Ductless AC Troubleshooting Guide

Resolve Common Ductless AC Problems

While ductless heating and AC systems are designed to provide continued comfort for your home for years, you may eventually run into an issue with your system. Most issues are relatively minor and can be addressed with a few simple fixes. If, however, your system isn’t working at all or is experiencing some other major problem, call Dr. Ductless for professional ductless AC repairs in Los Angeles and throughout the surrounding areas.

Browse our ductless AC troubleshooting guide for solutions to common ductless problems, or call to schedule repairs with our highly trained team!

Problem: The Unit Won’t Turn On Right Away

Most ductless heating and AC systems have built-in protections to prevent fuse blowouts. If you turn off the system and then immediately turn it back on, the compressor (the indoor unit) may not start for approximately three minutes to avoid a fuse blowout. Alternatively, if there is a power outage or power is otherwise interrupted, the unit’s protection circuit may delay re-starting for a period of three minutes once power has been restored.

Problem: You Can Hear Noises Coming From The Unit

Though ductless systems offer very quiet operation, a certain amount of noise emitting from the unit is normal and to be expected. Immediately after you turn on the compressor (indoor unit) and for a few minutes afterward, you might hear a noise that sounds like water flowing through the piping. This is, in fact, the coolant flowing through the unit. The same noise can sometimes be heard during operation, as well as immediately after the unit is turned off and for a few minutes afterward.

When the unit is running, you may also hear a minor squeaking sound. This is typically just the front panel/cover expanding and contracting slightly due to the changes in temperature.

Problem: The Indoor Unit Is Emitting Unpleasant Or Unusual Odors

Some smells, such as a smoky or musty odor, may simply be due to environmental factors. If you smoke indoors, for example, the unit may take in tobacco odors and/or smoke which can then be emitted back into the room. Pet dander, dust, and mildew can also lead to a unit that produces unpleasant or unwanted odors.

Problem: Steam Or Mist Is Coming From The AC Unit

When your system is set to cooling, the indoor unit may produce a very slight mist. This occurs as a result of condensation that forms when the air inside the room is suddenly cooled. When the system is set to heating, the outdoor unit may produce a small amount of steam. This usually occurs when the outdoor unit’s fan stops as a result of the automatic defrosting feature.

Problem: Your System Has Weak Airflow Or No Airflow At All

Weak or nonexistent airflow may be a symptom of several things. If your system is set to heating, you may experience weak or no airflow immediately after starting the system, as the internal fan speed can be very low initially to allow the various components to warm up. Additionally, while heating, the outdoor unit may stop if the internal temperature of your home rises above the temperature set on your thermostat. This will prompt the indoor unit to reduce the fan speed. To boost airflow, simply turn the thermostat to a higher setting.

Most ductless systems have an automatic defrosting mode designed to protect the various components of the system. When the system switches to automatic defrosting mode, it will stop temporarily—usually for a period of about 7 to 15 minutes. When this occurs, an “operation” indicator light will turn on or flash, alerting you that the system is in automatic defrosting mode.

You may also experience lessened airflow when the system is operating in “dry” mode or when it is monitoring the ambient temperature. If your system is set to “super quiet” mode or “auto” operation, the fan speed will also be reduced. If your system has a weak or nonexistent airflow, check these settings first to determine if you really need ductless heating or AC repairs.

Problem: The Outdoor Unit Appears To Be Leaking

During automatic defrosting mode, the outdoor unit may produce a small amount of water. This is normal and nothing to be worried about. However, if you notice any signs of a refrigerant leak, be sure to call Dr. Ductless for prompt ductless heating and AC repairs in Los Angeles and the nearby areas.

Problem: Your System Isn’t Working At All

One of the most common reasons we are called for ductless repairs is due to systems that simply won’t turn on. A non-operating unit could be the sign of a serious issue, but it could also simply indicate a minor problem. Before calling our professional repair team, first check to see if there has been a power outage or failure or if a fuse has blown or a circuit has been tripped. You may need to reset the fuse or circuit to get your system back up and running. If this doesn’t solve the issue, check to see if the system’s timer is operating. If so, it may be the reason your unit has turned off.

Problem: The System Isn’t Heating Or Cooling Your Home Enough

Poor performance can be the result of several things. First, check the air filter to see if it is dirty or clogged. Air filters should be changed regularly, especially with frequent use, as a dirty air filter can seriously impact your system’s performance.

Next, check to see if the system’s outlet port or intake grille is blocked, dusty, or dirty, as this can also inhibit performance. If the outlet port and intake grille are both free and clear of debris, check to make sure that the system is not set to “super quiet” operation and that the temperature setting on the thermostat is not too low or too high.

Several environmental factors may also affect the overall performance of your system. If your system is not effectively heating your home, make sure there are no open doors or windows and make sure that any drafts are properly addressed. If you are not getting the cooling power you need, check to see if nearby windows are allowing bright sunlight into your home. If this is the case, you may want to consider installing blinds or heavy “blackout” curtains which can keep on any unwanted light and heat. Too many people in one area can also make the room warmer, as can multiple computers, heating apparatuses, and similar items.

Problem: The Remote Control Is Not Working

First check to make sure the remote control has batteries, that the batteries are not dead, and that they are loaded correctly. If all of these steps are taken and the remote control is still not working or is not working effectively, you may need to call for professional repairs.

Have an issue with your ductless system? Call Dr. Ductless at (213) 916-0005 or reach out to us online for fast ductless heating and AC repairs in Los Angeles!

Daniel Rose

Our consultant, Edson, was professional and knowledgeable. He helped us weigh our options for our AC needs, and we'd be happy to work with him again.

Charles Minsky

Dr Ductless arrived at exactly when they said they would, they serviced the ductless heater/ air conditioner and left it all in great shape

Andie Ximenes

Extremely professional, great crew that is knowledgeable, respectful, and timely. Deep explanation of everything that they were gonna do as well as explaining how the system works and how to maintain it.

Leila Day

Great team, great communication and beautiful work and care for my home. Would highly recommend. The new units are a huge improvement !

tishika burks

Matthew was very friendly, knowledgeable and I loved that he asked if we were familiar with the product. He also went so far to ask what our vision for the product was before he gave us our option. He didn't force his design on us like people has done before on other projects. I would recommend

Patricia Joyce

Israel is professional and did great work.

Jim Martineau

5-Star Review: Dr. Ductless is Outstanding — We’re SO Happy! We just finished a full Mitsubishi MXZ-5D42NL multi-zone heat pump installation (3 cassettes + forced-air handler with 8 line sets) and are very pleased. This system is super quiet and effective — the best AC and heating all in one. From day one, owner Matthew Alba was professional, respectful, kind, and truly attentive. He listened carefully to our particular needs and desires, then guided us to the perfect system and setup for our home. His expertise and care made the whole decision process easy and enjoyable. Lead foreman Angel (and the entire installation crew) were fantastic. Angel is extremely professional, knowledgeable, kind, and hardworking. The rest of the team was amazingly skilled, worked together like a well-oiled machine, and made the job run smoothly and efficiently. They were all a pleasure to have around — we actually looked forward to seeing them each day. A huge shout-out to Karina and the rest of the office staff too. They were totally on the ball — checking in often, answering every question, and providing all the information we needed. Their coordination made the entire project seamless from start to finish. Dr. Ductless truly shines. We’re very happy with the quality of work, the attention to detail, and the way they treated us like family. We will always use them from now on for any AC or heating needs. If you’re looking for a trustworthy, top-tier HVAC company, look no further — these folks are the real deal. Thank you, Matthew, Angel, Karina, and the whole team!

Ronaldo San Jose

Matthew arrived on time and was very thorough in explaining the service and equipment involved in my project. He was professional and knowledgeable and is highly recommended. Go to him for all your HVAC needs.

Denise Mazzotta

Matthew was very knowledgeable and informative! It was a consultation…not a completed project.

Ductless AC Troubleshooting Guide

Ductless AC Troubleshooting Guide

Have an issue with your ductless system? Call Dr. Ductless at (213) 916-0005 or reach out to us online for fast ductless heating and AC repairs in Los Angeles!

Have a quick question? We can help.