The following information is provided solely for your knowledge. We do not recommend
you do your own repair work as air conditioning systems require trained professionals to
handle repair and maintenance issues. However we are sharing the below so you can know your
air conditioner system better. Should you decide to follow the steps below, Aircon.guru will
not be in anyway responsible for any injury to any being or damage to
Air conditioning systems generally have 2 separate portions,
which are the condenser and the evaporator. The condenser unit is normally placed outside the
house on a level ground like a concrete slab. The evaporator coil is hung above the furnace.
These are the typical cases where the air conditioning system does not work:
Warning – Power to the air conditioner must be switched off before any work is to
proceed. Cleaning of the Evaporator
- When the air conditioner works but the apartment is not cold, the problem is probably in
the distribution system.
- As these 2 portions, evaporator and condenser are enclosed, you should engage a
professional servicer to come and inspect for any issues or maintenance. However you
still can follow these guidelines to maintain your system at the optimal condition for
evaporator might be a sealed unit thus it may not be easily accessible for cleaning or other
purpose. However if it is accessible, the following cleaning process is the usually performed:
Maintaining the Condenser
- Take away the foil or the plates covering the system.
- Clean under the evaporator with hard bristles. A small mirror maybe required to help
with the viewing of the underside. Be careful not to bend the pipes connected to the
- Clean the container under the evaporator that holds the water that has condensed from
the unit. If the days have been humid, the drain and pan should be checked regularly as
if there is too much liquid the drainage system maybe clogged.
- Put back the condenser unit and replace the foil and the plate.
- Turn on the air conditioner to check for air leaks. A masking tape can be used to cover
up the hole.
As the condenser is usually placed outside of the
apartment in most of the air conditioning systems, dirt, dust and other unwanted things get
stuck on it. The condenser should be maintained by cleaning the fan inside, so as to maximize
the cooling effect. The typical maintenance steps are as per outlined below:
Handling of the Refrigerant
- Remove any vegetation if any has grown around the condenser unit as this is blocking the
- Using a coil cleaner that can be purchased at hardware stores or refrigerator supply
stores to clean the condenser. The instructions on the cleaner should be followed
carefully. The condenser should be left to dry after flushing the coil clean. Do not
hose down the condenser.
- Use soft bristles to take away the dirt stuck around the condenser fins. However do not
use a hose to try to clear the fins as the water can make the dirt into mud and these
will stick to the fins. It is recommended to use a fin comb if necessary. Fins are
delicate so be sure to be gentle in this step.
- It is important that the ground the condenser is sitting on is even. The surface should
be flattened if it is uneven.
- If the air conditioner is used in a location where there are different seasons, be sure
that the condenser unit is well covered to prevent damage from the weather such as
fallen leaves which will block the air flow or ice forming that will damage the unit
during the different seasons. You can purchase a condenser cover from the stores or just
use a heavy sheet with strong cords to secure the unit.
The refrigerant for cooling purpose in the
standard air conditioning systems is known as Freon. The amount of Freon in the air conditioner
is critical for proper cooling to occur. If Freon is suspected to be the cause of the problem,
always call a trained technician to assist in recharging the system. You should never try this
on your own if you are not trained. One can do a visual inspection of the coolant tubes that is
running from the condenser (outside) into the evaporator located inside the apartment. One major
issue will be if the insulation of these lines is torn or worn from years of usage, this will
reduce the cooling effect of the apartment. You can experiment to replace these damaged coolant
line, by following the manufacturer’s installation instruction. Troubleshooting
of Window Air Conditioning System
Window airconditioners are individual units set
up in rooms to cool the enclosure.
Dirt and dust is the major maintenance issue for this
kind of airconditioning system. These particles reduce the efficiency of the evaporator, disrupt
the airflow of cooled air into the room, get stuck in filters and block drainage system.
advantages of this system is that minor repairs can be performed by the owner, and that if any
big repairs are required, you can always take this air conditioner out of the mounting and bring
it to the repair shop yourself to save on cost. Another advantage is that this being a small
unit, it can be removed and stored if no longer in use or easily covered up to protect it from
external elements. One example would be during winter, air conditioners would not be required
for use. Warning: Always unplug before performing any work on a window
air conditioner, or any air conditioner for that matter. This kind of air conditioner has 1 or 2
capacitors and they store electricity even with the power source switched off. Thus, always
switch off, unplug the air conditioner, and discharge the capacitor by following strictly the
manufacturer’s manual otherwise one may receive a severe shock. If in doubt, always engage a
trained professional to do the job.
Regular maintenance of major parts of the air conditioner can
extend the lifespan of the air conditioner system and prevent bigger problems. Here are some
guidelines.Note: Aircon.guru is not responsible for any damage to any equipment
or injury to any being should you decide to perform such checks yourself.
The filter should be cleaned or replace every month,
especially in Singapore where the air conditioner is used often. In dusty places, this should be
done more frequently. Some air conditioners contain a reusable and washable filter. This filter
should be cleaned with a diluted cleaning detergent solution and rinse well after cleaning. The
filter should be dry before putting it back into the air conditioner. Power
One of the issues that the air conditioner will not start up is when the power
cord is worn out and thus unable to start up the unit. This power cord links the air conditioner
to the wall outlet. A professional should be able to check the functionality of the cord with
test wires and a volt-ohm-millammeter (VOM). A reading of ‘0’ means the cord is working; any
number higher, the cord is no longer functioning and needs to be replaced. Evaporator
and Condenser Coils
Just like the filter, these parts needs to be clean every
month, and more often if the location is dusty. A vacuum cleaner usually can do the job. A fin
comb can assist in getting rid of the dirt in between the fins on the coil. Switch
Behind the control panel lays the selector switch which is responsible to turn on the air
If the air conditioner is getting power with the switch turned off, it means
the switch is faulty. The typical reasons are that the insulation of the switch terminals maybe
burnt. You should engage a professional to change the switch if there are burnt marks on the
The thermostat and the drain ports are critical especially for the window
air conditioning unit. The guidelines as follow: Thermostat
the control panel lays the thermostat. This is how it is tested and/or replaced if it is faulty.
- Take out the grille and control panel from the air conditioning system. The thermostat
has a sensor attached, and this sensor is extended into the evaporator coil area. The
function of this sensor is to react to temperature changes, which is controlled by the
- Delicately remove the thermostat and remember its location.
- Test the thermostat with VOM to ensure it is functioning.
It is important to note the above is for a simple thermostat. If there is 2 or more lead wires
connection, a professional should be engaged. Drain Ports
ports are an opening where the condensation of the water from the evaporator coil collects.
ports can easily be filled with dirt and this can cause water to drip from the air conditioner.
Thus it is important to ensure the drain ports be unclogged for the best performance. You can
use a piece of wire or a small knife to clean the ports. This should be done every month or more
frequently depending on the environment. Fan
When a fan
malfunctions, the problem is usually loose or dirty blades. If the fan won't operate or if it's
noisy, cleaning and tightening will usually fix it. Here's how to repair a room air
Motor and Compressor
- Open the air conditioner and find the fan
- Clean the fan with vacuum and cloth
- Inspect the fan blade on the motor shaft to see if any blade is loose. If there is,
tighten it. Vibration can usually loosen the bolts and nuts.
- If the fan has oil ports, put a few drops of 20-weight motor oil to each oil port every
- To test if the fan motor is spoilt, use the VOM set. If VOM is reading between 3 and 30
ohms, the motor is working well. A reading of 0 or extremely high, the fan motor is
faulty and needs to be changed. A professional should be engaged to replace this motor.
This should be checked by a professionally trained