A Troubleshooting Guide to Split Air Conditioning Control

A split air conditioner is known as a mini-split or ductless split when the outdoor unit gets separated from the indoor unit. The outdoor unit composes of a compressor, the condenser, and a fan. The heat is transferred from the indoor unit to the outdoor unit, blowing it to the surroundings.

Split Air Conditioning ControlThe indoor unit compromises of an evaporator, a fan, and an expansion valve. Copper pipes connect the flow of refrigerant between the indoor and the outdoor unit.

The split air conditioner consists of an ON/OFF compressor where the compressor is either ON entirely or OFF thoroughly. The inverter type compressor can adjust the speed of the compressor depending on the needed load.

Here is a DIY guide to troubleshooting common problems with a basic split air conditioner that will help you to understand more of the electronic part of the equipment.

Alert! You need to have a good electrical knowledge the repairing stuff. It is a best practice to disengage and isolate the power supply when you are troubleshooting the control board. You should probably hire a qualified technician to check your unit.

Main Control Circuit Board

The main control board classifies into input power supply and output power supply. The input includes a microcomputer, controlled integrated circuit and temperature sensors. The output controls a compressor, outdoor fan, indoor fan and air swing. The Ac input in the primary circuit needs to be converted to DC voltage so it can power the drivers and circuits.

Infra Red Receiver Board

To control the handheld remote to send the settings to the controller at the air conditioner there is an IR circuit board that receives the signals. The receiver fits at the front of the indoor unit. And it can be verified by a special sticker that allows the IR frequency to pass.

Handheld Remote Control

It is known as the handset. The handheld board is the place where you can control the AC settings easily by moving your controller towards the air conditioning unit. You can control the Temperature, operating mode, timer, swing air direction, energy saving function, the fan speed, ionizer and the sleep mode. These features are commonly available depending on the manufacturer of the unit.

Common Problems and their Diagnosis:

  1. The wire may get burned due to lightning, short-circuiting of live-neutral or surge of power lines. You need to check whether the fuse, varistor or the transformer burned.
  2. The Air conditioner may not work if the fuse blows, varistor gets heated, transformer burns or the transformer pad lifts. You need to use the test pen to check the availability of power supply. Then use a multimeter to examine the power supply.
  3. The controller may get tripped after a few hours due to over current. Check it by referring to fuse ratings of distribution.
  4. The control may lose sensitivity due to the wrong location of the thermistor. You need to check thermistor to check return air.
  5. The sensor wire loses down if the crimping is incorrect. Check the resistance of the thermistor.
  6. The PCB becomes noisy if the buzzer blasts. Switch the unit off and then test the bell.

These are the common problems with the board and the ways to troubleshoot them.