PTAC Unit Smells Musty – Why And What To Do?

May it be a residential or a commercial area. Nonetheless, a PTAC unit that causes a musty smell inside your place can be a real bummer. However, you don't know why this issue happens and what proper actions to take.

Well, you've come to the right page! As we've done in-depth research about this topic to assist you. Let's check out the answer below!

A musty smell in your PTAC unit can be due to several factors. The major causes of this issue are using a PTAC with a dirty filter and a clogged drain line.

Regularly cleaning your PTAC unit can fix the issue or prevent it from happening.

Throughout this article, we will talk about how PTAC functions. We will also teach you how you properly clean its several vital components. So stay on track to know all the relevant knowledge about this topic. With that said, let's get start the discussion!

New PTAC packaged terminal air conditioner unit covered with rear grille installed through a commercial building exterior wall. Electrical conduit pipes and boxes on unpainted wall surface. PTAC Unit Smells Musty - Why And What To Do?

How Does A PTAC System Work?


PTAC is short-term for 'Packaged Terminal Air Conditioner.' It is an independent type of heating and cooling system. They use electricity as their main power to move the refrigerant from the unit to remove heat and humidity.

You've likely seen one if you've ever observed them in a hotel or motel. The PTACs are typical in residences, dormitories, apartment complexes, and other types of businesses without central air conditioning.

PTACs are the ideal solution for delivering reliable, energy-efficient, and user-friendly comfort to any place. Additionally, most PTACs now offer heating choices, saving you the expense of buying a new heater for the winter.

How Do I Clean My PTAC Units Inlet Air Filter?

Hands of a male technician repairing an indoor air conditioner using a screwdriver. Maintenance of air conditioners
Hands of a male technician repairing an indoor air conditioner using a screwdriver. Maintenance of air conditioners

A clean PTAC unit will operate effectively and eliminate any bad odor circulating in your system, especially if running in dusty, dirty places or conditions.

You should always turn OFF the unit's power supply before you proceed with cleaning the inlet air filter.

Use this cleaning procedure we provided below to clean your PTACs air filter properly:

  1. Grab the top intake louver to release the intake grille.
  2. Securely pull the intake grill to open it and access the air filter.
  3. Gently slide the filter upwards and detach it from the casing.
  4. Thoroughly clean the filter by using a vacuum with fresh running water.
  5. Now, securely reattach the intake grill along with the air filter.

Check out this vacuum cleaner on Amazon.

PTAC Unit Smells Musty - Why And What To Do

Since you're really into cleaning mode now, you should also clean its vent screen. This is a must thing to do whenever you clean the filter. Of course, unless you run the PTAC unit with its door closed.

Let's say you need to clean the vent screen. Cleaning the vent's screen includes:

  1. First, you'll see a removal sign in front of the cabinet; remove the cabinet according to the instruction.
  2. Remove all six screws holding the chassis from the wall sleeve using a screwdriver.
  3. Gently slide the chassis from the wall sleeve to properly access the vent screen.
  4. Again, unscrew the three screws holding the vent mess screen from the split panel with your screwdriver.
  5. Ensure you clean the vent screen properly before you put everything along with its six screws and cabinet.

NOTE: The filter cleaning procedure will always come every 30 days or twice a month if the unit runs more often.

Moreover, using a charcoal filter will significantly boost the air quality in your system.

How To Clean A PTACs Base Pan And Condenser Coil

Woman checking air conditioner inside room.

  1. Tightly cover the unit with plastic to prevent water from damaging the main control panel.
  2. Spray the condenser coil and base pan with a biodegradable cleaning agent and rinse it thoroughly.
  3. Clean the drain pan along the coil properly with a low-pressure water hose to remove dirt.
  4. Tilt the unit a little bit to drain the water out from the side of the unit.
  5. Ensure that no excess water is left in the base pan; otherwise, use a dry cloth to wipe the remaining water.
  6. Remove the unit's preventative cover.
  7. Securely reinstall the unit back again into the wall sleeve.
  8. Allow the unit to dry for about 24 hours before turning its power.
    • Once its power is turned ON, conduct a run test to ensure the system's operation is in order.
  9. In the base pan, apply a non-acidic algaecide to prevent the formation of bacteria.
    • Make sure the algaecide is safe for use with wet coils and won't damage the coil.

View this foaming coil cleaner on Amazon.

What Maintenance Does A PTAC Unit Need?

Air conditioner and cleaning work.

Besides cleaning your PTACs filter and vent screen, it has other components that require seasonal maintenance.

Including them in your task will maximize your PTAC system efficiency and prolong its service life.

Always apply the rule of thumb: shut off its power source before you touch anything from the PTAC unit.

Checking The Wall Sleeve

Examine the PTAC wall sleeve sealant to verify that all air and water gaps are not leaking. Avoid over- or under tilting, but tilt it towards outside about 1/4 bubble tilt as you can.

The sleeve needs an appropriate leveling assessment if the appliance has an internal drainage system. All sides should be subject to leveling to ensure that moisture will go to the drain line or kit location.

Checking The PTACs Clearances

Make sure there is enough space around the PTAC unit so that the incoming and discharge air can properly move.

Leave at least 8 inches on all sides between the intake vent from any airflow obstruction to ensure optimal operation.

For this instance, it is best to ensure proper clearances during its installation.

Why Is Regular Maintenance Necessary For PTAC Efficiency?

Owner-operators can identify issues early on and conserve energy by doing routine maintenance. As a result, the appliance can continue to operate with higher energy efficiency.

In the hotel industry, business owners won't lose money on the room while waiting for backup parts. The ESA Cypress Creek hotel ran a test in 2020 to determine the importance of cleaning the coils regularly.

Payment of utility services, concept. Part of an electricity meter, close-up. Selective focus, toned image.

The results show after maintaining regular maintenance. The hotel can save up to 67% on overall yearly energy costs. No matter what kind of cooling or heating system you may have, it requires proactive users to achieve efficiency.

What Is The Difference Between PTAC And Mini-Split Units?

The uses of mini-splits and packaged terminal air conditioners are comparable. They are both unitary systems, meaning they are not intended for use with full floors or structures but rather with discrete portions.

PTACs and mini-splits can be used separately to heat and cool different parts of a building effectively.

Energy efficiency is a mini-split's key benefit advantage, but if it uses ducts, it can cut off energy usage by about 30%.

A mini-split only demands a small entry in the wall for the refrigerant lines connecting the interior and outdoor units, unlike a PTAC, which needs a huge wall opening for the complete unit.

Since there are only refrigerant tubes between indoor and outdoor units, the mini-split's biggest drawback is the lack of air ducting. They can therefore supply cooling and heating but cannot provide ventilation.

A PTAC or PTHP, on the other side, can carry out all three tasks.

What Are The Benefits Of Having A PTAC?

You can select the appropriate heat kind with a PTAC unit, depending on how warm or cool the space is. Here is a list of the benefits of installing a PTAC system in your home or business.

  • Easy to install
  • Quiet performance
  • Enhances the air quality
  • Energy-efficient machine
  • It is a user-friendly appliance
  • Versatile system (works for heating/cooling)

To Finish

Your PTAC unit, like other appliances, needs proper caring and maintenance to keep it functioning with the highest efficiency. Performing a simple yet diligent cleaning will avoid any musty or other foul odor flowing into your system.

Throughout this article, we've talked about how to clean your air filter. You also know how to prevent bacterial build-up in your PTAC system by cleaning its base pan and coils.

We hope that providing this significant knowledge will help you get rid of any bad odor circulating in your indoor space.

Also, we are optimistic that you can now care for and maintain your PTAC unit way better.

Made it to the end? Check out these related posts below:

How To Make A Humidifier Smell Good

Mini Split Smells Like Vinegar -What's Wrong?

Share this article

Leave a Reply

Your email address will not be published. Required fields are marked *