A conversation with an RV tech (long)

[Mike Lewis]

About a month ago, while camping at Letchworth State Park in New York (very nice btw), my trailer furnace failed. It failed all at once: no fan, no nothing, so it wasn't a sail switch problem. I feared that excess voltage had killed the circuit board that controls the furnace. A thread on the forum had warned users about this if they had installed lithium batteries and a charger to handle them, as it would provide too much voltage to 12V appliances such as the furnace, ceiling fan, and water heater. I bought voltage regulators but didn't install them before leaving home. Duh.

I drove out of the park later that day and spotted a van that said "RV Repair" or something similar on its side. I stopped and talked to the guy. I gave him my campsite number and he said he would be by later in the afternoon.

When the guy arrived he looked and said, "Ah, an old Hydro Flame furnace. I've serviced lots of these. Hydro Flame was bought out by Atwood, who in turn was bought out by Dometic."

"I think I killed the circuit board," I said.

He pulled the cover off and confirmed that the circuit board was the problem. "Your voltage is 14.7. That's too high." I was plugged in at the time to shore power. "Your voltage needs to be in the 13 volt range."

"I was afraid of that."

"You guessed right. So you know about this stuff?"

"I know a little," I allowed.

The tech poked around. "These boards are very common and I have some in my van." He replaced the board and had me try the furnace out. It worked. "This circuit board used to cost $80. Now it's $265."

The guy was not a friend of Dometic. He said that they would buy up other companies then stop making parts for their products. He had tried to get a part for a furnace that was very common in RVs and found the part number was no longer available. He asked for the replacement part number was were told there wasn't one. Thousands of RVers have that furnace, he said. "I can still get the parts from China, so far." I don't think the furnace he was referring to is in Escapes but I'm not certain.

I asked him about the Dinosaur circuit boards. "They're great, with a fantastic warranty. But I can't use them for liability reasons. I have to use OEM boards." This made sense. The guy recommended plugging in only to charge my batteries until I could get my voltage regulators installed.

We went outside so he could use the picnic table to write out his bill. The man spotted the Dometic A/C on my roof. "Arrgh! I hate those things. They have too many parts and fail a lot." My A/C has been okay so far, though it is quite noisy.

My final bill including tax was over $500. It was an expensive
educational experience.

[Iowa Dave]

So knowing what you know now, After you installed
The voltage Regulators would you buy a dinosaur board for a backup and do your own install of the dinosaur board?

[HABBERDABBER]

My day is yet to come, and my comeuppance, but the checkbook can dismiss many issues. Pay up, and move on, I guess. There be a price to pay for experience.....yours, and others. This tech you write about sounds like he's been through the hoops.

It's all a racket.....so it seems.

[Mike Lewis]

Originally Posted by Iowa Dave

So knowing what you know now, After you installed
The voltage Regulators would you buy a dinosaur board for a backup and do your own install of the dinosaur board?

Yes, I am considering this. I watched carefully as the guy replaced the circuit board, so I think I can do it if necessary. Or I could buy the Dinosaur board as a backup and have another RV tech install it if my current board fails. That is, if an RV tech is willing to install a board provided by the customer.

[Mike Lewis]

Originally Posted by HABBERDABBER

This tech you write about sounds like he's been through the hoops.

He said he had been in the business for more than thirty years.

[Iowa Dave]

I never mind reading a long post especially when it’s full of good information and well written. Thanks for all the insight and conclusions.
Iowa Dave

[cpaharley2008]

Originally Posted by Iowa Dave

I never mind reading a long post especially when it’s full of good information and well written. Thanks for all the insight and conclusions.
Iowa Dave

What Iowa Dave said....

[wind bear]

Originally Posted by Mike Lewis

The man spotted the Dometic A/C on my roof. "Arrgh! I hate those things. They have too many parts and fail a lot." .

Curious to know what he would recommend!

[fudge_brownie]

Good information and thanks to you and your tech for the insights.

Would this post be a warning to anyone having or considering lithium batteries?

Not having lithium I do not understand what is causing the failure. Is it the batteries themselves being at 14.7 or the fact they need to be charged up to 14.7? With my old flooded six volt interstate batteries I followed their recommended charge rates of 14.6 and my current AGM’s get 14.6 for two hours with a Victron controller.

With lithium is the failed Maxxfan board related?

Sorry for so many questions, just want readers to have a good idea if voltage regulators are necessary and where.

[Mike G]

14.7V, is that because you have added lithium batteries and a higher-voltage charger for them? Are solar panels a factor, too?

[MyronL]

Good stuff there, Mike. Haven't run my furnace in a couple years but now I will test it. Been to Letchworth...how about a picture of the falls?

[cpaharley2008]

Originally Posted by MyronL

Good stuff there, Mike. Haven't run my furnace in a couple years but now I will test it. Been to Letchworth...how about a picture of the falls?

Here you go, Myron......)
https://www.google.com/maps/uv?pb=!1...EUQoip6BAh4EAM

[bborzell]

The most significant part of this post is the statement of the obvious. Dometic buys out competitors and then stops production of replacement parts so that the only option for an owner of one of the bought out brands is to buy new equipment from guess who?

This is not unique to camper components. Guitar manufacturers have been buying up smaller boutique brands and then shelving the brand.

Ironically, I had owned a Tacoma mandolin for several years that eventually had a serious warranty defect. Fender had bought and closed down Tacoma, but they asked me to send them the mandolin. They checked it out and determined that they could not repair it so they offered me credit for the purchase price. I opted for a new Fender Princeton Reverb amp that matched the $1,300 original cost of the mandolin. Dometic could learn from Fender, but they won’t.

[Mike Lewis]

My understanding of this is not 100%, so someone please correct my errors. After installing BattleBorn lithium batteries I read discussions on the Escape Forum that said the trailer's original battery charger was not optimal for charging them, as its voltage output was too low. I replaced the charger board with a Progressive Dynamics charger, which produces 14.7 V. But-- when plugged in to shore power this new charger also sends the higher voltage throughout the trailer. This is what causes the problem with the furnace, water heater, etc.; their circuit boards can't take the higher voltage over a period of time. So new boards or voltage regulators are needed.


When not plugged in to shore power my batteries stay in the 13 volt range. Right now they are at 13.25 volts. The tech I had the conversation with recommended that I stay unplugged until I needed to charge the batteries in order to reduce the time the trailer's components were exposed to excessive voltage. This is what I will do for the remainder of my current trip.

[Mike Lewis]

Originally Posted by MyronL

Good stuff there, Mike. Haven't run my furnace in a couple years but now I will test it. Been to Letchworth...how about a picture of the falls?

My photos of the falls aren't worth writing home about. The Genessee River was low, the leaves hadn't started turning, and unlike Jon V. I'm too lazy to walk down to the base of the falls for photographs. But here's one anyway.

[Vermilye]

Originally Posted by Mike Lewis

My photos of the falls aren't worth writing home about. The Genessee River was low, the leaves hadn't started turning, and unlike Jon V. I'm too lazy to walk down to the base of the falls for photographs. But here's one anyway.

You also missed the prettiest time of year (mid October):
(Upper, Middle & Lower Falls)

[Mike Lewis]

Some clarification: The Progressive Dynamics charger appears to go over 14 volts for the trailer as a whole only after the batteries are fully charged. I have access to shore power at my location and my batteries were at 85%, so I plugged in to see the voltage. It is about 13.5 V with 21-22 amps going into the batteries as they are charging.


When the batteries are fully charged I'll check the voltage again and report it.

[Mike G]

Originally Posted by Vermilye

You also missed the prettiest time of year (mid October):
(Upper, Middle & Lower Falls)

You shouldn't have done that. Now I want to be there!

Nice photos.

[John in Santa Cruz]

I speak mostly from the experience of the specific setup I have, which hasn't fried anything yet.

you can 80-90% charge lithiums with 13.6-13.8V, however, the integral BMS will never enter 'cell balancing' until the voltage is 14.4V. once the cells are rebalanced (doesn't take an hour), you can drop the voltage back to 13.6 or 13.8V and they will be maintained at their 100% level. My Victron SmartSolar 100/30 does this. My PD4655L does not. The PD4655 in Lithium mode is preset to 14.6V which I agree is kinda high.

I leave my PD4655 switched off at the circuit breaker(*) most of the time, and let my 360W solar take care of my battery consumption, as it can generate over 2KWH/day which is 3X my average usage.

(*) I rearranged my breakers, removing the splice that put the fridge(?) on the same breaker as the power converter, so breaker #2 is JUST the converter now.

[Mike Lewis]

Originally Posted by Mike Lewis

When the batteries are fully charged I'll check the voltage again and report it.

The batteries stayed under 14 volts until they were charged to 100%, then the voltage went to 14.25 or something. I unplugged the trailer and the voltage dropped below 14 after a few minutes.