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why your ac unit is not working

Reasons Why AC Unit Is Not Working Properly

 |  Air Conditioning, Blog, General Home Care, HVAC

Air conditioning equipment are usually reliable. Yet as with other important and expensive appliances, it does encounter electrical and/or mechanical problems from time to time. Here are six of the most common issues with central HVAC systems that can keep the outside ac unit not working correctly.

  1. Refrigerant Leak in the System
  2. The Unit Blows Warm Air
  3. The Unit Will Not Turn On/Off or Cycles Frequently
  4. Clogged Condensation Line
  5. Frozen AC Unit

The Unit Does Not Go On

Sometimes an A/C system will not come on in the early days of the hot season. This could be because it is not hot enough outside for it to work at the thermostat level you have set or the thermostat has stopped working altogether. Another problems that can occur is the unit not receiving enough power from the electricity source.

Determine first whether or not the thermostat is working properly. It can take up to several minutes for your unit to activate once you adjusted the settings properly. If you are in need help operating or calibrating your thermostat, then call an A/C technician to ensure you are using the equipment properly.

You also need to determine that the unit is getting enough electricity. To do this, find the fuse panel. Make sure the circuit breaker on the HVAC unit has not been tampered with. If a fuse has blown, you can easily be replaced. Otherwise, reset the circuit breaker as necessary. There could be a circuit breaker panel just outside the unit as well. Check that the quick disconnect is properly inserted. It will require the services of an A/C tech if the electrical issues continue.

Refrigerant Leak in the System

One of the most frequent problems in summer and springtime proves to be a system refrigerant leak. Adding refrigerant coolant is only a band-aid, temporary fix to the problem. It ultimately requires having the leak fixed by repairing the copper line or replacing the coil. HVAC units should not leak coolant, so do not neglect to get this fixed, preferably sooner than later.

The Unit Blows Warm Air

Dirty filters can cause your air conditioning unit to blow warm air instead of cold. The flow cool is not able to successfully make its way through the air ducts, thanks to the dirty filters. Clean air filters not only all to cold air to flow efficiently, it also acts as a safeguard allowing the rest of the equipment perform correctly.

This becomes especially critical during the summer months when temperatures can be well over 100 degrees. It forces the A/C unit to work harder in order to make cool air. Check the conditions around the outside ac unit. Be certain that trash, leaves or other debris does not obstruct the air intake flow. Those units which blow warm air can also be signaling an inadequate amount of coolant is in the system. It requires a licensed HVAC technician to refill the refrigerant in the system.

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The Unit Will Not Turn Off or Cycles Frequently

These units can also run without stopping, which is the opposite problem of an ac compressor not running. If the unit is insufficiently sized to cool the square footage inside your home, it will run continuously in a vain effort. Another problem can be that the outside fan keeps running, even when the thermostat is off. In an effort to turn off the fan, turn off electricity to the system. You can do this by turning off the appropriate circuit breaker. A final culprit could be that you have failing switches or low levels of coolant which can lead to the unit running without stopping. An HVAC tech can do the repairs for you.

Regarding continuously cycling, it could be the air conditioning unit is not the proper size for your home. This will cause it to cycle off and on repeatedly. When the unit is working properly, it will attain the set level from the thermostat and will cycle on and off at the assigned times. Then as the temperatures decline below the thermostat settings, it forces the unit to cycle back on again. Depending on the placement of your thermostat, you can also experience frequent cycling as the air register blows cool air right on to the thermostat.

Clogged Condensation Line

There are condensation lines in these HVAC systems. The interior parts are sitting within a drip pan that is intended to gather water as the drain line of the condensation unit gets clogged too much. If insects move into your drain line and build up a nest, then these will be unable to function properly.

Visible water in this pan needs compressed air forced through the pipe so that the obstruction will be removed. You should also ready a special mixture of half bleach, half water. You need to pour it down the drain pipe so that all mildew and mold will be removed. If this does not accomplish the result, then you will need to contact a reliable A/C repair tech.

Frozen AC Unit

There is a range of issues that can lead to HVAC units freezing and the ac compressor not running. For example, it can be an irregular airflow that can keep the system from functioning properly. You can address this by checking all filters and replacing (or cleaning) them as needed.

The coils also need to be debris and dirt-free. Obstructions must be removed from air intakes. If the blower fan malfunctions, then these systems can freeze up and cease working. This would cause the colder air to become trapped in the HVAC unit until the point that the coil freezes up.

Another issue is that there might be a failing control relay. This would mean that the outside unit keeps running while the inside unit turns off. It is true that owners of the home can remove debris and even change air filters on their own. Yet replacing the major electrical parts definitely needs the attention of a certified A/C tech.

The last thing to keep in mind is that numerous studies have been done on cooling and heating equipment. These studies show that routine HVAC unit maintenance and checks will stop the majority of issues from interfering with air conditioning units. For those other problems that crop up, a skilled A/C technician is the answer.

Isley’s has someone on call 24 hours a day, 7 days a week, 365 days a year. No matter when you call, an Isley’s team member answers and gets a qualified A/C tech out right away give us a call at (480) 422-5949.

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