Upgrade to lithium batteries blows circuit boards....?

[John E Davies]

I have both a water heater and a furnace made by Suburban, and they warn in the manuals about over-voltage damaging the control board. The Progressive Dynamics lithium charger setting is 14.6 volts.

I have been finishing my lithium battery upgrade and wiring changes including a battery cutoff switch. Yesterday I turned on power using the switch and my furnace fan started running, no ignition sparking, the thermostat was on OFF I had to pull the furnace fuse to shut it down. The converter was turned off and the solar was not supplying any power, but I guess the spike from the switch killed the board...? More testing to follow.

Can anyone comment on better replacement boards? Dinosaur makes ones that are claimed to be more robust and to also have onboard voltage regulators, which would help with controlling spikes. 

https://www.amazon.com/Dinosaur-Electronics-FAN50PLUS-Universal-Igniter/dp/B009XU7H8Q/ref=sr_1_3?dchild=1&keywords=suburban+NT-12S+control+board+dinosaur&qid=1611762865&sr=8-3

“The FAN 50 Plus Pins is designed to replace the new Suburban® and Atwood® / HydroFlame® Fan Control boards as well as maintain backward compatibility with the Fan 50 Plus, and UIB Fan Control boards which have been available since 1994. This board can also be used to upgrade older furnaces to add the Fan Control feature.”

My water heater board already failed once, I am thinking about replacing it and the furnace board to reduce the chance of future melt downs. Comments on the Dinosaur or other manufacturers?

Does anyone know if Oliver has made changes to their appliance choices to reduce the possibility of board failure with the new Lithium Package?

Thanks,

John Davies

Spokane WA

Edited January 27, 2021 by John E Davies

[Overland]

14.6 seems a little high. 14.4 is the typical bulk voltage. Can the PD charger be set lower?

FWIW, I’ve had no problems with the Suburban and a 14.4 volt setting. 

Edited January 27, 2021 by Overland

[John E Davies]

19 minutes ago, Overland said:

14.6 seems a little high. 14.4 is the typical bulk voltage. Can the PD charger be set lower?

FWIW, I’ve had no problems with the Suburban and a 14.4 volt setting. 

Overland, the output voltage of my PD4045 lithium section is not user adjustable, I found this statement:

"Output voltage can be FACTORY ADJUSTED to meet OEM requirements for various lithium ion battery chemistries and Voltages. Standard “L” Series voltages are set for 14.6- Volts to meet requirements for lithium iron phosphate batteries. Other chemistries may require different voltages."

I suppose I could ask if the factory can "turn it down", but I think that is  probably a band aid fix for weak appliance boards that might fail anyway... I can't see one or two tenths of a volt making a lot of difference, the bigger spikes seem to be the issue. When my board (maybe?) went, the batteries were at less than 13.5 volts, no charging was taking place.

Thanks,

John Davies

Spokane WA

Edited January 27, 2021 by John E Davies

[Overland]

It's a shame that you can't adjust it.  

Aren't you thinking about using Victron batteries?  They recommend a 14.2 v charge.

[John E Davies]

I was going to use Victrons, I ended up with Battle Borns.

John Davies

Spokane WA

[mjrendon]

I swapped out the original fridge board with a Dinosaur, but that was for a Dometic board failure unrelated to higher Li charging voltages (was using 4xAGMs then).  I am happy with the Dinosaur board's performance so far (1+ year) with Li (Battleborn) since October. 

I would imagine that the solar charger outputs are over 14.2v at times as well???

[mountainoliver]

When I changed out my lead acid batteries with three Battle Born batteries a few months ago, I added a voltage regulator (shown below) to the Maxxfan and bath fan circuit for that very reason. The Maxxfan control board is not known for over voltage reliability. But I have not had any trouble with the other control boards. Actually the only one that is stock is the furnace board. I replaced the water heater board with a Dinosaur board a couple years ago and  the compressor fridge can handle 12-24 volts DC or 110-220volts (50-60 HZ) AC. I think that relatively inexpensive voltage regulators are available that could handle the furnace and would be much less expensive than a new control board, but not sure?
 

[Mike and Carol]

Like @mountainoliver, we installed the same voltage regulator for the two ceiling fans (since he was helping me!).  I also installed a battery cutoff switch and have only turned it on/off a few times, mainly for testing, with no issues.  It might not be a bad idea to use one for the furnace, too.  They aren’t very expensive.  Mike

 

[mjrendon]

48 minutes ago, Mike and Carol said:

Like @mountainoliver, we installed the same voltage regulator for the two ceiling fans (since he was helping me!).  

Do you carry a spare or would you bypass in event of a failure? 

Mike

[John E Davies]

I would be interested to see a wiring diagram, did you just dig around in the big wire bundle below the fuses to find the fan positive wire, and splice into it there? or did you go directly into the fuse panel somehow? Use a fuse tap?

Got a link to that regulator or must I start searching?😬

If my furnace board is fried, I think it would make sense to protect the replacement from spikes and over voltage. Is the DC output of this device pretty stable?

Thanks.

John Davies

Spokane WA

[Mike and Carol]

2 minutes ago, mjrendon said:

Do you carry a spare or would you bypass in event of a failure? 

Mike

We just finished the installation and we won’t be camping until next week.  I don’t have a spare right now, so if this one fails while we’re out I‘ll just bypass.  It probably wouldn’t hurt to get a spare.  Mike

[Mike and Carol]

7 minutes ago, John E Davies said:

I would be interested to see a wiring diagram, did you just dig around in the big wire bundle below the fuses to find the fan positive wire, and splice into it there? or did you go directly into the fuse panel somehow? Use a fuse tap?

Got a link to that regulator or must I start searching?😬

 

We went behind the fuse panel and started testing wires until we found the fans.  Then, we cut it and inserted the voltage regulator.

https://www.amazon.com/gp/product/B07WFMKMV9/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1

 

[John E Davies]

never mind

 

Edited January 27, 2021 by John E Davies

[mossemi]

Last August my MaxxFan started running at various speeds.  It would start out running fine and then slow down after several hours.  MaxxFan support help me conduct some testing and one of the things they noticed was the high voltage on the fan circuit.  I installed a similar or same voltage regulator when I replaced the motor in September.  I placed my voltage regulator in the attic after the fan breaker.  And of course this happened after I installed the Battle Born batteries and the PDI lithium charger. 
It kinda like an 18 year old rebuilding a perfectly good motor to go faster and the rear end or transmission fails under the strain.  And I think it reinforces my appreciation for the products Oliver Travel Trailers produce.  When I as an owner decides to change any portion of the product they engineered and built, I can expect it to change something I didn’t anticipate.

I think the best we can do is to continue to share our experiments, learn from our failures and celebrate our improvements.

Mossey

Edited January 27, 2021 by mossemi

[mossemi]

13 minutes ago, John E Davies said:

Thanks for the link, I am not sure I like that it limits to 12 volts, do you know if there is one that is either user adjustable, or has a 14 volt output?

Amazon has lots of choices in fixed and adjustable voltage regulators if I remember correctly.

Mossey

[mountainoliver]

John, I do carry a spare. Mike’s install is a little different than mine or probably yours. The older Oliver trailers didn’t have a separate breaker panel in the attic so we just tested the wire bundle (all black) coming out of the power distribution center until we found the one feeding the fans. Both fans are fed by one source. My trailer has the breaker panel in the attic with one marked blower (marine breaker assembly). I attached the regulator to that breaker and it was hidden behind the side panel. I purchased the regulator from Amazon (look up DC voltage regulator) and the manufacturer is Drok but there are others as well. You see these everywhere like on riding lawnmowers and golf carts. Just make sure you find one rated sufficiently for the intended load. 

[Overland]

I have to ask if this isn't a purely theoretical problem.  Is anyone aware of electrical equipment actually being damaged by lithium charge settings?  I've never heard of it until now.  I mean, my truck alternator bulk charges at 14.8, and I assume that's the same across all of Ford's lineup, meaning all those transit van conversions would be subject to this issue.  

My Maxx Fan has had issues as well, but the common denominator was that it's happened after being open in a light rain or snow (once plugged in, once not).  I'm more apt to assume that they just have sketchy quality electronics and that one cause for failure is as good as the next.  

Edited January 28, 2021 by Overland

[ADKCamper]

Ugh! In the beginning... the lead-acid battery *was* the voltage regulator. Now that modern battery technology has become somewhat independent of the traditionally accepted range of the nominal 12VDC we are used to, perhaps its time to suggest a design improvement... to include a "whole house" DC voltage regulator (or maybe just a voltage limiter) which feeds a master 12V "loads busbar", and connect all of the charging sources on the "battery side" of the new DC voltage regulator (i.e. to a "charging busbar").

Not sure where to find an affordable/efficient one with a capacity for maybe 100A (?) that doesn't generate too much heat and can be mounted in the already limited mechanical spaces available.

[mossemi]

2 hours ago, Overland said:

I have to ask if this isn't a purely theoretical problem.  Is anyone aware of electrical equipment actually being damaged by lithium charge settings?  I've never heard of it until now.

The fan problem I ran into was with the fan in auto mode and running at 80%.  I noticed the fan running slower than I thought it should be, so I ignored it.  And then I noticed it again and again, so now it was on "my when I get around to it list". 
I can honestly say that my fan voltage problem was not theoretical, but maybe it was a coincidence.  And I can’t say it is a lithium charge setting either.  What I can say is that I didn’t have a fan problem before replacing my PDI DC charger with the lithium charger and I did have the problem a couple of months later.  I will also confess that I did not reinstall the original PDI charger and re-conduct the voltage test I did for PDI's technical support team.  I will say that I am not very good at design or theory, but I am pretty good at fixing things that are broken.  So once I have fixed something, I move on.  And a voltage regulator fixed my problem.  I don’t need to know why it was broken, it’s good enough for me that it isn’t anymore.  I didn’t associate the PDI charger and my fan issue until JD created this post.  And then Mike and mountianoliver the voltage regulator to the conversation.  And I said "duh".
I am plugged into a 120 AC circuit at home 24/7 so my battery cutoff switch is usually in the off position.  So my running 12v supply is the PDI charger.  Which is making some weird humming sounds these days, but that is a different subject or maybe not.

And now that I have made a long story longer,

Mossey

Below is part of the email conversation I had with PDI, with the voltage readings I took at the output of the control board to the fan motor.

From: Mike Mossey

Sent: Tuesday, September 15, 2020 9:44 AM

To: RVP Support <rvpsupport@airxcel.com>

Subject: Re: New form entry is submitted -

 9-14-2020

Time          Voltage at the 2 pin connector to the motor

2:20 PM     13.8

3:00            13.6

4:10             13.3

5:10             13.2

6:10             13.5

7:10             13.3

8:10             13.3

 

9-15-2020

7:20 AM      14.2

8:30             14.1  fan seems to be running slower

10:30           14.1

 

RVP Support <rvpsupport@airxcel.com>    Tue, Sep 15, 2020 at 11:41 AM

To: Mike Mossey

Anytime the voltage exceeds the 13.6 threshold it can trigger the unit to shut down or do things it is not designed to do.

The voltage is above that a lot of the time.   Can we get a voltage regulator inline to keep it around 12.8?

 

Mike Dickey

Technical Assistance Coordinator

RV PRODUCTS, a division of Airxcel, Inc.

3050 North St. Francis

Wichita, KS, 67219

Office:   316.832.4357

Fax:   316.832.3417

www.airxcel.com

Edited January 28, 2021 by mossemi

[mjrendon]

I know the alternator output was mentioned before. The fan may not be running when the alternator is active.

Oliver systems with solar likely see these voltages daily for extended periods.

ZAMP charge controller Absorption charging voltages at 25℃ from manual

--LTO type battery 14.0 +/-0.2 VDC -

-Gel type battery 14.1 +/-0.2 VDC

--LiFePO4 battery 14.4 +/-0.2 VDC

--AGM type battery (default setting) 14.4 +/-0.2 VDC

--WET type battery 14.7 +/-0.2 VDC

Edited January 28, 2021 by mjrendon

[mjrendon]

Why do RV appliance suppliers build systems that can not tolerate voltages greater than 13.6V?

Options other than installing a regulator on the fans might include placing a diode (or two) in series with the fans. Most diodes have a forward drop of ~0.7V per diode.  This would be much less expensive and likely more reliable than the regulators. However the voltage drop from the diode(s) would also occur when the battery was in a low state.

[Overland]

39 minutes ago, mossemi said:

Anytime the voltage exceeds the 13.6 threshold it can trigger the unit to shut down or do things it is not designed to do.

Hmm. AGM charging profiles are 14.4 as well, but MaxxFan designs a unit specifically for trailers that shuts down or goes kaput when you hit 13.6?  Something doesn’t smell right there.

Like I said, I’m more likely to think that their problem is cheap electronics and that voltage is a convenient excuse, particularly if every charger on the market exceeds their limit. 

Edited January 28, 2021 by Overland

[mossemi]

So I will ask this question:  Do you think most MaxxFan failures are water/moisture related or is it an electrical supply issue?

I know from the reading I have done on RV forums, most of the blame is placed on moisture.  And as far as I know, MaxxFan has done nothing to change people’s opinion on that theory.

A true test of the voltage question will be when new fans are installed with a voltage regulator from the start.  And we will see where the data on fan failures lead our thoughts.

By the way, within my support email chain, MaxxFan stated that the fan bearing break in procedure was to run the fan at 100% for 24 hours when the motor is placed into service.  How many of us did that?  I did with my new motor, but I didn’t with the original.  My OTT was used so I really don’t know if it was broken in properly or not.

Mossey

[Overland]

In my case, I think it’s safe to say moisture.  The first of my failures happened after a light rain with the fan open but not on.  In that case, the keypad stopped working, though the remote worked fine. It required a new circuit board to fix. The second was just after a light snow, again with the fan open and on low.  That was again a keypad problem but this time the up arrow would activate on its own, revving the fan to high and even turning the fan on after I turned it off. In that case, leaving the breaker off for a day and finding some sun allowed the moisture to evaporate and it’s worked fine since. 

So it’s possible of course that voltage could be a problem but I’ve yet to experience it. We rarely run our fan on anything but low, just to keep a little airflow going and to pull out the moisture, so we probably haven’t stressed the fan motor much.

That’s the first I’ve heard of a break in period, and I doubt that ours has seen 24 hours on high in total since we got the trailer. Does the manual mention that? Do I have a manual?  Do I need to read a manual for a ... fan?

Edited January 28, 2021 by Overland

[mossemi]

I have never seen or looked for the 24 hour break-in instructions in print on paper or a soft copy.  It was a comment made while discussing the intermittent problem I was experiencing.

Mossey