Can a Swamp Cooler Run All Day? What Could Go Wrong?

Last Updated on July 3, 2022

Swamp cooler is a great cooling option for indoors and outdoors. They are simple in operation and highly economical compared to air conditioners. But then one might wonder, why not run it entire day? Can you run a swamp cooler all day long?

You can run swamp cooler entire day only if you are OK with filling it repeatedly and extra rise in relative humidity. If not filled on time, it could cause pump failure, unless you are using continuous fill evaporative cooler that fills automatically. Other side effects of running swamp cooler 24 hours a day are energy wastage and increased maintenance.

Swamp coolers are different in their cooling operation compared to air conditioners. Unlike an AC that requires close room, swamp cooler needs a crossflow of fresh air. Thereby, in case you are not available at home, you wouldn’t make much difference by cooling for extended time using swamp cooler.

So, what to do? Should you run your swamp cooler 24/7? What is the downside? What timings to operate on? How long should you run your cooler? Worry not, I will answer all of your questions. This article covers all you need to know about this topic.

Swamp Cooler Operation Timed on Clock

Why Do You Want to Run a Swamp Cooler All Day?

Before delving deep into problems or benefits of using a swamp cooler entire day, it is a good idea to ask a question.

Why would you want to run your swamp cooler all day long?

Is that for better cooling? Or to save energy? Is it due to inconvenience of turning it on and off?

It all narrows down to two scenarios basically:

Scenario 1: You Are at Home for Most Part of the Day

In case you are home for most part of the day, it is a necessity to run your swamp cooler entire day, to keep it at comfortably low temperatures.

Running swamp cooler entire day will require you to perform earlier maintenance, especially cooler pads, but your ease comes before that. Go for a continuous fill swamp cooler or one with high capacity and you are good to go.

I actually selected a swamp cooler with continuous fill for you. You can click here to check specifications. For a comparatively smaller option, check this one out. You can learn more about swamp cooler sizing in this article I wrote.

The only thing I am worried about though is the moisture that your swamp cooler will give off for long periods of time.

In a hot and dry region, this will usually not be an issue, unless you are restricting fresh air flow. For hot and very humid areas, it is best to just not use swamp cooler, not even for some part of the day.

Recommended time, for which you should run you swamp cooler, varies based on overall relative humidity in your region. For example, is it very dry, moderately dry, moderately humid or very humid where you use your cooler.

The more the humidity in your region, the less it is advised to run your swamp cooler.

The less the humidity, the better the swamp cooler operation, and the more you can run your swamp cooler in a day.

Scenario 2: You Are Not at Home for Most Part of The Day

Before discussing what to do in this scenario, I want to clear a very common misconception.

It is thought that, just like air conditioner, when you run swamp cooler for a longer time, compared to when you turn it on and off, you actually get more efficient operation and better control on cooling and humidity.

Meaning more cooling with less energy. Especially in inverter technology you save a lot of energy by using this approach.

However, it is not the same with swamp coolers.

Unlike ACs, swamp coolers do not operate in close confined spaces. For best and healthy swamp cooler operation, they are required to operate with an adequate crossflow of air with sufficient ventilation.

Spacious Room with Windows

Cooling retention obtained indoors by air conditioner is way more than that of a swamp cooler. Cooling by swamp cooler will sustain for much less time and intensity, compared to an AC that operates in closed confined space.

So why not run your evaporative cooler close to the time of your availability, if all that cooling will be wasted anyways due to open windows?

By the way, about 15 minutes is all it takes to get your cooler pads concentrated and deliver cool humid air at maximum potential. So, considering everything I discussed, if it does not make that much of difference, it is so much better to run it close to the time of your availability.

Thereby, in case you are not at home for most part of the day, running your evaporative cooler entire day, will have somewhat better sustained cooling effect, but in most cases not worth it.

Some Tips About Timings of Swamp Cooler Operation

  • For maximum cooling power and retention, start your swamp cooler first time in the morning and run them for most part of the night.
  • Abstain from running them mid-morning, if you are prone to pollen allergy.
  • Evaporation is maximum when temperature is highest in the day, i.e. close to afternoon. Swamp cooler will operate at maximum potential at this time but not necessarily provide coolest air.
  • Limit hours as much you can, especially if you live in a region that is compatible with swamp cooler but still has relatively high relative humidity.

Why I Do Not Recommended Running Swamp Cooler All Day Long?

There are various reasons why it may not be a good idea, to run your swamp cooler 24 hours a day. I have compiled a list of those demerits for you. Here, have a look:

1. More Refills, More Inconvenience

Swamp cooler uses principle of evaporation for cooling. Thereby, the more you run your swamp cooler, the more water will be used up. As a result, you will have to refill your water tank more often.

Leading factors that affect the number of times you have to refill your cooler include capacity of water tank, size of your swamp cooler and ambient conditions.

Filling Water Tank

Refilling your swamp cooler several times a day can be a constant disruption of your activities. I recommend using an evaporative cooler with big water tank or better go with continuous fill swamp cooler.

I have chosen one for you. You can access specifications by clicking on the link in the section above (in Scenario 1).

Note: You should always keep a check on water levels in continuous fill swamp cooler. Due to faulty float or bent pipe, path of water may be blocked and water tank could go dry, which is detrimental for your swamp cooler.

2. Pump Failure by Dry Pump Run

Previously I talked about how a dry tank could damage your swamp cooler. Let me explain that further.

The most devastating effect this would have will be on the pump. The specific phenomenon in which pump of your cooler runs dry (with no water) is called dry pump run.

The pump used in swamp cooler is centrifugal type and actually uses water as a lubricant (that is right, no oil). When it is deprived of water even for a small duration of time, friction in the internal components causes them to wear and damage the pump.

Friction in Metal Components

This does not take much time, it happens pretty quick, unlike many other components that take much longer time to deteriorate, like cooler pads.

Be Careful, this is something that you should be careful about in continuous fill type cooler, as well as those that require refilling after regular intervals.

You may be sleeping or preoccupied in your activities, meanwhile your swamp cooler could run dry and ruin your pump. Same can happen in continuous fill swamp cooler, in case pipe is bent or float is faulty.

3. Rise in Relative Humidity Indoors

As I told you earlier, swamp cooler uses principle of evaporation to cool. Thereby, it is natural for your cooler to give off moisture.

The rise in humidity indoors is controlled by many factors like size of your cooler, ambient temperature and humidity etc. One of them is the time for which you run your swamp cooler.

Humidity Levels

If you are in a hot and dry region, then this would not be a problem.

However, if you live in a region, where humidity is not high enough to rule out a swamp cooler, but it is not that dry either. That is when this factor becomes important. I have discussed this in detail above in scenario 2.

4. Increased Maintenance

Generally, you should have your swamp cooler checked and maintained every season. However, when you run it 24/7, then it will require early maintenance.

The most often component you would need to change are cooler pads. The more you use them, the quicker they will deteriorate.

However, no doubt they are directly linked with cooling effectiveness of your swamp cooler, this does not necessarily mean they are the most to worry about.

Tools For Maintenance

The most important are mechanical components like motor and pump.  Every mechanical component has a life and number of cycles they can run for. Running them continuously means, their quicker replacement in years to come, or of your swamp cooler.

In maintenance, also give a look to belt connecting blower and motor. It should be adequately tight and adjusted.

Check distribution lines and holes for clogging. Fragments from pads can get stuck in them. This will happen more often depending on the time for which you run your swamp cooler.

For cleaning distribution lines internally, use spider cleaner. I picked one for you. Well actually 2 in 1 packaging. Click here to see specifications.

5. Less Cooling with More Energy

As I mentioned earlier, if you are not at your home for good chunk of the day and swamp cooler is running the entire time, you will lose energy. One might say, it is so that their living space is cooled when they get back home.

However, as I discussed before, the way swamp cooler work is different compared to an air conditioner. Unlike an AC system, that works in confined spaces, swamp cooler requires active flow of air in the room in which they operate.

Thereby, unlike air conditioners, the cooling that swamp coolers generate will not retain for a very long.

If you remain in your home for a small portion of the day only, while the swamp cooler runs for the entire day, it is way more efficient to use it in times of availability.

Anyways, If humidity and refilling is not a problem, you can run it for the whole day. But you only get a little better cooling for a lot of electricity wasted.

Measures To Take If You Decide to Run Swamp Cooler All Day

In case, you run your swamp cooler entire day, depending upon the conditions, I recommend you go through the checklist given below. This will help protect your swamp cooler, your home and your appliances from damage.

Swamp Cooler

1. Size Your Cooler Right

Generally, when it comes to swamp cooler, it is better to go with somewhat larger option. However, as it will be running for the entire day, it is a good idea to decrease moisture as much as possible.

The greater the size of swamp cooler, the more moisture it will add.

Sizing right will reduce humidity without affecting your cooling requirements. Further this will also save you electricity.

2. Maintain Necessary Ventilation

Adequate airflow rate is a necessity for swamp cooler operation. Keep the windows open to develop refreshing crossflow of air. This will allow fresh air in and moist air out and keep humidity in check.

3. Check for Maintenance More Often

More cooler operation means more maintenance.

You will have to go through static components like cooler pads, distribution lines etc. and the mechanically moving components like pump, blower, motor etc. They will need quicker maintenance depending upon their operation.

You can check this with detail in the section above (sub-section: Increased Maintenance)

4. Check for Water Level More Often

Refilling frequency of your swamp cooler depends mainly on time of its operation and size of water tank.

Increasing Water Level

However, even with a very large tank or continuous fill swamp cooler, I still recommend you keep the water level in check.


There can be a leak in the water tank that could lead to dry running of pump. Similarly, in continuous fill swamp cooler a bent water hose or a faulty indicator or float could make your swamp cooler run dry. This will damage pump of your swamp cooler (More Details: Pump Failure by Dry Pump Run).