If a 4250 error code is displayed on your Mitsubishi air conditioner, it means that there is an issue with the power supply to the unit.
Seeing an error code on your air conditioner may be distressing, but these codes are actually meant to make troubleshooting much easier and quicker.
The 4250 error code that appears on some Mitsubishi air conditioners indicates an overcurrent electrical fault with the compressor or inverter. This error code is meant to protect your air conditioner from further damage.
The usefulness of air conditioner error codes
Seeing an error code blinking on your air conditioner can be quite distressing, and in most cases, highly inconvenient if the appliance refuses to work before this error is fixed.
But as infuriating as this can be on a hot day, these error codes are actually there to make your life easier.
If all of your air conditioner’s sensors are functioning correctly, an error code will only appear when there is genuinely an issue somewhere within the air conditioning system. These codes make it so much easier to diagnose, and even to fix this issue.
Mitsubishi air conditioner error code 4250
Modern air conditioners are not only built with all of the necessary sensors and components to help the air conditioner function as effectively and efficiently as possible.
They also have secondary sensors and components which can pick up when something is just not right with the way that the unit (or one of its components) is functioning.
Although error codes seem like a great inconvenience when they first appear, responding to these error codes and fixing the underlying issue can actually be a great way to avoid more damage later on.
This is especially true when it comes to electronic faults. The 4250 error code on Mitsubishi air conditioners is indicative of an overcurrent or power supply issue in the inverter or compressor.
If your air conditioner is displaying this 4250 error code, there is likely an issue with the electrical power supply to this component of the unit.
Moreover, since this issue usually requires that you carry out an inverter output test and various electrical checks on the compressor, many homeowners who are not skilled electricians themselves often opt to hire a professional to come out and take a look, instead of attempting to fix this issue themselves.
However, it always helps to have a deeper understanding of why an issue is occurring, what it means and what to do, before you jump right to the final steps.
What the 4250 error code means
When your Mitsubishi air conditioner detects that there is some kind of fault which is affecting the power supply to or from important components, the appliance will cease normal operations.
This is done to avoid causing any additional damage to the wiring or the components that may be caused by this fault.
In most cases, the 4250 error code means that the power supply to the compressor or inverter is very poor, or it is becoming unbalanced between phases.
When to call in the professionals for help
It may seem unnecessary to call in a professional for a 4250 error code. But it can often be difficult to find and fix these kinds of electrical issues if you do not have the necessary electrical skills and knowledge.
If you notice that the breaker your air conditioner’s breaker keeps tripping or if you notice any loose wiring, it is safest to call a professional for assistance, as this may signify a persistent problem.
What to do when your air conditioner is displaying a 4250 error code
If, you are confident in your electrical knowledge, though, the best thing to do in this situation is to consult your air conditioner’s owner’s manual for all the correct testing steps specific to your model.
However, if you are really in a bind, you can assess whether you have what is called a “floating neutral” (a poor connection to the neutral line).
To do this, you need to complete the following steps:
- Step 1: Ensure that the system is on standby and that the compressor not running, then measure the following using a voltmeter:
| The voltage between earth terminal and neutral terminal (outdoor unit) | This should be < 1V |
| The voltage between earth and each phase
And then neutral to each phase |
These readings should all be similar (give or take a few Volts) |
- Step 2: Make sure that the compressor is running and repeat all of the above measurements
If these readings drop when the compressor is running, there is almost certainly an issue with the power supply, and you should call a professional for assistance.