We are so used to living in an ideal climate-controlled environment in our homes that it does not matter how the weather is outside. It may be blazing a winter storm outside, but you would be enjoying a warm summer-like climate inside the home and vice-versa. All these thanks to the modern air conditioners. Today’s air conditioners give cool air in summers and warm air in winters, thereby keeping the home comfortable pleasant all year round. A machine which is used so often can suffer breakdown due to a multitude of reasons. One of them being a fried circuit board. Through the medium of this post, we shall try and educate you more about its causes and how to bypass the AC circuit board.
Causes Of A Fried Circuit Board
The common causes which can burn or fry a circuit board are –
1. Power Surge – When there is a power surge, the circuit breaker should trip. If that does not happen, the circuit board can fry because of high voltage which it is unable to handle.
2. Wrong Fuse – The kind of fuse that is used in your AC depends on its power. If a small fuse is installed, it will be unable to handle the load of your AC and in turn, fry the circuit board.
3. Loose Wire – Wires which are not fitted or appropriately tightened can cause a short circuit. When that happens, the probability of the circuit board to burn increases.
4. Clogged Filter – Accumulation of dirt and debris over a period of time clogs the air filters. This puts tremendous pressure on the blower motor. As a result, it overheats and burns the fuse which can again make the circuit board go bad.
5. Faulty Capacitor – If the starting capacitor itself is not working properly, it puts a strain on the entire unit. One of its effects could be a burnt circuit board.
6. Weak Blower Motor – Sometimes the blower motor fails. When it fails, the fuse blows, and the AC unit draws too much power. This high power causes a short circuit and burns out the circuit board.
How To Bypass AC Circuit Board
It is highly recommended that you do not bypass the AC circuit board without good reason. Even then, it is advised that you let a trained technician do this job.
For your knowledge, let us understand what exactly needs to happen so that your AC starts giving cold air.
1. First, what needs to turn on is the condenser.
2. The second thing needed is the blower motor.
First Step – Open the fuse box in your home and identify the AC’s circuit breaker. Flip this breaker to the “Off” position. If you are not sure which particular breaker is for your AC, turn off the main breaker which supplies power to your entire home.
Second Step – As a precautionary measure, locate and turn off the power switch that controls the outside compressor unit of your AC.
Third Step – First thing to check is that the transformer is providing a current of 24 volts. If not, you may either replace the transformer or connect it directly to the line power.
Fourth Step – Attach one side of the 24-volt wiring from the transformer to the wire that goes out to the contactor of 24-volts. You can find it in the outside ac condenser unit. If there is a blue wire, use that one to complete this step.
Fifth Step – Attach the other side of 24-volts from the transformer to the red wire. Ensure that the other end goes to the R terminal, which is in the thermostat.
Sixth Step – The next step is to ensure that the other side of the contactor in air conditioner connects to the Y terminal of the thermostat. For this, use the yellow wire. Ideally, it should already be that way. If it is not, you will have to make it that way.
Seventh Step – Connect the high volt, line-in, power directly to the blower motor. This will get the blower motor running continuously to keep your home cool.
Eighth Step – Flip the main circuit breaker or the AC specific circuit breaker back to “On” position, as the case may be. Also, turn on the power switch to the outside compressor unit.
Bypassing the AC circuit board is only a temporary solution. It should suffice until you are able to buy the requisite circuit board to replace the one that fried. Do not use this as a permanent solution.
AC Circuit Board Troubleshooting
In an AC, you need to have proper input in order to get the desired output. However, this is one aspect which is based on technical knowledge. A regular person with no electronics or engineering background will find it challenging to analyze this. Further, whether the problem arises due to a bad circuit board or something else entirely is also tricky. A trained HVAC technician can do this analysis in just a few minutes rather than the hours that you would take. Moreover, they can identify the problem correctly and advise you the best course of action as well. In the interim, if required, they can also give you options which can have you continue living in comfort until the necessary repairs or replacement can be carried out.
How to bypass AC circuit board may seem as simple as disconnecting a few wires and reconnecting them elsewhere. But, do not be fooled by the simplicity of the steps involved as there is no scope for error. Your AC is a piece of expensive machinery. Your mistake may fry your AC beyond repair. That would be a costly blunder. Let people who are trained for these jobs handle the sensitive issue. From your end, all your AC demands are gentle cleaning and regular maintenance from trained personnel. Other than that, you need to just sit back and relax in the cool air of your air conditioner.
Frequently Asked Questions – FAQs
You can bypass the AC circuit board, but it is highly recommended that you do not do it without a solid reason. If you must, only let a trained technician do the job. It is not a DIY activity.
The main reason behind premature circuit board failure is ESD or Electrostatic Discharge at the time of assembly. There are other reasons as well, like:
1. Exposure to intense heat.
2. Accumulation of dust over the contact and the circuit board itself.
3. A power surge or overload.
4. Excessive moisture.
5. The accidental impact that happens in a drop or fall.
Circuit boards burn due to:
1. Power surge.
2. Taking on too much load.
3. Worn out components on the PCB.
4. Abnormally high temperature or humidity in the environment.
After turning off the power supply to the outdoor unit, attach one side of the 24-volt wiring from the transformer to the wire that goes to the contactor (blue wire). Connect the other side of the transformer to the red wire, ensuring that one end goes to the R terminal (thermostat). Connect the other side of the contactor to the Y terminal of the thermostat (yellow wire). Attach the high volt, line-in power to the blower motor. Finally, flip the AC circuit breaker back to the “On” position. This is all it takes.
Bypassing a broken circuit board is a job for professionally trained technicians only. It requires technical knowledge and skill to complete the job safely and perfectly. Therefore, if your AC demands it, do not do it yourself. Instead, call a professional HVAC technician, and they shall do the needful.