Negative Customer Review re: MasterCool Evaporative / Swamp Cooler - And Problems

Latest update: April 23, 2023. Page URL indicates original publication date; meanwhile, times change and the updates continue.

Another summer is on the way. Here is an unfortunately negative product reliability customer review of MasterCool evaporative aka swamp coolers, plus water cooler pump installation and replacement instructions.

It should be noted that water cooler pumps are the least of MasterCool's poor quality control and reliability problems.

The primary purpose of this page is a review of the MasterCool and same-company other brands of evaporative aka swamp coolers. The detailed How-to-Replace-Water-Cooler-Pump segment was included simply because it is such a frequent problem with any and all evaporative swamp coolers. The pump failure is a side issue, it is the other poor quality standards and reliability issues of MasterCool evaporative aka swamp coolers that resulted in the publishing of this negative review. These issues are addressed immediately following the water cooler pump replacement segment.

MasterCool window evaporative cooler.

My personal experience and what this review specifically is referring to is the MasterCool MCP44 Evaporative Cooler. However, the same company that makes MasterCool also makes the Champion and Essick brands of evaporative swamp coolers. If a company makes a poorly manufactured one brand or model, it's a pretty good bet their other brands are of equally poor quality. That's a decision only you can make. At minimum, you definitely want to at least avoid MasterCool.

The first problem was the failed water pump, it lasted a little more than a year. If you are only here for the review, you will find the first paragraph immediately below the cooler pump picture informative; then might as well skip past the numbered list to the next section where things really get interesting. There are also pictures after the review showing what the inside of the MasterCool window evaporative swamp cooler looks like. has over one million page views and is looking for reputable advertisers.

About and How to Replace or Install the MCP44 Series MasterCool Evaporative Water Cooler Pump (instructions will probably work equally well with many other brands and models)

Model ESK5500 Cooler Pump.
There is additional information and pictures of the MasterCool evaporative swamp cooler with the back panel removed following the review.

I acquired the new MasterCool MCP series evaporative swamp cooler unit a few years ago. The water pump lasted a little longer than a year. If you think getting the back panel off the evaporative cooler unit is a major project, just wait until it's time to correctly put the thing back on. There sat the water pump; "Made in China" it duly informed me. Water pumps are the known weak link when it comes to evaporative swamp coolers, the manufacturers know this and so try to make the component fairly easy to replace. Here is the procedure, don't forget to check out the additional pictures and warnings following the main review.

Read the entire list and check out the additional pictures and information a few times before beginning the actual step-by-step pump replacement process. You will then have a pretty good idea of the overall procedure and there will be fewer surprises. In other words, now that you know the hazard points, things will go a lot quicker and easier. In fact, once that back panel is off, the whole procedure will pretty much be intuitive. All the information and pictures makes it sound a lot more complicated than it really is. "Check list" might be a better description than "step-by-step".
  1. Check the electrical info on the replacement water pump and plug into a wall socket for a couple seconds to be sure the new pump works. Note if the new pump already has a protective screen wrapped around the bottom of it.
  2. Unplug the entire unit from the wall socket and turn off the water feed. 
  3. Read the manual. Among other things, it tells you how to remove the back panel and about the water hose you need to disconnect at the top and inside of the unit before you can completely remove the back panel. The additional pictures further down this page have more info.
  4. Drain/siphon water from tray.
  5. Very carefully retrieve the water-protected water pump electrical power cord from the enclosure. Definitely peruse the additional pictures and information further down the page before attempting this, otherwise you might accidentally unplug the cord while it is still in the protected enclosure. If that happens, retrieval of the inside cord could be a major problem. Once the plugin part is reached and extracted, do NOT unplug yet.
  6. Unbolt and/or unscrew the clamps/brackets/etc. that are holding the pump in place.
  7. Pull off the water hose from the pump. There may or may not be a clamp you have to undo first.
  8. Remove the still plugged in old pump and set aside elsewhere on the tray. If no new screen was provided with the new pump, retrieve and clean the filter screen wrapped around the bottom of the old pump.
  9. More than likely, the entire bottom of the unit is filled with peeled paint and other debris. Now is a good time to clean up and get rid of all that. You'll have to move the old pump around while doing this, maybe place it on top of the bracket. Do not unplug it.
  10. Bring out the new pump. It will also be made in China, apparently no other options are  available for this unit. If needed, wrap old screen around new pump as it was on the old pump.
  11. Place the new pump where the old pump originally was.
  12. Make sure the water hose, electrical cord, and bracket(s) are all completely untangled from each other. Review pictures.
  13. Unplug the old pump. Do not let go of the cord coming from inside of the housing, otherwise it might slip back inside; you do not want that to happen. Plug in the new pump. Reinsert electrical cord back into the water-protected location. Don't reattach plastic cap yet.
  14. Reconnect the water hose.
  15. Position everything as you want it to be and attach pump to all the previous bracket and other connection points.
  16. Check tray. Remove all tools, parts, rags, the old pump if it is still laying there, and everything else that doesn't belong.
  17. Turn the water feed back on and confirm the water level rises to the level you wish it to be, give it at least 15 minutes. The higher, the better; but not above the overflow drain height. Adjust float if necessary.
  18. Time for the test. Unhook/Pull away the water hose from the plastic holders on evaporative swamp cooler and make sure the hose is pointed at the ground and well away from the pump and tray. The absolute last thing you want to do is spray either of those pumps with water. Plug evaporative swamp cooler back in the wall socket; turn the pump on for several seconds to check that everything works. Give the fan a couple seconds as well. Turn everything off and re-unplug the cooler.
  19. Push the water hose back into the plastic holders on the swamp cooler. Review pictures and accompanying information. Reattach plastic cap. Give everything one last, good look over.
  20. Time to reinstall the back panel. Brute strength and ingenuity will be required to get that thing setting back on top of the tray. Reconnect the hose at the top. You should be able to get your hand in there; grab the rubber hose; and force it back to the top of the tube. Twist and turn the hose as needed to remove any kinks.
  21. Time for more brute strength, ingenuity, and persistence. You will need to lift the panel about an inch or two above the tray; line it up with the sliders on the sides of the cooler; then shove panel flat against the cooler and pull down, hooking the panel back onto the sliders. Multiple attempts will probably be required. When there are no gaps on the sides and between the tray and panel, it probably means you succeeded. I didn't bother putting the two screws back in, that panel wasn't going anywhere. Recheck the water feed valve is still on.
  22. Plug the unit back in the wall socket; ponder that switch panel for a moment before reaching for it... Check the back panel that all the pads are getting wet. If they are, then it looks like you were successful in reinstalling the back panel correctly. Good luck.
If the water cooler pump had been the only incident, I would not have written this negative review. It is what happened next that pretty much made this review mandatory.

The Day the MasterCool Died...

Everything worked fine for another year or two. Then came that fateful morning...

It was going to be a hot one, temps in the 90's were on the way. I turned the water pump on to soak the pads as usual for five minutes before turning on the fan. The little, green light glowed benignly and the water pump whirred happily.

I then went back and turned on the fan. The fan started up. Then the whole unit suddenly shut down. The fan. The pump. The switch lights. Everything.

I tried again. Everything shut down again. I tried different combinations of turning on the various switches. Self-shutdown every time. I tried using the remote instead. Same results.

I somehow sensed and knew I was already doomed. But I went through the motions and checked the house circuitry and fuse/switch box six ways from Sunday. There were no problems; that cooler was getting uninterrupted power.

I tried messing with the switches again, same results. Then the symptoms changed. At first, the pump and the fan worked fine when each was turned on alone. But whenever I turned the second one on, that's when the whole system would shut down.

Suddenly though, now with each attempt, the switch lights would flicker on and off at random for a few seconds before shutdown occurred. In other words, the lights would start doing a strange, little dance; water pump and blower fan sometimes automatically responding accordingly, sometimes not.

As for checking for loose wire connections, chip creep, or anything else a non-expert might be able to fix; forget it. The switch panel circuit board location was completely inaccessible.

I'm standing there looking at the thing after it had done its little dance and shutting itself off for the 30th time or whatever. Then MasterCool decided it was time to perform the coup de grĂ¢ce to any remaining hopes of repair. It turned itself on. That's right. The unit started itself, all the lights happily flickering back and forth for several seconds with the fan and pump sometimes joining in, and then once again shutting itself down . That control circuit board was not only toast, it was unsafe.

"And that truly is indeed that," thought I. I unplugged the unit for the last time.

I'm sitting at my desk, pondering my next move, when I happened to glance down and notice the back page of the owner's manual (printed in China by the way). It proudly informed me the Essick, Champion, MasterCool family of evaporative swamp coolers are designed, assembled, and serviced in the USA. What they don't mention is all the components were made in China or elsewhere.

As far as I'm concerned, lying by omission is still lying. I put the odds at 99.9% that circuit board switch panel was made in China. Even if it wasn't; it was still a low quality, poorly manufactured component no matter where it was made. And you can bet Champion, Essick, MasterCool brands all use the same supplier(s). That's when I decided to write this review.

Back page of MasterCool manual.

This page is just my opinion. However, evaporative swamp coolers are an expensive proposition. Please do the homework and research before making that final decision. Suddenly having your cooling system malfunction during a hot summer day is not a pleasant experience.

Side note. Here's a video review (opens in new tab or window) from a new buyer of the MasterCool MCP44 series brand. He has both positive and negative things to say about it. He also mentions one very serious flaw. Basically, every insect in the neighborhood will end up inside your home; he'll tell you all about that. I'd wondered where all those moths and gnats were coming from, I even had an indoor mosquito. Now I know.

I would avoid MasterCool evaporative swamp coolers at all costs. And since Essick and Champion are made by the same company with the same poor quality standards, I would seriously try to avoid those as well. Unfortunately, there seems to be some sort of monopoly situation in play. Other brands are hard to find. If anyone can recommend another brand, there are probably a whole lot of people who would very seriously appreciate hearing about it in the comments section.

An Update. A contractor recently told me how to get the front panel off to access the circuit board(s). Basically, you scrape off the plastic at certain points (four, circular, indented, perimeter) and the screws are underneath.

[End of Review. Pictures follow.]

Here Are Some Pictures of What You Will Find When You Remove the Back Panel of the MCP44 Series Evaporative Swamp Cooler

There are two more screw holes at the base. Both were covered with silicon dry gel.
When I removed the gel, no screws were present. Your results may vary.

Once the screws are removed, slide the back panel up off the side slots (remember about those side slots, they'll be your nemesis when reinstalling the panel) and pull panel away from the cooler just a little bit. Do not try to remove the panel yet, the water hose is still attached. Using a flat edge screwdriver will help pry/pull the thing off. Won't be that difficult.

Success. The panel can now be removed. Brute strength and ingenuity will be required.

Welcome to the inside of the MasterCool evaporative swamp cooler.
Note the water hose running along the length of the left side, it is easily detachable and re-attachable to the three plastic holders you see. You'll be doing that when you do your quick test at the end.
The two pumps you see in the tray are the water pump and purge pump. Note the two electrical wires running from the pumps to the square, black hole at the bottom-left of the fan housing.
At lower-right, on the outside, is the water feed.

Where the pump wires go. That black, square aperture in the previous picture was originally covered with the white, square, plastic cover you see. You will need to remove the two screws and plastic cover. These three items are prime candidates for getting lost, so I put them in my empty, front pants pocket.

Now comes the risky business part. You need to fish those wires out of that hole. Do it slowly, carefully, and gently jiggle the wires whenever feeling any resistance. Pulling the wires too hard will unplug them while they are still inside the housing. You do not want that to happen.

You will eventually end up with the two plugs on the outside. Keeping in mind the warning in the first set of instructions, pull out the old cooler pump plug and plug in the new one at the appropriate time and as described.
Reinsert the wires back into the housing; and adjust everything the way you want it to be. Then finally put the plastic cover and two screws back on the electrical access aperture.

Everything reattached and ready to go. Time to do the test as described in the first segment.

After the test, refasten the hose back into the plastic holders. Check entire length for kinks.

A side note picture of the floater, controlling the water level in the tray. Slightly bending the floater rod up or down will change the water level accordingly.

A side note, example picture close up of how the water feed and valve might be connected to the water supply. Configurations vary.

© On this particular article, images are copyrighted by

- End of Article -

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  1. Has any one has lost a animal. Our was dripping water and our dogs were drinking it. We have lost 2 dogs in one day. My concern is what is in this cooler that is making my dogs dying.

  2. Sorry to hear about your animals. Keep in mind that as water evaporates from a swamp cooler, it is going to leave the solids behind. As the more water is used the more concentrated these dissolved solids will become. Your dogs probably died of too much arsenic, barium, chromium, iron, etc. You need to check your local water quality for specifics. To everyone everywhere, do not drink water from or let animals drink water from a swamp cooler nor should you use the water in a vegetable garden.

  3. How do I stop the bugs from coming in from the cooler

    1. I wrapped mine in a screen netting and have no issues now super simple fix and very cheap

  4. Hey. Has anyone had a problem with having two of the Mastercool Swamp coolers turning on and off the other one. Even without controler.
    Bought in different years and Even States. Also in two different Buils.
    Now even Neighbors that also have one might be turning mine off when they turned theres of.
    Only thought is on same frequency??

  5. I have a good one. My circuit board kinked out after about a year. I watched a video about a guy that put a thermostat on it. Did that worked great for another season. Just cleaned the pads and now my motor changed direction after running 5 minutes. Don’t know if I got the motor wet but will let rest for a day or so and try again. Don’t know what causes a motor to change direction.

  6. Is there water supposed to be dripping out from the bottom weep hole time on the mastercool

    1. You may have to tighten your weep hole drain nut or replace the gasket around it. Or it could be as simple as adjusting your float level it may be overfilling and doing what it's designed to do which is drip out

  7. This comment has been removed by a blog administrator.

  8. Yep! My original pump lasted for about 1 year. Replaced it with same model--it lasted about 6 weeks! Replaced pump again, but different company this time. So far 1 week and no issues with the pump. In the meantime, when the fan is on high or medium it turns off after a few minutes and restarts again after a couple of minutes. So, I have to leave it on the low setting all the time. Have never been able to get the back cover on properly since installing it! Other than all that, yeah it keeps the house cool, but I am looking at replacing it with a Carrier!

  9. After a steadfast warrior squirrel cage model finally gave up the ghost after my dad tinkered the engine and we ordered pads that just didn't fit, we bought the master school. It wasn't ever a piece of cake to install for him in the hole vacated by the old unit. It does take up a lot less space though. The first problems were as you stated, the cover is really really hard to get on and off. We chuckled at your description. He even has an elaborate rigging with it to get it right into those slots. Every year when the pads needed to be changed we tremble. The float was really wacky a few times and needed to be messed with too.
    The principle is good because you can direct the air where you want it. Here is one thing you might wish to consider, if a neighbor smokes, has a BBQ or there are forest fires, you can't use it. And in our heat wave this year, the poor thing is trying is hardest to keep it about t wenty degrees cooler than the outside temp but that's 115! Inside is ninety. I'm sad that it's not working well. The old kind from Sears were very cool. You had to get up and turn it down. I have lived in many climates and gone without anything in Europe so i don't expect miracles but it's an expensive, hard to install and maintain device. The bills aren't bad though!

  10. Have replaced the electric fan motor three time in 6 years. Motor costs about $200. They last two years, then windings burn out. The motors are open in the back facing the cooling pads. The moisture can get into the windings as air is drawn in. This motor should be a waterproofed motor and it isn’t. So any money saved from s lost replacing the motor which in itself, is a major job. This is a very poorly designed side Mount and the motor is not designed to work in a highly wet environment. But, Yes, it’s made in China!

    1. My second one, Total JUNK!! Customer service is a clown school, Tina is the ringleader. Liers the hole lot of them.


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