Through-the-Wall A/C Unit FAQs

Frequently Asked Questions

Check out some of the top questions we receive, along with our responses.


What size AC do I need? How many BTUs?
Guide based on normal room insulation, average number of sun exposed windows and two person occupancy.
  1. If heavily shaded, reduce cooling Btus required by 10%
  2. If very sunny, increase cooling Btus required by 10%
  3. Add 500 Btus per person over 2 people
  4. Add 4,000 Btus if the area is a kitchen

BTU Graphic*disclaimer - Room Size by square footage is an approximation. Please contact an HVAC professional for more information. 

Can I control my Friedrich Through-the-Wall A/C using Wi-Fi?
Yes! Friedrich WallMaster, Uni-Fit, Kühl, and Chill Premier models built in 2019 or later, come with wi-fi built into the unit. For more information, check out the FriedrichLink Page with info about all connected devices.
Can I control my Friedrich Through-the-Wall A/C with Amazon Alexa or Google Home?
Yes! Friedrich WallMaster, Uni-Fit, Kühl, and Chill Premier models built in 2019 or later, can be controlled with our FriedrichConnect or FriedrichGo app using a smart device, or voice command through Amazon Alexa or Google Home. For more information, check out the FriedrichLink Page with info about all connected devices.


The plug on the unit does not match the configuration on my wall outlet.

You should have a licensed electrician look at the outlet. It is an indication of not having the correct voltage to operate the unit. Never alter the plug on the unit. Please refer to the installation and operation manual to verify the correct plug style and voltage prior to selecting a unit.

Click here to view all through-the-wall installation and operation manuals found in our Consumer Product Resource Library. 

The through-the-wall product category and manual type have already been selected, so you can search by your specific model type.  

Does my unit sleeve need to be level?
The sleeve should be level side to side but should have a slope from front to back, normally 3/8" is sufficient. See your Installation and Operation Manual for details or consult a licensed HVAC installer for concerns.
My unit sleeve has openings on the side, can any part of these be covered?
These openings should never be covered, they are a way for the unit to breath and work as it is designed to do efficiently.
Does my window or through-the-wall unit come with a plug?
Yes, all standard window and through-the-wall A/C units come with the plug attached to the unit at the factory.
Is the trim ring required for a Uni-fit installation?
No, while the trim ring is included with the product, the trim ring is a decorative cover and not required for installation. 


How do I reset the check filter light on my product?

You can reset your check filter light by pressing the following buttons based on your product line:

Kühl & WallMaster models - press FAN and SPEED buttons at the same time

Chill Premier & Uni-Fit models - press the FILTER button

What does the "MODE" button do on WallMaster or Kühl?
The "MODE" button lets you select the mode of operation on your Kühl or WallMaster AC unit. On Cool only models, the "MODE" button cycles between COOL or FAN ONLY.  On Heat/Cool models, the "MODE" button cycles between AUTO (heat or cool depending on set point), HEAT, COOL, or FAN ONLY. 


How often do I clean the air filter?
For optimal performance, it's best to clean the filters every 2-3 weeks, depending on how frequently it's used. Once you've cleaned the air filter a few times you will get a better idea of how much dirt is collected in the filter and you can adjust the schedule, as needed.


What is the warranty on my WallMaster/Uni-Fit/Kühl/Chill Premier unit?
The Limited Manufacturer's Warranty includes parts and labor covered from any manufacturer defect for the first year from the date of purchase. The 2nd through 5th year of the limited warranty the sealed refrigeration system is still covered from manufacturer defect, and is just required to obtain a servicer's report or diagnosis stating that the unit has an issue related to the refrigerant system.
What do I need for my unit to be covered under warranty?
  1. The unit must be purchased from an authorized Friedrich dealer.
  2. A service report from a certified technician stating the issue is a result of a manufacturer defect.


Why is my air conditioner icing up?
Icing can be caused by a number of factors. Units that have not been cleaned over a long period of time may have coils and fins clogged by dust, dirt or debris. Clogged coils and fins restrict air flow through the unit, which can cause the compressor to work even harder – so hard, that it may reduce the coil temperature below the normal range in an attempt to make up for the lost cooling power from the blocked coils. Another potential cause is running a unit with a very cold set point (i.e. turning the target temperature down very low) on low fan speed for an extended period of time. This can cause excess condensate to build up on the coils, further lowering the temperature of the coil and leading to icing. It may be helpful to ask an authorized warranty servicer to check the unit for you.
Water is draining into my room from my air conditioner. What do I do?
Water leaking into the room is generally caused by either the unit sitting level in the window or the unit needing to be cleaned. Water collects in the front of the unit and then travels to the back where the slinger ring will toss it against the coils in the back and then the water evaporates. If the unit does not have the proper slope from front to back, then the water will leak out the front. Another possibility is dirt or debris clogging the interior of the unit and restricting water from flowing to the back, causing it to leak out the front. Having your unit cleaned will solve this problem. If you feel that neither of these conditions exist then you need to make sure that there is no air leaking in from the outside around the unit anywhere. Leaking air will cause condensation to form on the outside of the unit which will leak into your room. If there are any air leaks you will need to reseal these areas.
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