Do-it-yourself split system repair: main breakdowns and ways to fix them

Split systems are becoming more and more popular every year.With their help, you can maintain optimal air temperature in rooms of various sizes and purposes. They have an affordable price, and a set of useful functions allows them to be used not only in summer, but also in winter, as an additional heating device.

Such equipment rarely breaks down. In most cases, it can last much longer than the warranty period. But, in case of improper use and maintenance, breakdowns are inevitable. In some cases, you can repair the split system yourself without using specific tools.

But how to detect the cause of the malfunction and eliminate the breakdown? We will talk about this in our article. We will also consider more rare malfunctions and prevention methods.

Main equipment components

You won’t be able to repair climate control equipment yourself without knowing all of its elements.

We suggest you understand what a split system consists of:

• compressor-condensing unit (outer);
• evaporator unit (indoor unit).

Each block contains certain parts. The external parts of the equipment include: compressor, condenser, four-way valve, control board, fan, filter, housing.

The internal part of the equipment is installed indoors. A consists indoor unit from: front panel, filters (coarse and fine), evaporator, display panel, fan, condensate tray, control board.

There are a lot of electronics in air conditioners. It makes it possible to control the temperature regulation process. The boards consist of several dozen electronic components, which are also sensitive to contamination

The equipment also has a copper tube system. The refrigerant, freon, moves through them. During operation of the equipment, it is in two states: gaseous and liquid. Therefore, the tubes differ in diameter.

Diagnosis of faults in the split system

Before you start repairing the split system, you need to roughly understand where to look for the problem. For this purpose, there are error codes that are displayed on the display of modern technology. If the climate control device does not have a display, an error may be indicated by the indicator LED blinking or sound signals will sound.

Each equipment manufacturer has its own codes indicating malfunctions. To decrypt them, you can use the technical documentation for the equipment. The decryption can also be found on the Internet by entering the model of the equipment.

Knowing the error codes will help reduce the time spent searching for damage and try to cope with the repair on your own. But if we are talking about a serious malfunction, then it is advisable to contact experienced specialists. They know safety precautions and have instrumentation to diagnose equipment.

The table shows some error codes.Modern split systems have a self-diagnosis function, which allows you to more accurately determine the cause and location of the malfunction

Failure No. 1 - the system does not start

Most likely in this case there is damage to the electrical cable.

If there is voltage in the network, but the compressor, fans and indicators do not work, then you need to look for the problem in the following places:

• mains socket;
• cable and power plug;
• power connectors on the control board.

Most often, the reason lies in the lack of voltage, but it happens that the voltage in the network is not enough for the device to operate correctly. Most often this happens due to overload of the intra-house network. If the voltage in the outlet is about 220 V, then you should ring the power cord with the plug.

This can be done using a multimeter or a simple “diagnosis”. The cable consists of three wires. Damage to one of them can lead to a loss of power supply to the board and other parts of the split system. If the cable is intact, then you need to check the voltage at the point where it is connected.

Also, the reason for the lack of power supply to the equipment can be dead batteries in the remote control, a non-working remote control or a button to turn on the equipment.

Each malfunction has its own reason. And in order to detect it, it is necessary to follow a sequential algorithm of actions. Multimeters are the best assistants in diagnosing electronic and electrical components of equipment.

Failure No. 2 - water dripping

Many owners of split systems face this unpleasant problem. Most often, it indicates a clogged drainage pipeline.

The blockage can be of two types:

• mechanical — dirt gets clogged in the tubes;
• climatic — happens in the cold season, when some sections of the pipeline may freeze, resulting in the formation of ice plugs.

Mechanical contamination is extremely rare. In this case, you will need to resort to manual cleaning of contaminants, but you can use a compressor. Access to the drainage system tubes is provided at the fluid drainage point.

In the second case, you just need to melt the frozen sections of the drainage pipeline. For this purpose, you can use industrial or soldering hair dryers, but in severe frosts this procedure is not recommended.

If your split system does not just drip, but flows into the room, we recommend that you familiarize yourself with more detailed information about ways to eliminate similar problem.

Failure No. 3 - unpleasant odor

This indicates a clogged filter. When the air supplied by the indoor unit fan has an unpleasant odor, this indicates the beginning of the proliferation of various bacteria on the surface of the dirty filter. It must be changed immediately so that it does not lead to illness.

To prevent this condition of the equipment, it is necessary to dry clean the indoor unit once every two weeks. This applies not only to the external part of the equipment, but also to filters

But, replacing such a filter may not solve the problem with bad odor. This is due to the fact that contaminants may already be on other parts of the indoor module. Therefore, it is highly advisable to wash the main parts or order a comprehensive service.

Failure No. 4 - poor cooling

There are several types of such damage. Consider a situation with poor cooling coupled with dripping water.In this case, the main reason lies not so much in the clogging of the drainage system, but in the clogging of filters (coarse or fine cleaning).

Dust does not settle on the filter cloth, but is layered on the surface of the evaporator. This prevents the release of cold, which is why the fan supplies insufficiently cooled air. And the water drips because the pipes freeze or dirt gets into the drainage. The first case is the most common.

To fix this problem yourself, you need to clean the filters. To prevent the fabric from becoming deformed, you need to wash it under running cold or warm water, but not hot. You can use special detergents or disinfectants.

Dust from the pipeline can be blown off using a compressor or vacuum cleaner. Contaminants can be removed more thoroughly by completely disassembling the unit. But it is not recommended to do this without the proper skills.

In the case when poor cooling is complemented by turning off the compressor, the reason lies in contamination of the outdoor unit. If there is a lot of dust, fluff outside the room, or there is a highway nearby, then the radiator and condenser will quickly become covered with a layer of dirt. This causes the compressor to overheat, causing it to shut down.

The best access to the outdoor unit of a split system can be obtained if it is installed on the ground floor or on the roof. In other cases, servicing the external part of the equipment is problematic

Insufficient cooling causes difficult air exchange. This can be eliminated by removing all dirt from the fan, radiator and condenser. You can use soapy water and a brush, or you can use modern washing machines and steam generators.

The main thing is safety during work. Since the compressor-condensing unit is located outside the room, to clean it you will most often have to use the services of industrial climbers.

If the compressor runs constantly or with rare shutdowns, and the cooling is very weak, then this indicates lack of freon in the system. A small amount of refrigerant can be explained by two reasons: its leak due to mechanical damage to the pipeline or natural evaporation.

Since freon is a gas, it tends to evaporate even from non-working equipment. Accordingly, the correct solution in this case would be to fill the split system with freon of the required brand. You can find out the brand of refrigerant based on the information in the technical documentation for the equipment.

Freon is sold in special containers. But buying refrigerant is half the battle. It still needs to be filled into the system without exceeding the required volume. There are several refueling methods and they all require skills and special tools.

The easiest way is to fill the split system with freon by monitoring the pressure in the pipeline. This is done using a pressure gauge. We recommend that you read self-refueling rules freon.

Replacing freon yourself is the most labor-intensive process for owners of split systems. To do this correctly, it is advisable to have professional equipment

When the pipeline is damaged, then you need to find the fault. Sometimes this will require disassembling both blocks to find a crack or chip in the tubes. They can be soldered or replaced with new ones if there is a lot of damage and the tubes are in poor condition. After this, the climate control unit is refilled with freon.

Failure No. 5 - warm air supply

If the split does not cool, but rather supplies warm air, this indicates that the freon is boiling away before entering the evaporator. It boils away earlier due to clogged capillary tubes. A pressure difference occurs, as a result of which the refrigerant releases cold to the fan, and the fan supplies warm air.

In this case, the compressor can operate for a longer time or without turning off at all.

Capillary tubes are made of copper, so they are flexible and susceptible to deformation. This suggests that cleaning activities need to be carried out extremely carefully.

This problem can be solved by clearing the blockage or replacing the capillary tubes. The easiest way to clear clogs is with a compressor. But the compressed air may not be strong enough, especially if the blockage is complete or multiple.

In this case, you can resort to hydraulic cleaning or flushing the pipeline with special solvents. This often helps, but takes a lot of time. It is easier to replace capillary tubes, but this is an expensive service.

Failure No. 6 - hot air supply

The switched on heating mode when selecting the cooling function says only one thing: four-way valve faulty. The change of regimes depends on it. Such a malfunction of the split system is rare, and it can be eliminated on your own. You will need to find the valve.

Next you can do the following:

• repair - in most cases it simply jams and its operation can be resumed;
• replace with a new one;
• remove from system — by unsoldering it from the equipment, it will be possible to resume the supply of cold air, but you will have to sacrifice the heating mode.

In any case, it is not necessary to contact a specialist, except for ignorance of safety precautions and the basic elements of split systems.

Failure No. 7 - the compressor does not work

There are several reasons for this malfunction. This could be a failure of the compressor itself, a breakdown or loss of capacitance of the capacitors, or a breakdown of the thermal relay.

The compressor plays the most important role in the climate system. The performance of all equipment will depend on its serviceability. Therefore, situations with compressor overheating are unacceptable.

The most problematic case is failure exactly compressor. This is a rather complex and expensive device that is very difficult to repair on your own. Even experts will not always be able to help. Repair is only possible if the motor shaft is jammed. It can be wedged and work resumed.

We reviewed compressor diagnostic methods in this publication.

But, more often, the motor windings burn out - from overheating, vibrations, power surges or mechanical influences. In this case, only replacing the compressor with a new one will help.

You will also have to refill the system with freon. The cost of a new compressor including delivery, installation and refrigerant refilling will not be much lower than the cost of a new climate control device. Therefore, it is wiser to buy a split system.

It happens that the cause of the breakdown does not lie in the compressor. Any of the capacitors or thermostat, which can be replaced. These components are relatively cheap, and replacement does not require special tools. The main thing is to correctly identify the failed element and replace it with a similar one.

Starting and running capacitors rarely fail.They are widely available on sale. The main thing is to choose a component that is designed for the specified voltage and has the same capacitance as the damaged capacitor

Capacitors and thermal relays may become burnt due to poor contact or exposure to mains voltage surges. The capacitors may also show signs of swelling or electrolyte leaks.

This is the first sign of a problem. If there are no visible signs of damage, then every Check the capacitor with a multimeter.

Failure No. 8 - short duration of operation

If the split system works properly, but quickly turns off without reaching the desired air temperature in the room, then this indicates failure of one of the temperature sensors.

In the average design there are three of them: a thermistor in the internal block and one temperature sensor each for the evaporator and condenser. The breakdown of one of them leads to such operation of the equipment. They can be easily checked with a multimeter. They are cheap, and all you need to replace them is a soldering iron.

More rare malfunctions

Among these are: loss of communication between units, “glitches” of the indicator panel, failure of one of the fans, failure of the control board or inverter module.

Each such malfunction can also be solved. But they are extremely rare, especially with proper use of climate control equipment. If maintenance is carried out regularly, then breakdowns can be avoided for a very long time.

Timely maintenance of the indoor and outdoor units significantly reduces the risk of malfunctions. Well-functioning equipment allows you to enjoy a comfortable indoor temperature for a long time

The average service life of climate control equipment without breakdowns is 7 years. And proper care of the equipment can extend this time to 15 years.

How to avoid equipment breakdowns?

Climate control equipment is complex equipment that requires regular technical maintenance.

To avoid frequent breakdowns, you need to follow the basic rules for operating split systems:

1. Clean filters regularly.
2. Do not turn on the heating mode when the outside air temperature is lower than specified by the manufacturer.
3. Once a year, check the freon pressure in the system and, if necessary, refill.
4. Once a year, carry out a complete cleaning of two units of the system. For industrial premises, cleaning should be carried out at least twice a year.

If it is not possible to carry out comprehensive maintenance of equipment, then you need to independently clean the heat exchanger, which is located in the indoor unit, at least once a year.

To get acquainted with the features of self-service of split systems, please go to this link.

Another important aspect that influences the duration of trouble-free operation of climate control equipment is its installation. Installation should only be carried out by specialists. If installation has not been carried out correctly, this may cause unacceptable vibrations and mechanical damage.

Conclusions and useful video on the topic

We recommend watching the following video for a comment from a specialist cleaning the indoor unit:

Self-repair of climate control equipment is quite possible. The main thing is that this does not harm your health or damage your equipment even more.

If you have the skills, experience and tools, you can fix most of the existing breakdowns. But in case of complex malfunctions, it is recommended to contact specialized specialists.

Do you have a problem with your split system, but you just can’t figure out the cause of it? Ask your questions to our experts and other site visitors - we will try to help you figure out the cause of the problem.

If you want to supplement the above list of faults or add recommendations for eliminating them, please write this information in the comments block.