Question about Mastercool 67680 Evaporative Cooler Air Conditioner

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Question regarding Mastercool Evaporative Cooler

I have a 5500 CFM Mastercool that I installed last year. This is mounted on the roof and ducted into our 1249 sq. ft. house. There is a difuser directing air into 5 seperate rooms and a extension duct feeding the dinningroom, spare bedroom and second bathroom.

For the first two months or so it worked fantastic. It kept our house really cool. After a time the water line broke feeding the float tray. I called the service company that installed the unit since it was under warrantee and they came and repaired the broken line. Since then it never worked as efficient as it did proior to the water line breaking.

I understand the consept of how they are supposed to work i.e. temperature and relative humidity. But it seems that the volumne or should I say CFM has deminsihed in relation to the first two month or so. I have checked everything I know to check and cannot locate the problem. I have installed up-ducts in order to create air exchange to cool down the attic and it helped a little.

I wonder if the service company could have changed the shives (pulleys) without me knowing about it since it has never worked as well as it did before they repaired the water line. I know this sounds far fetched but who knows? I have heard of shaddy repairs just so they can get another service call.

So since I don't have any litterature on what size shives this unit requires. I was wondering if anyone of you could help? Also I was wondering if there are any modifications I can do in order to increase the CFM without blowing the circuit breaker?

I have also heard of the double unit where the air is pre-cooled prior to the actual pad. can anyone enlighten me on this?

Thank You,
Best Regards,


P.S. As of right now we have to run two evaporative coolers in order to keep the house comfortable.

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  •  xxxx
    xxxx May 11, 2010

    Start with making sure the unit is getting enough water after the "repair". The cooler pads must be fully wet to get a good result. When you report back, if possible report the temperaure coming out of the vents, the outdoor temperature and the humidity.



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This is just a slight possibility. You may have inadequate exhaust. Open more windows or doors. For every 1,000 CFM of air delivery 2 sq. ft. of unrestricted air relief is required. Check the water distribution system for insufficient water to the pads. Check the pads to ensure they are not clogged and clean if needed.

Posted on Jun 25, 2009

  • Rosemary Brown
    Rosemary Brown Jun 25, 2009

    Sorry, somehow I missed where you did the up-duct install to cover for exhaust/air exchange.



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