Not a fan of Maxxfan

[737 Driver]

The control circuit board went out on my aft bathroom fan about a year and a half ago. It was covered under warranty and worked fine for about a year. Then it started chirping and it went out again. Once again I ordered and replaced the circuit board and all was fine for a couple of months. Then on this trip all of a sudden it started beeping and shut down. None of the controls worked and the light that shows activation of the auto fan function based on temperature stayed on. I did get the fan to reset by turning off the salesman switch. I started researching a bit and found numerous of Maxxfan complaints for circuit boards burning up because of “too high voltage “. So I sent of an email to the manufacturer of Maxxfan and received an email back that stated if the voltage is higher than 13.5 volts it will shut down. It was further recommended that I installed a voltage regulator to keep the voltage steady at 12 volts
The battery chargers we have will bump the voltage above the 13.5 volts depending on the battery state at times. During my search regarding this issue one poster received a statement from Maxxfan that they order circuit boards by the “boatloads “. How about designing a circuit board that can at least tolerate what our battery chargers put out? Would anyone know if Entegra installs voltage regulators in the fan circuits on newer models? Perhaps a different fan manufacturer?
It would be interesting to see if this is a widespread issue in the Entegra community.

Safe travels.

-Tor
2017 Entegra Anthem 44B

[Jim_HiTek]

That is not very helpful of Maxx fan at all.

Back in the day when I was designing automotive products, the rule of thumb was to design a product to operate continuously from 1/2 to 2X the battery voltage. So 6 volt to 24 volt for a 12 volt system. And then to have the ability to absorb any 'load dump' from the alternator from 60-100 volts.

Your RV's alternator is designed to output up to 15 volts (13.8 is typical) unless it has a problem, then it could be higher so be sure to check that voltage just after starting the engine.

I would disconnect the Maxx fan, or get a 10 watt 10 ohm resistor and put in series with the power lead to the Maxx while I was working on the problem. Just to reduce the voltage a tad. Might have to adjust the value somewhat. Measuring the current the Maxx air uses and the max voltage that reaches the circuit is the best way to calculate the resistance value.

[757driver]

Originally Posted by 737 Driver

The control circuit board went out on my aft bathroom fan about a year and a half ago. It was covered under warranty and worked fine for about a year. Then it started chirping and it went out again. Once again I ordered and replaced the circuit board and all was fine for a couple of months. Then on this trip all of a sudden it started beeping and shut down. None of the controls worked and the light that shows activation of the auto fan function based on temperature stayed on. I did get the fan to reset by turning off the salesman switch. I started researching a bit and found numerous of Maxxfan complaints for circuit boards burning up because of “too high voltage “. So I sent of an email to the manufacturer of Maxxfan and received an email back that stated if the voltage is higher than 13.5 volts it will shut down. It was further recommended that I installed a voltage regulator to keep the voltage steady at 12 volts
The battery chargers we have will bump the voltage above the 13.5 volts depending on the battery state at times. During my search regarding this issue one poster received a statement from Maxxfan that they order circuit boards by the “boatloads “. How about designing a circuit board that can at least tolerate what our battery chargers put out? Would anyone know if Entegra installs voltage regulators in the fan circuits on newer models? Perhaps a different fan manufacturer?
It would be interesting to see if this is a widespread issue in the Entegra community.

Safe travels.

-Tor
2017 Entegra Anthem 44B

The person at Maxxair that said the fan would shut down above 13.5v does not know what he is talking about. ALL Entegra coaches are at one time or another above 13.5v and this has NOT been a wide spread problem in the Entegra community.

[Jim_HiTek]

Originally Posted by 757driver

The person at Maxxair that said the fan would shut down above 13.5v does not know what he is talking about. ALL Entegra coaches are at one time or another above 13.5v and this has NOT been a wide spread problem in the Entegra community.

I would tend to agree. Don't think anything lower than 15 volts would be acceptable for shut down and would hesitate to believe anything lower then 24 volts would ever cause a shutdown.

[737 Driver]

Originally Posted by Jim_HiTek

I would tend to agree. Don't think anything lower than 15 volts would be acceptable for shut down and would hesitate to believe anything lower then 24 volts would ever cause a shutdown.

I totally agree with you but that is what I was told. If you do a google search on Maxxair issues you will find many similar issues with the Maxxair circuit boards and the same response from the manufacturer. All I know is that I am on my 3 board and still having issues

[Gary.Jones]

The MAXAIR fans on my 2 coaches have never beeped or failed to operate in the time I have owned them (now 4.5 years). I really doubt that is the problem. However, try a voltage dropping resistor in series and see if that solves your problem.

Gary

[voltdoc]

Wow Don that's interesting. It seems irresponsible for a manufacturer that builds a product for mobile "12v" environments to not account for voltage tolerances normally encountered in that environment. It would probably be a matter of a few cents to modify the design to properly handle that.

OTOH in 6 years of Entegra ownership on 2 coaches with Maxair fans we have never had a hiccup. We run our fans constantly as I am a proponent of continuous ventilation.

Must be those Lithium batteries, your megawatts of solar or the Canadian power grid.

Guess I would be more in favor of a voltage buck device to regulate the voltage than a dropping resistor. The fan power draw has a lot of variability so a buck device will keep the voltage steady no matter the draw whereas a resistor will not. There seem to be a lot of inexpensive options around. I don't know the max current draw of the fan but here's one that claims to handle around 2 amps. I'm sure there are many more options.

DEVMO 2PCS LM317 DC-DC Converter Buck Step-Down Circuit Board Module Linear Regulator Adjustable Voltage Regulator Power Supply https://www.amazon.com/dp/B07R5RP2NG..._2EDxDb08TN2ZN

[Gary.Jones]

Rob

That is NOT Don (757Driver) that is having this problem..... the problem is being had by another air plane jockey apparently ---- 737Driver.... named Tor.

Don is agreeing with your diagnosis...dumb design for the sort of environment that the fan tends to be used in.....

Might have the same Lithium and solar problems as Don, but a different character.... ...

Gary

[voltdoc]

Oops thanks Gary, my bad, too many 7x7 drivers on this forum. Sorry Tor and Don but comments still apply. Tor, are you doing frequent "equalizing" cycles? Intentionally or not? That puts 15+ volts on the coach 12v systems.

[Smitty77]

Installed a Maxxfan in our coach 2 1/2 years ago. It is still working, but even after calling and asking for advice on how to work the remote - it's always a mystery of the combination of buttons needed to be pushed to both close the cover, and turn off the fan. Different times, it works different ways. Sometimes I have to walk away, and come back a bit later and try again...

97% + of the time. If I only want to turn off the fan, but leave the cover up and open - I have to first Close the Cover, then hopefully turn off the fan, and then Raise the Cover into the open position. Lots of wear and tear, and poor software to say the least...

I suppose to be more helpful on info sharing, the specific model of Maxxfan should be included - I'm sorry I do not recall it now... It was their top fan when we bought - who knows how it matches what are installed on your coaches...

Best to you all,
Smitty

[cavie]

Boards, boards boards. I love old school. Give me a crank and a pull chain switch any day. Way too much Chinese Hi-tech in today's RV's.

[vito.a]

We have a MaxxAir Maxxfan plus 00-04500K with remote. I installed it a little over 2 years ago in place of the original Fan-Tastic fan. It has always worked well and I like it a lot more than the Fan-Tastic fan. Our 12v system routinely goes over 14 volts as the Magnum MSH-3012 inverter charges the batteries and at least so far it has not been an issue. I am thinking about replacing our other two Fan-Tastic fans with Maxxfans.

[bill2011]

Originally Posted by Smitty77

Installed a Maxxfan in our coach 2 1/2 years ago. It is still working, but even after calling and asking for advice on how to work the remote - it's always a mystery of the combination of buttons needed to be pushed to both close the cover, and turn off the fan. Different times, it works different ways. Sometimes I have to walk away, and come back a bit later and try again...

97% + of the time. If I only want to turn off the fan, but leave the cover up and open - I have to first Close the Cover, then hopefully turn off the fan, and then Raise the Cover into the open position. Lots of wear and tear, and poor software to say the least...

I suppose to be more helpful on info sharing, the specific model of Maxxfan should be included - I'm sorry I do not recall it now... It was their top fan when we bought - who knows how it matches what are installed on your coaches...

Best to you all,
Smitty

Smitty in order to stop fan but leave cover open on mine I push the power button then immediately push the open close button. This results in power off but cover still open. Don't know if that will work for you.

[bill2011]

Originally Posted by 737 Driver

The control circuit board went out on my aft bathroom fan about a year and a half ago. It was covered under warranty and worked fine for about a year. Then it started chirping and it went out again. Once again I ordered and replaced the circuit board and all was fine for a couple of months. Then on this trip all of a sudden it started beeping and shut down. None of the controls worked and the light that shows activation of the auto fan function based on temperature stayed on. I did get the fan to reset by turning off the salesman switch. I started researching a bit and found numerous of Maxxfan complaints for circuit boards burning up because of “too high voltage “. So I sent of an email to the manufacturer of Maxxfan and received an email back that stated if the voltage is higher than 13.5 volts it will shut down. It was further recommended that I installed a voltage regulator to keep the voltage steady at 12 volts
The battery chargers we have will bump the voltage above the 13.5 volts depending on the battery state at times. During my search regarding this issue one poster received a statement from Maxxfan that they order circuit boards by the “boatloads “. How about designing a circuit board that can at least tolerate what our battery chargers put out? Would anyone know if Entegra installs voltage regulators in the fan circuits on newer models? Perhaps a different fan manufacturer?
It would be interesting to see if this is a widespread issue in the Entegra community.

Safe travels.

-Tor
2017 Entegra Anthem 44B

Over the last 9 years with two different Entegra's we have not experienced this problem.