Can Air Conditioner Damage Your Guitar?

Most of us live in houses with air conditioning and we love to keep our air conditioner on all day, especially with hot weather. 

As a guitar player, you have got to make sure that your guitar is kept under the right temperature. 

As guitars are made of wood, glue, and metal, they are susceptible to the outside environment. 

Heat, cold, moisture, and weather variations can play a major part in making alterations to the condition of the guitar.

Air conditioners can damage your guitar by lowering the humidity inside your house. Dry weather can cause neck bow, fret sprout, finish cracking, and even other parts to come off. Also, drastic temperature changes can be harmful to your instrument due to contraction and dilation.

If you aren’t keeping your room severely cold or keeping the air conditioner on for a long time, the impacts, in general, aren’t visible. Most guitars come with some layer of protection for these changes.

But the problem can intensify if you are moving with your guitar and for example, it is in your car and then you go out in the heat. This kind of rapid change can have an adverse impact. 

Can the cold of air conditioning damage your guitar?

The golden rule of the guitar is that if you are comfortable at any temperature, your guitar shouldn’t have any issues. Unless it is severely cold, chances are low that there will be any major damage to your guitar. 

There are two cases you have got to be careful about. Firstly make sure that you don’t suddenly enter your room (if it’s pretty cold) from a much hotter condition outside without the guitar being in the case. The sudden temperature change can be damaging. 

The second case is to make sure your room isn’t very cold for a long stretch. Too much cold makes the air dry and subsequently makes the guitar dry, causing some disturbance in the body, neck, and fretboard.

Can the dryness of air conditioning damage your guitar?

The guitar body requires the air to have a certain humidity. If the relative humidity falls below the comfortable range of 45-55 percent it can crack the guitar body.

The arch in the top shrinks, the neck bows forward, the bridge can seem like it is coming off the body and even the fingerboard can shrink at times, causing what’s called fret sprout. 

If you are playing a dried-out guitar, you are likely going to face a lot of “buzz” noise while playing.

The fingerboard shrink can even cause physical harm if you aren’t careful. As the side metal edges of the frets come out of the neck width so you can even cut yourself while playing. 

Can temperature changes damage your guitar?

Very simple physics teaches us that wood shrinks under cold conditions and expands with heat. 

So, acoustic guitars especially are very susceptible to abrupt changes in temperature. 

The sudden temperature change can cause shrinkage or expansion which can lead to warping and distortion. 

If you are going through winter, suddenly bringing your guitar home from being outside in the cold for a long time can crack the finish on your guitar as well. Although this is mostly true for thinner, more fragile nitro finishes.

If the guitar is exposed to heat after being in the cold for long, it can cause a hairline crack in the finish of your guitar which is known as “checking”. 

In general, the other way round isn’t as bad but if the temperature change is more than 40-60℉, it can lead to some damage.

Ways of preventing guitar damage from AC in the summer

The easiest way to make sure that there is no severe damage by AC is by ensuring that there isn’t a severe temperature change when you suddenly enter the room from outside. 

Making sure that your guitar remains in a case is another way to protect the guitar body. 

If the guitar is in the case then for even a sudden temperature change, the guitar body gets some time to acclimatize to the environment.

You can also use a humidifier to make sure that the humidity level doesn’t go below the 45-55% percent relative humidity. Cold air dries out the guitar. A humidifier can counterbalance that easily. 

What to do if your guitar shows signs of issues from a dry environment

In most cases, if there is a major crack in the neck, top, or bridge, you will have to take it to a luthier to examine and then get the necessary repairs done. 

Neck issues, in general, can be fixed easily with a small truss rod adjustment.

Fretboard shrinkage, and fret sprout, are harder things to deal with and will require the attention of a professional guitar tech.

If your guitar is showing signs of “checking” which is a crack in the hairline of the finish then only a complete refinish would do the job. Ideally, you should go visit a luthier or your guitar shop to get the finish redone.

Guitar, just like anything else made of wood is susceptible to change in temperature. Extreme heat, cold or rapid changes of temperature in general cause the most amount of damage. Make sure you have a hard case when going through rapid changes. 

Also, keep the moisture at an optimal level (45-55% relative humidity) to avoid any hassle. 

Your guitar for the most part will be just fine as long as you are comfortable too. If you have a well-seasoned wood and well-finished guitar, you should be good anyway. 

But it never hurts to be extra cautious.