ON a NEW WFCO 8955, at what voltage should

MNtundraRet wrote:
We use our motohome an average of a hundred days each year.

Boondock or hook-ups? There is a distinct difference in terms of battery life.... and other things that don't pertain to this thread.

We use our motohome an average of a hundred days each year.

Skunk Works... now we are talking think pot!!

We boondock 3-5 weeks a year, total, and it is why we have $$ batteries and ditched the WFCO.

Yep. Three week vacations heavy-cycle boondocking for seven years and the battery owner believes he has received excellent service meaning excellent cycle life are out of his RV batteries. Ninety-eight cycles. The same battery with ideal float voltage may last 12-years.

Now, does a light bulb pop on for you? It should have. Something does not add up. I discussed this at length with Bob Besch owner of a smart charger manufacturing company around thirty years ago. The answer should be obvious to techhies. Let's skip the question and dive right inti the answer. This puzzled the PhD's at Lockheed Skunk Works so don't feel bad id the answer does not dawn upon you. HINT It has something to do with the way batteries are charged.

MEXICOWANDERER wrote:
Fourteen times seven.

98?

Sitting on the sofa and eating popcorn is not a workout. A Twenty One Day vacation. Boondocking. Seven years. Daily 50% DOD. One full cycle. Fourteen times seven. Do the math. Do you boondock 3 weeks a year?

Where did this notion of cold weather being tough on a battery come from? A battery is a pile of lead and plastic - not a poodle. It adores -40C as long as it is charged. A battery that hibernates in Arctic clime will far outlive another that spends winters at 30C or even 0C.

Acid does things for a living - eating plates is one of them. Ice cold acid is almost inert to human flesh. Stick yoir finger in 70C electrolyte and you won't have a finger left.

I sort of gave up and punted on my 9855. I found the voltage pot (I think VR1) and cranked it up to +13.9 volts. Get a little better charge rate and I disconnect the power after a day or so as to not boil the batteries. I was only able to see "boost" maybe 3-4 times ever even after running very large wire (about #2.)

[, quote=jrnymn7]"The first pair of T 105's lasted over 10 years."

How many cycles, and how deep?

If you read by past posts you would know my MH sits through Minnesota winters from late October until late March or middle April depending how long winter lasted.

There is no shore power when MH is stored or during camping season. The batteries are maintained by a 9 watt solar panel. One for house and one for chassis battery. During camping season I get by with 2 or 3 hours of using generator each day.

I get an electric site the last day camping to allow full charging for batteries. It should be very obvious to anyone that this regimen has not hurt the battery life.

My WhiffCo makes an excellent 55-amp 13.6 volt FIXED power supply. For floating I rigged up a pair of $2.95 power bricks (paralleled) and two eBay voltage buckers @ $6.00 ea. Takes me a whole ten seconds to re-adjust voltage for temps twice a year.

I like journeyman's answer. Separates the wheat from the chaff.

I got my WFCO into boost by connecting a 50 amp battery tester to it directly , along with the other normal loads, then turning on the power....this was in my old TT, not my current unit.