booking process was very easy. I’ve already recommended it to others who were equally satisfied. Would highly recommend without hesitation.

Ronney Ngan

Professional service and genuine willingness to help and to share

Cheryl Lai

We had our air conditioner units cleaned by the team recently. Service was great, they were extremely thorough and they also provided me clips of each unit plus a report at the end which I can share with our landlord. I would not hesitate in recommending them.

Phillip Wu

Great service. On time and follow through all issues. They are professional and great help and service. Definitely will hire them again.

Jeanny Kim

Highly recommend AirCare Solutions! We had our air conditioners cleaned yesterday and they were extremely thorough, professional and friendly. We will definitely be getting our air conditioners cleaned regularly.

Nathan Keltner

I used AirCare Solutions too and was super pleased. I’ll easily use them next time as well.

Tracey Godfrey

Fantastic service. These guys really know their business. Efficient, knowledgeable and friendly. We’ve had several other AC companies in the past, none of them have been anywhere near as good as this company. Highly recommend

Sylvana Lee

They came the same afternoon that I booked and were kind, informative, clean and tidy and above all did a fab job. Would highly recommend and will be using them for any AC maintenance I have

Isabel Bermudez

AirCare Solutions was amazing! The level of detail and communication was wonderful. We have a 4 month old baby, so it was really important to us that the AC be cleaned. Not only did they send us videos of before and after, they double checked everything before they left. There was no mess or strong chemical odour either. We’ll be cleaning our units with them from now on.

Laura Kelly

Just had a cleaning of two units with AirCare Solutions and it was a pleasure. They arrived on time, personable and friendly service, and after cleaning gave some really good tips about further use which was really useful. I’ve never had anyone clean up so well after. When the cleaning was finished, the AC's were working good as new. I had to leave the house and when I came home the remote control wouldn’t work so I messaged them directly and they still responded at 10pm! They came the next day with no fuss, no charge, and they resolved an issue with the sensor. Really great service and would absolutely recommend.

Joanne McKee

I have just used AirCare Solutions to deep clean our leaking air cons. They provided a great service. Fast response, thorough clean, careful with furniture, using protective sheets. The AC’s are now spotless and icy cold

Hazelle Andrea Antonio Velasquez-Tse

We just had all of our aircons professionally deep cleaned by AirCare Solutions - we hadn't had our AC’s cleaned for a long time and we noticed that the AC’s weren’t cooling very well, and two of them were leaking. We thought that they needed repairs, but AirCare Solutions advised us that they likely just needed a deep clean and for the drainage to be cleared. They were right - after cleaning, they work like new, and no more leaking. They even unblocked our sink for us while they were here!

Sabrina Ann Chan

Highly recommended, very professional and excellent customer service!

Paloma Gerber

We just had a cleaning done by AirCare Solutions Hong Kong, and were very impressed by their customer service. A good cleaning job and value for money, but above all, they excel in customer service. They were always highly responsive and went out of their way to make sure we were more than satisfied. I highly recommend their services!

Cheryl Lai

We used AirCare Solutions to clean our air conditioners recently and I must say, they were fantastic to deal with. I have found it difficult to find available technicians at this time of year so I was pleasantly surprised when they were able to organize our clean at very short notice. The gentleman that came was on time, extremely helpful and our units are now running well again. They even sent us a report afterwards which detailed an installation issue that we were then able to share with the owner. We will definitely be using them again and would highly recommend them to anyone here.

Isabel Bermudez

They are awesome! Our apartment has been so refreshing to be in :o) We even messaged them to ask an air con related question weeks after their visit, and they still took the time to answer!

Min Chen

We just used AirCare Solutions to clean our AC and we also had a similar excellent experience! I would also recommend them, and our AC is working much better after the clean.

Catherine Hwa-Schelander

They have just cleaned 6 units for us as well and did a fantastic job - really thorough and they even made videos to show us the before and after results of the cleaning. Great communication, great cleaning and overall great service - the best we have had in the 7 years we have been here in hk. Highly recommend!

Vn Leung

We just had three of our aircons professionally cleaned by the Aircare Solutions team, and they were really friendly, on time, reliable and professional. Our aircons are now smelling fresh, are cooler than before, and we are very happy. Not only that but they made sure that all our furniture/items were put back exactly as they were and cleaned up every trace that they were even here, this no-mess no-fuss service is well worth it. Now the only problem is that next Summer when we get the service again, we’re afraid they’ll be fully booked since everyone is so happy with them

Fiona Lee

I hired these guys after seeing all the fantastic reviews here and am glad to report that they did not disappoint. 5 star service, great communication, knew what they were doing and just really nice guys overall. Our air-cons were disgusting but looked amazing after they were done with them, will be recommending these guys to anyone who needs their air-cons cleaned!

Vn Leung

Hi all, I just wanted to recommend AirCare Solutions A/C cleaning company, they cleaned three of our air conditioners recently and we had a really pleasant experience. Though it’s been a rainy week, it’s still going to be a hot couple of months ahead so I thought this may be useful for the group – especially when many of us are working from home because of COVID-19. They use nontoxic, eco-friendly, 100% biodegradable products, safe for kids & pets, very professional, excellent communication, punctual. And on top of that, NO LONG WAIT! I booked with them and they came within a week. You just need to give them two booking preference times. My aircons had this musty smell before but now that’s gone, and the air is much cooler than before and I don’t feel like I’m inhaling gross stuff anymore. Highly recommended

Claudia Primavera

Thanks for recommending! i just had cleaning done by Aircare Solutions and couldn't recommend them enough, very happy with their services!! They really went above and beyond with the massively thorough cleaning, very great attention to detail and even helped clean my shower free of charge which is defo very rare here!! The team's super responsive as well, I booked mine just last week and it was sorted quickly. All in all, really highly recommend the business!

Sarah Hamilton

We just had our air con units serviced with AirCare Solutions. Very pleased with their service - they managed to squeeze me in on the day I called as I had a leak and they even managed to fix it (two previous companies were unable to fix the leak!). Highly recommend them!

Stephen Gavin

AirCare Solutions provide a professional, personalised experience, and go above and beyond to provide a thorough clean. My aircons feel brand new! The whole experience from booking to completion was smooth and hassle free. I was referred to AirCare Solutions by word of mouth from a friend, and I will continue to spread the word!

Jade Poon

I had a GREAT experience with AirCare Solutions today! I had an aircon that was dripping in my baby's room so needed it fixed ASAP. Scott and Max squeezed me in today and unblocked the drain and gave it a thorough clean. They also cleaned all my aircons and took before and after videos. They were extremely friendly and professional, gave us tips on how to care and clean our aircons. Even my helper found them very helpful and nice too. I've had lots of aircon cleaners/ fixers in the past and this was by far the best experience ever!

Ilona Magyar-Bakó

I just had my aircons cleaned with AirCare Solutions after I saw this recommendations and couldn't be happier. Very easy booking, super quick response from the customer service and no long wait for the actual cleaning (they were able to come in the time slot I requested which was within days of the booking). The guys were super nice, they really took their time to do a thorough job (took before and after videos of the inside of the aircons) and cleaned up beautifully after themselves (although they didn't really make a mess). All in all, we couldn't be happier with their service, highly recommend them.

Andrea Charity Battad Cristobal

We loved AirCare Solutions ! Super friendly with my curious kid and honest about the cost of fixing one of our old aircons vs. buying a new one. Wonderful to have the before and after videos as well!

Youssef Ajdir

Very professional and efficient. I couldn't be more happy with the quality of the service and the way they handled my issues from the booking process up to their followup

Harriet Rhodes

Very professional and knowledgeable. Would definitely recommend and will use them in the future!

Mamta Mukherjee

Thank you for doing an amazing job! At such a short notice, you not only serviced the aircons and cleared the blockages but did it with so much care and patience! Loving the clean air. Thank you!

Rahat Jabeen

Punctual & cheerful staff, excellent communication about any aircon issues & possible solutions, left everything clean and tidy. Overall best aircon service I've used so far in Hong Kong and we'll definitely be using them again!

Susanna Heinonen

What can be said about the 5-star service? Communication has been 11/10, cleaning itself was 11/10 and the staff themselves I will rate 20/10 - they explained everything, offered solutions and from the point of view what's best for me, not for their wallets! Will use AirCare Solutions from now on, so pleased with the service that I can't recommend them highly enough!

Martin Raynier

Highly recommend AirCare Solutions Hong Kong. Very Professional and Efficient !