Stumped. Think Converter Is Bad...

[cyauch]

First, let me say that i think i've spent 4 hours searching this site and another popular RV forum site trying to find similar symptoms to mine, but no luck.  However, with info gathered from numerous posts, I feel pretty confident my converter is shot, but hopefully someone with more knowledge can let me know if i'm correct or way off base. 

We own a 2013 Chaparral 330 FBH, and have had it for only a month.  I do have a visit scheduled with the dealer, but that's not until after Christmas, and we have two trips scheduled.  Plus, dealer is 150 miles away, and local shops can't get me in till mid Jan (probably because i didn't buy from them i guess).  So while i would love to have this done under warranty, i may just bite the bullet.  Not sure yet. 

So, here's what's going on.  after 2k mile trip from Gulf Coast to Chicago and back for Thanksgiving, all was good until started making our way home.  After being in it for 5 days, we noticed lights we're dim.  Anything with propane wouldn't work (igniter's wouldn't kick off), Refer Check light was constantly one (propane or Electric).  Didn't matter if we were on shore power or not.  Because it was 24 * F the first night on our way back to Mississippi, we said screw it, pulled the slides in and drove on thru to get home. 

Converter is a WFCO 8930 55 Amp.  Talking to them on the phone, removed batteries from ckt and plugged in shore power.  As lights were turned on, they got dimmer and dimmer.  Never heard fan kick on in converter.  WFCO tech said converted probably shot, especially since it was only reading 4.7 Volts at the distribution panel (red / white wires).  so i opened pass-thru cargo, removed access panels, and loosened converter.  Pulled two 35 A fuses on back to make sure they were ok (they were).  Odd thing though is that when pluging shore power back in, the converter fan kicked on and stayed running.  Speed picked up as more lights were turned on.  Odd.  I told the WFCO tech i'm skeptical about sending this unit back and being charged for the replacement if they couldn't get this thing to not work.  He agreed and said its my call. 

Fast forward to today.  Decided to correct two other shake down cruise items (grey wtr tank #1 valve didn't close 100% and a little air was being sucked into the water pump inlet side of the line.) With those items fixed, i decided to close everything back up underneath as well as remount the converter and close that area up. 

When i re-mounted the converter, the fan kicked off, then would cycle on and off randomly.  I wiggled the ground and both red/white wires, but fan wouldn't come back on.  I turned battery disconnect to OFF and lights went very dim (still plugged into shore power).  Put batteries back online and lights got bright. 

Frustrated, i tapped the top of the converter with a screw driver.  BOOM!  Fan kicked on and lights got a little brighter.  Tapped it again, fan went off.  Tapped floor 3 ft away, nothing.  Tapped floor right next to converter, and it kicked back on again. 

So now I'm thinking something is either loose inside the converter, or maybe a solder joint in there has broke?  Problem is the case is rivited.  I wouldn't mind opening it, but that would be a dead give away to WFCO that someone other than them opened it. 

No matter, i'm firmly sure the converter is shot.  what do you think?

 

[scottydl]

I wish I could think of something else you could try, but that is QUITE an exhaustive list of troubleshooting that you posted!  (Well done by the way.)  Although my appreciation for your post certainly does not fix the problem. 

Is there anyplace near you that sells RV converters?  Just to determine if yours is truly bad, you could buy another one locally and hook it up to see if all your problems are solved.  If so, return that new one to the store (in line with their return policies, not suggesting anything dishonest here) and ship your original to WFCO for a warranty replacement... since it sounds like they made that offer, provided your original is indeed shot by their standards.

Based on everything you've tried and your results, I think that skipping straight to the WFCO replacement may not be a bad idea either.  But the small risk does remain that there is some other ghost in the machine that's NOT the converter, and you'd end up paying for a new one from WFCO unnecessarily.

 

[cyauch]

Thanks for the response!

Yes, there are a couple of RV dealers in my area, small ones, but they do carry some parts.  My plan is to call around tomorrow and see what they have.  With electrical components, not sure if any will take a sold product back.  I'm wondering if there's a way to bench test it.  I wouldn't mind paying the few dollars for that just so i don't get zapped with a c-note bill from WFCO  :-\  I take a some comfort in that the WFCO tech believes the unit is shot, but since its not a hard failure, he admits that's a hard call to make. 

 

[scottydl]

Yeah good point on the electronics angle... return policies are pretty limited.

When my Progressive Dynamics converter died a couple years ago, I called their Tech Support.  The only test they had me "run" was to test the outgoing voltage at the unit itself.  It was really low and the Tech said "anything under 3 volts is toast, send it back."  So I don't think there's much science behind bench testing these units.  Your measurement of 4.7 volts is pretty low too, although only WFCO could tell you what the output cutoff is for their units.

Quite a conundrum indeed.

Some other folks ought to pop in here pretty soon and offer some suggestions.

 

[harris155]

While I see the urgency it getting the converter going but with a 2013 unit you will be negating the warranty offer by Chaparral. In the mean time a cheap auto battery charger could be used to keep the batteries topped up.

 

[Gary RV_Wizard]

Excellent work on the diagnosis.

I suggest that you simply hook an external battery charger to the batteries to get you through the next month and let the dealer handle the converter replacement. A 10 or 20 amp automotive charger will probably tide you over. It will be short of amps during peak load times, but should catch up over night and be ok all day. 10 amps is a bit light for cold weather use, but the price of chargers typically jumps way up if you buy a larger one.

15-20 amp charger would give you more power for peak loads. Home Depot advertises a 20A for $65, but a quality unit is probably going to be $200.
http://www.homedepot.com/buy/rally-manufacturing-20-amp-automatic-battery-charger-7533.html#.UL9Eoqz4J8E

If you decide to buy a higher amp charger, make sure it is rated for a continuous 15-20 amp. Many of the less expensive, consumer-grade units advertised as having 20A capability in fact deliver the higher amps only part time, e.g. 50% duty cycle (they switch on/off repeatedly, so that the average amperage is 10 amps even though the peak output may be 20A).

 

[John From Detroit]

I'm kind of fond of saying that many RVers have a few screws loose.. I am usually speaking of the screws in the breaker box, power inlets, outlets and other conectors and that kind of screw.

In this case... I suspect it is a solder joint.  And finding the bad can be a ton of fun.

Unless you know how to do that kind of thing.. Which by the way I'm doing just now on some battery operated tools.. .. I is likely easier to replace it.

 

[cyauch]

First, thanks to all who have responded and, more importantly, thanks for all the information and feedback.

I was able to speak to Randy at BestConverter this afternoon. Sadly, i thought i would make it home in time to give him a call after reviewing online his suggested replacement converter. I'll have to give him a call tomorrow to make sure i order the correct one. I do remember it was a PD he mentioned. While i don't see a 55A item, i assume he mentioned the 60A.

Still, this evening, bored waiting on wife to get home. So i decided to for sure say this one is shot (which i truly believe it is). So, i monitored the 120v receptacle the Conv is plugged into for an hour by connecting my DVM, then connecting that to my laptop via serial cable. Voltage held steady at ~124V. Next, DVM was connected to the panel breaker and common (which should theoretically should be the same voltage....and it was ). i just wanted to verify the breaker wasn't the problem. So with breaker, recept, and wires checked, 99.9% sure Conv bad.

Still wanting to rule out the .1%, i disconnected battery (which has been isolated via the disconnect switch) red and white wires from DP fuse ckt board, as well as the converter red / white wires. Voltage check on batteries when cutout turned back on was 13.4v. Voltage from converter was 11.2v. When wife jiggled converter, it dropped to 4.7v, then back to 11.2v. Moving other wires, bus bars, or anything else near converter didn't cause it to drop in and out. Only when tapping or moving the converter directly. I know 4v is bad, but even 11.3 or so seems bad with no load?

So i know feel 100% sure the converter is dead (or dying), and feel its more a fire hazard now than anything. I've removed it from the coach. I think i will send it off to WFCO for a replacement, but i think i'm also going to by a better unit to place in the coach, and have the replacement WFCO as a backup in case its ever needed.

Again, thanks to all who've responded and provided feedback! THANKS!

 

[John From Detroit]

When you talk to Randy.. I like the Progressive Dynamics "Wizard" jobs. the 920 plug in model from the sound of it is what you need. 2 wires to connect on one end and plug in the power plug on the other.. Super simple install, Dongle optional but useful.

 

[Gary RV_Wizard]

The WFCO products have good specs, but reliability is sadly lacking. Early life failures are all too common and many reach end of life in only about 3 years. Many RV manufacturers are using them as OEM, so I suspect that WFCO has priced them attractively but achieved that by cutting corners on quality. Another product that gives China a bad quality reputation [in my opinion].

 

[odie1234]

I suggest that you simply hook an external battery charger to the batteries to get you through the next month and let the dealer handle the converter replacement. A 10 or 20 amp automotive charger will probably tide you over.

We had a control board failure in our converter a few years ago. We noticed it early (lights dimming). Hooked a battery charger to the house batteries and used it for three months until we stopped for the winter. Except for having an extra piece of equipment to deal with, and a 110 cord, it worked fine. After getting the board replaced (warranty) everything works well. Good luck.

 

[chrishibbard7]

Wanted to ask for a little more info on this thread, I have a similar problem:

If my house battery is't getting charged, and I want to use a car battery charger temporarily as you suggested: Do I need to disconnect anything from the house battery before I connect the car battery charger?  What's the best way to connect it...directly to the house battery, or at the powerboard/ breakerbox inside my RV?

Here's my problem:
After storing our RV for 1 month, the house battery can't start the generator (won't even turn over anymore) even after plugging into shore power for 2 days.  The battery isn't getting charged:

VDC measured at house battery terminals when plugged into shore power: 11V
VDC measured at house battery terminals when NOT on shore power: 11V
VDC measured at the Neg and Pos "from battery" terminals at breakerbox when plugged into shore power: 13V
VDC measured at the Neg and Pos "from battery" terminals at breakerbox when NOT on shore power: 11V
VDC measured from "Pos Convertor" to Neg "from battery" terminal at breakerbox when plugged into shore power: 13V
VDC measured from "Pos Convertor" to Neg "from battery" terminal at breakerbox when NOT plugged into shore power: 11V

Sounds like the battery is bad, right?  We ran it really low in the fall, after 2 really cold nights w/o shore power.  I want to connect the car battery charger overnight and see... back to the "do I need to disconnect anything" question

I checked the circuit breakers, all the fuses I could find (including 2 hidden behind the breakerbox, under the RV closet) no issues
Here's the data from the sticker in my breakerbox:
Parallax Converter Charger  45AMP Series 7300 Model 7345
Electrical Rating: input 105-130VAC 60HZ 775 watts
Output: 45 amps 16.6VDC
12VDC fuseblock0Max Branch Circuit fuse: 2A
0346 GSM

The WFCO products have good specs, but reliability is sadly lacking. Early life failures are all too common and many reach end of life in only about 3 years. Many RV manufacturers are using them as OEM, so I suspect that WFCO has priced them attractively but achieved that by cutting corners on quality. Another product that gives China a bad quality reputation [in my opinion].

 

[Just Lou]

Since the battery is down to 11vdc, I would disconnect it before attaching the external charger.

Normally, that would not be necessary, but since we really do not know what is wrong with the battery, it would simply be the safest thing to do.

I suspect the battery does have a failing cell and probably will not accept a charge.  At the very least, it is going to require a lengthy reconditioning charge sequence.

 

[scottydl]

And if you disconnect the battery, you might as well remove it and have it load-tested... then you'll know for sure if it's good or bad.  Most auto parts stores will test batteries for free.

 

[chrishibbard7]

Thanks Lou!  After I disconnect the battery,  can I plug my RV back into shore power?  DW is using the RV fridge for overflow holiday foods :0

 

[scottydl]

Thanks Lou!  After I disconnect the battery,  can I plug my RV back into shore power?  DW is using the RV fridge for overflow holiday foods :0

Probably not... many of your "house" items that require 12v to operate (fridge's internal control board is likely included in that group) will need the house battery connected to work.

 

[Lou Schneider]

VDC measured from "Pos Convertor" to Neg "from battery" terminal at breakerbox when plugged into shore power: 13V
VDC measured from "Pos Convertor" to Neg "from battery" terminal at breakerbox when NOT plugged into shore power: 11V

VDC measured at house battery terminals when plugged into shore power: 11V
VDC measured at house battery terminals when NOT on shore power: 11V

That says your converter is trying to charge the battery but there is a bad connection blocking the current from getting in or out of the battery. It only takes a little bit of corrosion in the right place to effectively isolate a battery.

Before you disturb the battery connections, plug in the rig and measure the voltage at the top of the wingnut studs and again on the wire lugs.  You may have to dig in with the probe tips to get good connections.  Any voltage difference between the terminal and the lug means you have a bad connection.

The battery itself may have a problem, but the first thing to do is make sure the connections are clean and tight,  let the converter charge it overnight after you know the connections are good, then measure it's condition.

Don't leave the rig plugged in while you have the battery out.  Some converters will work OK without a battery but others rely on the battery to filter their output, and these can send damaging spikes into your rig's electronics if you run them without a battery.  As long as the refrigerator doors stay closed you can safely turn off the refrigerator for several hours without the contents warming or thawing, especially in cool weather.

 

[chrishibbard7]

Awright, but DW's none too happy about me revoking her extra holiday fridge & freezer! ;D

My house battery is a marine deep-cycle (suspected, but never knew until I disconnected it and took it out of it's plastic casing).  It passed the wimpy load test at Autozone, right before they rushed me outta the shop (bad timing on my part: Xmas Eve!)  I have it charging on a trickle charge in my garage.

Soaked the terminals in bleach, then brushed & sanded, rinsed and re-crimped a little tighter.  Since the battery's still charging, I saw to more sets of terminal ends w/ some corrosion further under my rig.  Took them off (positive side had 4 terminals connected!) cleaned them as well--hopefully these are the only ones between the battery and converter.  All the other terminals I saw were related to the generator.  I plan to re-install the battery tomorrow and  cover all last to terminals w/ Vaseline.

Darn.  Just googled "vaseline conductor".  It isn't.  I shouldn't have added it to the crimped ends after re-crimping.

One last thing--this past fall road trip, I was very disappointed to learn my house battery doesn't charge while we drive (unless the generator's running).  Now that I charge my laptops, phones, cameras, kids' ipod's etc with a small inverter I installed off the alternator, we don't run the generator much.  I found out the hard way after 2 cold nights w/o shore power.  I was stuck w/o any way to start myh generator to charge the house battery.  Had to beg a gas station to let me plug into their outdoor outlet to start the generator, then plug it in "hot".  Any idea how much draw a small converter would be (thinking of jury-rigging it up to my inverter, to charge from the vehicle alternator while driving.  I didn't like being "stuck" w/ no way to start my generator, to charge the battery that starts the generator

 

[gwcowgill]

A failed cell would show a voltage of 10.5 volts or less so I do not think you have a failed cell. It honestly sounds like a very discharged battery. Before getting another battery I would do a initial high amp charge for 60 minutes and then charge overnight at a lower charge rate after which you should find the battery works fine or it will rapidly discharge. If the battery checks good then you are simply not charging it through the convertor. Incidentally a fully charged battery is 2.1 volts per cell.

 

[Charlie 5320]

I just went through this with my coach. Didn't charge while driving. It does take some investigating. I found some wiring diagrams on the internet for battery isolators. I found a 50 amp circuit breaker bad on mine, from one of the solinoids. Replaced it, works great now. $8.00on ebay.