What Is An Aircon Capacitor And
How Is It Repaired?
Air conditioning is an essential part of our lives.
We need cool, refreshed air to make sure that our
bodies are comfortable all the day long. Therefore,
there is need to make sure that air conditioners are
maintained properly and regularly. In countries such
as Singapore where there is no winter or spring
(there is just summer), air conditioners are of
great use; they control humidity, temperature, and
air speed in an enclosed building. One of the most
important parts in an air conditioner is the
capacitor. The air conditioner (aircon) capacitor is
a very important device that can result in serious
problems if it is not working properly. This article
gives more insight on aircon capacitors and
highlights how they can be repaired.
What is an aircon capacitor?
A capacitor is an electronic device that is used to
store charge in an electrostatic field. An aircon
capacitor is used to stabilize voltage and give the
required jolt to start the motor in an air
An aircon capacitor also helps keep the air
conditioner running. In Singapore, most air
conditioner units come with three motors, and the
three motors are powered by use of an aircon
Therefore, if the aircon capacitor is not working
properly, then your air conditioner will not
function optimally and offer satisfactory cooling.
In other cases, the motors will not start and the
air conditioner will not work. In other words,
failure of aircon capacitors will result in
breakdown of air conditioners.
What do aircon capacitors do?
Aircon capacitors have three primary functions. As
explained above, they start the motors, aid in
signal processing and power conditioning.
What causes aircon capacitors failure?
The most common reason for aircon capacitor failure
is being overworked, that is, running the air
conditioner for extended periods of time. This
results in overheating of the AC and so, blowing up
of its fuses and capacitors.
This is most common in countries with tropical (hot)
climate such as Singapore. A blown up capacitor is
easy to notice. An air conditioner with a blown up
capacitor produces a humming sound and the fan no
Troubles from bad aircon capacitors
Most air conditioners with bad capacitors have
difficulties in starting. The compressor of the air
conditioner becomes difficult to start, hesitates
while trying to turn on, and finally shuts off
later. If one of the aircon capacitors have failed,
a motor connected to it may still attempt to run.
If this goes on, the motor begins to grow hot and
finally burns out. This would call for replacement
of the entire motor. It is advisable to stop trying
using the air conditioner when you hear the humming
sound caused by a bad capacitor. Instead, you should
check on repairs right away.
In many cases, a capacitor begins to make a clicking
noise before it fails. This acts as an alert before
the fans or the compressor stop working.
How to repair aircon capacitors
Now that you have learnt the effects and how to find
bad aircon capacitors, let’s look at their repairs.
In almost all the cases, capacitor problems call for
the capacitor to be replaced. If you know how to
replace aircon capacitors on your own, then you can
save a lot of money. The process is easy, however,
it needs a lot of attention. You will need a voltage
tester, a screw driver, a pencil, a new capacitor, a
mounting strap and your protective gear.
Before you set to replace a capacitor, you should be
well-acquainted with the safety and health
regulations about the maintenance and repair of
electric devices; working with electricity is
The following are steps that you can follow to
replace a bad capacitor
1. Put off the condenser
Condenser is the air conditioner box unit that
Have your protective gear on, find the condenser,
turn it off and use a tester to make certain that
there is no power in it.
2. Open access panel
After ensuring that the condenser has no power in
it, go for the access panel. It usually has a label
that has an electrical warning on it. Loosen the
screws and open it.
3. Get a new capacitor
After you open the access panel, you will find the
bad capacitor. You should easily find it as it has a
sticker and shaped like a can.Write down the
technical data of the bad capacitor. Such data
include its load voltage, tolerance, capacitance and
such. Use this data to buy a new capacitor with the
same characteristics. In doing this, the shape or
size of the new capacitor does not matter; the
performance properties do. The shape and size will
not affect its operation.
4. Check the connections of the old capacitor
Have a look at how the bad capacitor is connected
and note down the connection. The new capacitor may
need to be connected in the same way.
5. Connecting the new capacitor
When connecting the new aircon capacitor, you should
disconnect all wires from the bad capacitor and join
them to their respective spots on the new capacitor.
To avoid confusion, you can do this one wire at a
time. That is, you disconnect a wire from the old
capacitor, and then connect it to the new one before
proceeding to the next wire. After you have
connected all the wires, mount the new device in
place and make sure that it is stable. Also make
sure that the connections are firmly fixed at their
6. Check the condenser
Switch on the thermostat and watch the operation of
the condenser. If all is working well, then you may
cover the condenser. You can now use the air
conditioner once again. The above information will
help you discover when an aircon capacitor goes bad
before the motor blows out. The information will
also help you replace an aircon capacitor without
the aid of a professional and thereby, save you
However, it is always good to remember that you
should protect the aircon capacitor to prolong the
life of your air conditioner unit. The hot climate
in Singapore and the heat given out by extra-hard
working motors makes aircon capacitors to break
down. Therefore, it is recommended that you should
not run air conditioner for extended time periods.
I was recommended by my
friend Vincent to do my aircon repair. I find
them very professional in their work. The
technicians are friendly and also efficient. I
signed a yearly contract and i am very satisfied
with their service. Keep up the good work.
Miss Emma (Pasir Ris)
Specialising in all types Aircon
Servicing, Air-con Repair, Air-con Chemical Wash & Air-con
Singapore Leading Air Conditioner
Maintenance & Installation Specialists
We are specialists in Aircon Servicing,
Aircon Chemical Wash, Air-con Repair, Aircon Installation,
Freon Gas Topup & Air-con Overhaul