Air conditioner circuit board troubleshooting may sound simple and easy. But it is most definitely not so. For one, there is no direct way of knowing that the problem lies in the circuit board. You have to look for problems everywhere else first. Once you have exhausted all your options, only then it is time to consider the circuit board. Before we move on to the complex matters, let us tell a bit more about the circuit board.
What Is A Circuit Board?
A circuit board is also known as PCB or Printed Circuit Board. This board is the base for physically supporting and wiring the surface-mounted and socketed parts in electronic items, including air conditioners.
How Much Does AC Circuit Board Cost?
If you are a DIY kind of person, you can buy a decent Ac circuit board online for $50 to $250, and replace the old one yourself. However, if you call a trained technician to do the job, the replacement cost would be anywhere between $400 to $600.
Can AC Circuit Board Be Repaired?
It is possible to repair a circuit board, but that can only be done in a proper workshop and not on-site. Having said that, it is always better to buy a new circuit board rather than repair the old one because –
1. The repair job has to be precise; only then it is considered complete. The contact points on the circuit board are so small that chances of error are high.
2. There is also the possibility that other contact points may have weakened so much so that they have a high probability of failing soon.
3. Repairing a circuit board is an intricate job, so it takes time while a new one can be bought and replaced instantly.
Air Conditioner Circuit Board Troubleshooting
The circuit board though small in size, is very crucial to the working of an electrical appliance. Depending on the complexity of the work performed, these PCBs can be intricate or simple. Finding a fault in it is a step by step process. Most things will sound easy enough, but actually, involve a lot of technical know-how. Below is our air conditioner circuit board troubleshooting guide.
1. Your checks will begin by making sure that everything in the AC unit is working fine. Start with the basics like changing the air filters, cleaning the ducts, making sure the contactor is fine, the refrigerant is in adequate quantity and work your way to the issue. Obviously, what and where you look depends on the problem.
2. A circuit board needs power to work. Begin by ensuring that the circuit board is receiving power without interruption. Sometimes the power is drawn from line voltage, and at other times the circuit board gets its power supply from the control transformer. In either case, you need to make sure that the input voltage to the board is proper.
3. Next step is to check the output. Many AC circuit boards depend on a safety check prior to sending an output signal or voltage to the component that is connected to it. This usually involves a check through all the safety circuits. Once all the checks are passed only then, the board allows an output signal. If the limit and pressure switches remain open, the board does not allow an output signal to the connected component. In some circuit boards, you can override the safety circuits. Once that is done, and the AC unit starts operating normally, you know that the problem lies in the safety circuits. If the problem is indeed the safety circuits, do not assume it is because of a bad switch. Try to look for the root cause, which is what caused the switch to open. Searching for the answer is very technical work and involves a complete understanding of how the AC works. Since most of us lack this knowledge, it is best to call your local HVAC company to send their technician. They are skilled in finding such faults and will also take less time to do so.
4. If the issue is not in the safety switches, you need to look for other causes. To do so first kill the power to your AC. Now remove the circuit board carefully from the bracket or mounting pins and have a look at its back. If something on the circuit board has burnt, there will be markings on the back. If you find the burn marks, it is time to replace the circuit board with a new one. Before disconnecting anything from the circuit board, take a picture. This will make the reinstalling work easy. Acting as a reference, the picture will tell how to connect the terminals.
5. On an air conditioner circuit board, there are relays. These look like small black cubes. The work of a relay is to send power to the condenser fan motor or the blower motor. If the fan does not start, the AC does not work. So, take a screwdriver, and gently tap the little black cubes with its handle. Many times, the relay contacts that are inside the black cubes stick. Tapping helps to release them, and they open and close as needed. If tapping does not release them, you need to replace the circuit board. Again, take a pic so that you know what goes where.
Air conditioner circuit board troubleshooting should be undertaken by yourself only if you have the necessary knowledge. Having confidence, but no knowledge can prove to be perilous. When dealing with electronics, remember you can cause harm to yourself as well as your machinery through half baked information. These jobs are best suited to people who are trained for them. The guide above gives you a fair idea of the steps involved in air conditioner circuit board troubleshooting. So, when the technician comes, you will know exactly what will be the sequence of steps they will be following in locating the problem. Having this general idea gives you the power to ensure that the technician does a good job.