Maxxair Fan - Green Light of Death

Travelin3D

We have a Maxxair 7500K in our 2020 320S and are currently on the road. Last night while trying to adjust the fan with the remote, the green light started blinking and beeping and then went solid green and stopped responding. None of the control buttons would work and I finally used the cutoff switch to cycle the power. That seemed to reset the fan, but turning it on gives the same result. 

Has anyone had this problem? Internet search says it may be a bad circuit board; others say resetting the power will fix it. Called nuCamp but this is not a stock item for them. Any suggestions appreciated. 

Michigan_Mike

From E-trailer.com -

Troubleshooting Flashing Green Light and Beeping from MaxxFan Deluxe

Question:

MA00-07500K Have had unit fitted and working fine for a few months I cannot now get weather cover to close had to do it manually and there is a flashing green light on control panel and a constant beeping What could this be and how can it be fixed please

asked by: Robert L

Expert Reply:

I reached out to my tech contact at MaxxFan about your MaxxFan Deluxe Roof Vent # MA00-07500K and he said the flashing and beeping shows a voltage issue. It is either too high or too low to function correctly so the unit is trying to alert you to the issue.

If you don't have a voltage meter, you can use the Powerbuilt Digital Multimeter # BTMT15 and select the 20 V on the reader in the 10 o'clock position. This will give you the voltage reading going to your fan so you can see if you have a wiring issue or a battery issue.

expert reply by: Jason S

Michigan_Mike

Are you in a wet or humid environment?  Maybe it’s condensation creating the issue? I would check the battery connections and check the battery condition itself to ensure you are getting adequate voltage to power up the fan.  

Sharon_is_SAM

Are you on ac or dc?

Travelin3D

We were overnighting at a Cracker Barrel, so running on DC only and it was pretty humid. Battery was down about half on the KIB meter (not great, I know), so also not an overcharging situation. This morning I cycled the power again and using the controls on the fan it worked normally. I haven’t tried the remote yet - I think the low power from its batteries were part of the problem. I changed them out and will see what happens. 

P.S. I called nuCamp, spoke to Creed and got a callback from Austin which I appreciated especially since troubleshooting a MaxxFan is not in their job descriptions. Nice guys, for sure.

Thanks for everyone’s suggestions.

Sharon_is_SAM

Also, keep in mind that the KIB monitor over estimates battery state of charge, so low battery may have been a part of it.

jimcenname

Nucamp installed the Maxxair 7500 on my 400 last Friday and within a few days I am having the same green light flashing, beeping, not working problem. Have you resolved your issue? If so how? My research indicates the fan has a narrow voltage range and if outside of that range green light/beeping/not working happens. (This thread adds more color but no solution: https://www.rv.net/forum/index.cfm/fuseaction/thread/tid/29935614/gotomsg/29936028.cfm)

Sharon_is_SAM

@jimcenname  - We recently had problems with fuses blowing in the fuse box and in the Alde.  It was proceeded by the MaxxAir fan green light and a clicking sound attributed to the motor attempting to lift the cover.  Austin found a single strand of wire had come loose and was making contact with the fan housing causing an intermittent connection and resulted in too little voltage to operate the fan.  He fixed it and it has been fully operational.  

qhumberd

Travelin3D said:

We were overnighting at a Cracker Barrel, so running on DC only and it was pretty humid. Battery was down about half on the KIB meter (not great, I know), so also not an overcharging situation. This morning I cycled the power again and using the controls on the fan it worked normally. I haven’t tried the remote yet - I think the low power from its batteries were part of the problem. I changed them out and will see what happens. 

P.S. I called nuCamp, spoke to Creed and got a callback from Austin which I appreciated especially since troubleshooting a MaxxFan is not in their job descriptions. Nice guys, for sure.

Thanks for everyone’s suggestions.

We are new to the TAB 400 but found this in the Unofficial nüCamp T@B400 Resource Guide ©2019:

When it comes to the batteries, however, this KIB four-light monitoring system is more dangerous than helpful. Our trailer has a pair of 6-volt Absorbed Glass Matt (AGM) batteries and they can’t be allowed to drop below 50% discharge which per the battery vendor is 12.2 volts. Using the grid above, the KIB monitor would illuminate GOOD reading as 12.2 is between 12.5 and 11.7. By the time the monitor displayed FAIR, the battery would be below 11.7 volts and further use will seriously damage them. Just don’t use this monitor.

My guess would be that if your KIB was at the FAIR level it would trigger a low voltage from the fan as the battery would be less than 11.7 volts...not good.

Travelin3D

Yes, the MaxxFan seems to be sensitive to voltage fluctuations. We also had it happen once spontaneously. What I have found is that if you interrupt all power (battery cut off switch and/or pedestal power if you’re also plugged in) the fan will reset itself. After that, we have mainly used the on/off switch on the unit itself instead of the remote. It seems like the remote can cause conflicting commands which makes the unit go green light - fresh batteries in the remote seem to make a difference. This is all anecdotal so YMMV. This happened while we were on the road and I found it very frustrating trying to get through to MaxxAir by phone or website. I got a better response from Creed and Austin at nuCamp even though they couldn’t really offer any help.

jimcenname

@Sharon_is_SAM: Thank you for the hint of the wire strand. I have not yet opened up the fan to find the wiring. I hope it is accessible. My concern, according to the installation instructions is that the power connection is made prior to inserting the fan unit into the opening in the roof. 

Another thing I noticed when pulling the camper fuse to reset the fan is that upon reinsertion the fuse sparks as I touch it to the fuse receptacle. As far as I know the cabin fan (Maxxair) and the bathroom fan (Fantastic 1450) are the only items on that circuit.

Verna

I just found a link to Maxxair’s website for Maxxair, installation and repair parts (I skimmed through part of it—disclaimer):

https://www.airxcel.com/rv/maxxair/products/fans/maxxfan-deluxe

Travelin3D

You shouldn’t have to pull the fuse to reset the power - just turn the battery cutoff switch off and on, and disconnect from shore power if you happen to be plugged in at the same time. That has worked for me.

jimcenname

@Sharon_is_SAM
Using your hint of short on the Maxxair fan I pulled the cover on the Maxxiar and the wiring install looked great. I then pulled the cover on the Fantastic fan in the bath that Nucamp moved over when they installed the Maxxair, it is on the same circuit as the Maxxiar. There was a pinched hot wire that may have shorted to ground, although the fuse did not fail. The insulation was barely broken as you can see in the photo.  The only peculiarity is that after I fixed the pinched wire the Maxxair failed once and then never again. I've using both fans daily for the last month with no problems. 

Sharon_is_SAM

@jimcenname - are you still getting a spark at the fuse for that circuit?  Maybe want to check for a loose wire at the fuse box.

jimcenname

Update Dec 2020. Recall I had the beeping and green light issue with 2 days of NuCamp installing maxxair 7500 in June 2020. After a lot of pain, which I won't detail here, Maxxair said they'd send me a new circuit board. Updated board is suppose to handle voltage fluctuation better. Supposedly 13.7 volts is the max it can take. Also low voltage can cause the same error but I don't know how low. Anyway, for some mysterious reason a few weeks after the initial problem the new board hadn't shown up and the fan started working normally. I received the new board a few weeks later and chose not to install it since fan was working okay. Fast forward 5 months, 3 weeks ago Maxxair  starting beeping again. I replaced the old board with new one I was saving and it worked, ... for 2 weeks, then started beeping and green light. I called maxxair and tech said my trailer is the problem since I already have the new board, what else could it be?, he says.  I read somewhere that Maxxair sent someone a new motor to solve the same problem. He argued with me about that, then put me on hold then came back and said he'd send me a new motor, in a month or two (Jan or Feb 2021) when they come off back-order. The way it is today is that the fan works at 10% speed but if I turn it up to 50% it starts beeping and green light. I didn't notice that before. Before I never saw a pattern to the error. More in a month or two when the new motor arrives. 

ontheroad

The green light that I had come on, as far as we could figure out, was the temp sensor light... she's tucked away now. I no longer am in charge of the remote..lol.

Travelin3D

In the months since I started this thread, the MaxxAir has mostly worked. However, I only turn it off and on using the controls on the unit; if I try varying the speed, etc., using the remote there’s a good chance it will crap out. Then the fix is to disconnect power (shore and/or battery) briefly and then reconnect. Besides the voltage sensitivity, there also seems to be a “disconnect” between controlling the unit directly or using the remote, as if it’s getting conflicting commands. Disappointing to hear the fixes offered by MaxxAir don’t really work - it’s a great unit otherwise.