Fantastic Fans not working

[Jim Gill]

As most of us do, our 2006 Monterey has two Fantastic Fans mounted in the ceiling...one in the water closet and one in the galley. Each of them has an on/off Multiplex wall switch in addition to the on/off switch on the fan itself. Since new, both of these fans have worked well...until last week!!! For reasons I can't explain, both of these fans just quit working at the same time...I can't get either of them to turn on. I have replaced both fuses for each fan...one fuse for each in the water closet above the Multiplex controller and one fuse each in the fan itself. None of them looked like they were blown but I was trying to eliminate any possibility of a bad fuse being the root cause of this problem.

I dropped the galley fan and used a circuit tester to determine if I had a 12v source at the fan...I was unable to locate any electrical power at the fan. I used a wiring diagram from Fantastic to assure I was testing a hot and ground wire and still no power. So, with power coming out of the fuses and no power at the fans, I can only assume some type of wiring glitch between the fuses and the fans.

Does anybody have any experience with a problem like this? If not, any ideas on where to look for the root cause of my fan problems?
Thanks,
Jim
      

[Gerald Farris]

Jim,
Most Fantastic Fans in Beaver coaches have two 12 volt sources. One is wired to open and close the dome and the other one is to the motor control board itself. If yours in wired in this manner, you need to make sure that you have power on both circuits. However, if yours are wired with only one 12 volt source, you probably have bad fan control circuit boards that are located under the fan interior cover. You can call Fantastic Fan technical support, and they will walk you through the troubleshooting process to determine your problem. They are great and easy to work with.

Gerald  

[Keith Moffett Co-Admin]

Jim
If you plan to be at the Redmond rally, they can probably fix it on site for you.  Last Redmond rally they went through both of ours.

Keith

[Dennis Crawford]

Jim,

Make sure the fan thermostat is not interfering if so equippdd.

Dennis

[Edward Buker]

Jim,

I would go look at the multiplex module/board that runs the fan. I have not played with a multiplex system but it would seem like you have no 12V output going to the fan and the fuses are good. It is very unlikely that both fans and boards would fail at once so the controlling circuitry seems like the prime suspect. To test this out you could run an external wire from a 12V source to the wire that is supposed to supply the fan and bypass the normal 12V supply line and see if the fan works. Gerald pointed out that the dome has a separate 12V supply and you could try that also.

Later Ed

[Jerry Carr]

Jim I like Ed's plan try a jumper wire to see if the fans work. I also like the idea of calling Fantastic Fan technical support 1-800-521-0298. They offer a guide for problems also on the web site  http://www.fantasticvent.com/fan-tastic-vent-s-faq.html

the other place you can go is the RV Forum http://www.rvforum.net/SMF_forum/index.php?topic=15163.0

[Keith Oliver]

Jim:

There is another thread with the same question, but I will repeat the likely answer here:


When this happens again, and it will, just go up on the roof and manually lift the lid off of its gasket, then go back down and turn it on again.  It should work again, until the next time tthe polycarbonate cover sticks to the rubber gasket.  The newer models just shut down when the lid sticks closed.  The older ones force the gear to run against the lift arm until something breaks.  The replacement lift arms are cheap due to the large numbers sold.  On the Fantastic Vent web site, the first of the FAQs is this very question.


In my 2007 Dynasty (Patriot Thunder clone) 2 of my 3 fans refused to turn on from the multiplex controls, so I went up on the roof and lifted the lids, tried again and now they all work.