Why is my swamp cooler not working?

Image of vent temperature and vent cleaner

My struggle with cooling my home

I have a confession to make, I should know more about maintaining my cooler than I do. After all, I work for an air conditioning service company. However, it wasn’t until recently that I realized I had a problem with my own swamp cooler that my husband and I had overlooked for 2 years. Let me start by saying that my husband is quite handy and is comfortable maintaining our swamp cooler for summer and winter. I think he prides himself on not calling a professional unless it is something he feels he can’t handle.

We purchased our new home 2 years ago. Along with our new home came a mastercool swamp cooler.  Our previous home had a standard swamp cooler that was quite effective.  While we were hoping that our new home would have refrigerated air, we fell in love with the house and thought maybe eventually we could convert to refrigerated air.  My husband was confident he could maintain the mastercool without any problems.

Halfway through last summer we felt like the mastercool was not cooling our home effectively.  The temps in our home were high and it never felt cool.  My husband checked the cooler and it seemed to be working properly.  So we made the following excuses to ourselves:

  • Well, we know swamp coolers can only cool to a certain temperature.
  • Well, maybe it’s too humid and the cooler won’t cool as well.
  • Maybe it’s because our bedroom is upstairs and faces south, its the hottest room in the house.

Considering Our Options

All of these are correct and can interfere with cooling effectiveness.  If you’ve experienced issues with your own swamp cooler you may have made these same or similar observations.  At this point we considered converting to refrigerated air, upgrading to a breezair and even considered adding a window unit to our bedroom.  We ultimately decided to hold off on upgrading our system since we were nearing the end of summer.

Swamp Cooler Frustrations again…

So here we are a year later.  My husband started up the cooler with no problems and we felt like our home was cool through the Spring.  However, we became concerned when temperatures started climbing.  Again we started experiencing cooling problems.  This time I asked one of our technicians for help.  We decided to document this process since this is such a common complaint from our customers. We then went out to examine the cooler.  I was surprised to see that while my husband had cleaned the unit, the inside tubing was completely clogged with hard water buildup.  This severely inhibits the amount of water coming through the cooler and doesn’t saturate the pads.  As you can see in the pictures below the pads were only getting wet in spots.  When my husband prepped the cooler in spring he cleared the holes in the water distribution tube but didn’t take it apart completely to clear out any buildup inside the tube.  Once the technician thoroughly cleaned the tubing and ensured that there was no buildup remaining inside, the water flowed correctly.


Now when we started up the cooler and did a second reading the air coming out of the vents was almost 12 degrees cooler than before.  Needless to say, this has made a huge difference in our home.  It is now much more comfortable than it was before. Basically because of this issue we were just blowing hot air into our home.


So my lesson learned, a thorough cleaning will help tremendously. Don’t make the same mistake we did and just make excuses for your cooler.  If you’re experiencing problems with your swamp cooler check to see if your pads are getting wet, if you can of course.  If not, or you don’t feel comfortable getting on your roof to check your cooler, contact a professional to take a look at it.  We’re right in the middle of summer, and these summer rains can interfere with swamp coolers effectiveness.  But if you feel like your cooler is blowing hotter air than normal it may be worth getting an evaluation. Take it from me I wish I had done it sooner.  Plus I now know the value of getting a professional inspection each year to ensure that my cooler is thoroughly cleaned and prepped for summer.

The Value of Professional Swamp Cooler Maintenance