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Converter replacement
I have a 2017 RB with 2 x 6V AGM batteries and solar panels.  My converter recently went bad so I ordered a new one and installed it. I'm plugged into shore power and it started up but the fan on the converter is not running consistently like the old one did.  It runs off and on for a few seconds.  The voltage display is jumping up and down from 12 to 16.  It's a cloudy day here if that matters.  Do you think things will settled down after it's been plugged in a while or should I be doing something different?  It's been plugged in for about 3 hours.
Tammy’s 2017 RB

Re: Converter replacement
Reply #1
UPDATE! Please disregard my questions!  The issue has been resolved.  The voltage variations and the inconsistent fan was bothering me so I started playing around with the button on my solar display board.  I held it down for a few seconds and it seemed to reset everything.  The converter fan started running continuously and the voltage stayed at 13.6. This was just pure luck as I did not find any instructions on this.  Phew! I'm so relieved and hope this helps someone else if they experience the same issue.
Tammy’s 2017 RB

Re: Converter replacement
Reply #2
"...the button on my solar display board."

I know that you are new at the Lazy Daze jargon but I've never heard of a solar display board! Might you be talking about your 'Solar Controller Panel?   ;)
Steve S.
Lazy Bones & Cedar
2004 30'IB (Island Bed)
Yesterday is History, Tomorrow is a Mystery
Live for the day!

Re: Converter replacement
Reply #3
Curious as to what brand of converter you bought to replace your failed Parallax. Mine has failed as well, only puts out 14.6 volts continuously. 
2016 Mid Bath

Re: Converter replacement
Reply #4
Hi Airbusguy;  Your 2016 would likely have a Parallax 8375. Maybe a WFCO 8375 or WFCO 8300 or 8900 series. Complaints are that the fan runs continuously in the 8375 model.. 8355 good for 55 Amps, and 8365 (65 Amps) are common. I haven't kept up with changes.
      An output stuck at 14.6VDC could be the charge voltage. It takes the higher voltage to push power into a 12.6 Vdc lead acid battery. There should be a different lead going to the house wiring at about 13.2 volts.  Solar controller outputs are superimposed on that possibly resulting in higher house voltage levels.
      My old '60's tech Magnetek was worn out, and out dated. I replaced the converter portion with a much better Progressive Dynamics PD4655VL modern supply with a jumper option for Lithium. After about 6 months I exercised that option to convert to two S.O.K. 206 AH batteries. Useable charge of about 400 AH, fit in the same volume (size) as my two Lead acid batteries used, and weighed 26 pounds less. No more water checking.   RonB. 
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB

Re: Converter replacement
Reply #5
My converter is indeed the Parallax 8375. The fan did always run by design of that high amp unit.  I pulled it out a couple years ago and replaced the noisy fan with a nearly silent Zalman computer fan.  I know the Zalman fan does not output enough air to cool the unit at high charge levels, so I added a 2nd fan on a temperature sensor mounted to the heat sink.  This one comes on at around 100 deg F. 
The temp assure board in the unit also quit, I ordered a new one and that was no help. Parallax warranty folks were helpful but I never got that part of it working again.  And then several months later, it sticks at an output of 14.6 volts, never drops down to the 13.2 volts like it used to.
I still have the original Lifeline AGMs, still working fairly well for being 8 years old.  I will replace with Lithium batts soon and need to upgrade the parallax to a lithium capable charger.  I see a boondocker BD-1275MBA that might work and a Powermax PM4 75A. Also the Progressive PD4645V is an option. Or go nuts and go with a 90 amp unit, the PD4590CSV. 
Info is a little weak on installation of these into the Parallax. I would to like to minimize the modification of the heavy wiring inside the unit, avoiding splices in the big DC wires.
2016 Mid Bath

Re: Converter replacement
Reply #6
Hi AirbusGuy; if the converter really is stuck at 14.6 volts, that is perfect for LiFe batteries. The battery management systems inside the batteries will cut off charging when needed. Otherwise 14.6v is what I set the solar controller at. SB3000i again charges as best as it can. The battery controllers do the rest.
 RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB

Re: Converter replacement
Reply #7
The 14.6 is correct, but I wonder what is going haywire inside the unit to be stuck at this voltage. Good point on the BMS protecting the Lithium batteries,  Maybe I will wing it and see how long it lasts. Now to pick up some batteries, so many choices.......
Will Prowse on YouTube has a lot of battery teardown videos and recommendations.
2016 Mid Bath

Re: Converter replacement
Reply #8
After 2 years my money is still on the SOK 206. With the thin steel case. Now with internal heater, bluetooth, UL approval, and lower price. RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB

Re: Converter replacement
Reply #9
Ron is correct that the 14.6V will not harm LFP batteries with a well-designed BMS, but when the BMS shuts off, all circuits in the rig will be running on the converter output. This might stress some things if you stay on shorepower a lot. However, you may find the batteries stay charged fine just on solar, without the converter switched on. I leave ours switched off even on shorepower unless we have a succession of no-solar days. Of course, without shorepower you need to switch the converter on if you need to run the generator to charge up.

If you have a whole-house inverter, the high charge efficiency and low Peukert of the lithiums will allow an adequate solar array to keep up with most uses. A 30-second run of the microwave to heat up a tepid cup of coffee at 140 Amps DC uses just 140/120 = 1.2 Ah from the batteries, quickly replaced. Even a 10 min run for some dinner dish only will use 140/6 = 23Ah.

Steve
2004 FL
2013 Honda Fit

Re: Converter replacement
Reply #10
As Steve said, the 14.6 volts may be a bit high for continued use on the coach appliances. They are pretty much set for 12.9 volts lead acid, but should be good up to 15 volts. The charge portion of the Progressive power supply could be stuck in boost (hopefully Equalize is shut off!). Normally it should be in 'Absorb' a lower voltage. Could there be an adjustment somewhere?   RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB

Re: Converter replacement
Reply #11
When I had it apart, I didn't see any adjustments, just soldered components on a circuit board and a big heat sink. 
2016 Mid Bath