Venting AGM Batteries

[chobe2]

We would like to put two AGM batteries inside our truck camper under the dinette seat. My research is giving me mixed messages about venting so I wrote Lifeline and asked them. This is their reply:
"They should be vented to the outside. They can safely sit under the dinette but they should be in a box and that box should be vented to the outside."

I have read about many who have installed these batteries under the seats with no venting but maybe this is not safe to do?? What do you all think?

[HMS_Beagle]

Venting is a very good idea for flooded cells. If there are regulations, they exist for those, even if the camper is originally delivered with AGM batteries. You never know what will happen in a future replacement. Flooded cells off-gas hydrogen as part of the normal charging process, which is by itself explosive and condenses to acid. AGMs do not off-gas in normal operation, only in extraordinary circumstances, if they do it more than a couple of times they are dead and you are going to be replacing them.

[time2roll]

I understand the venting is in NEC and RVIA requires following NEC.
No I do not have a book and am not an expert. Have stayed at a few Holiday Inn however.

[full_mosey]

rottidawg wrote:

smkettner wrote:
Yes RVIA standards require venting.

If so then why do many camper companies not vent there AGM batteries? Like I said before, FWC and ATC sell a lot of campers and they do not use vents. They are also manufactured in Kalifornia which has a rule/law for everything.

I would also appreciate hearing the answer to this.

Cite the RVIA regulation. 🙂

I debate this not to be for or against venting batteries.

The word 'regulation' implies civil authority. Isn't it true that the RVIA is only a voluntary mfgrs association with standards for certification? Is there a civil penalty involved if an RV does not have the decal?

Further, this box must have two vents; one low in the box and vented outside and below the box and, the second vent high in the box and vented outside higher than the box. This allows the safe(?) exit of both H gas and acid mist.

HTH;
John

[rottidawg]

smkettner wrote:
Yes RVIA standards require venting.

If so then why do many camper companies not vent there AGM batteries? Like I said before, FWC and ATC sell a lot of campers and they do not use vents. They are also manufactured in Kalifornia which has a rule/law for everything.

[time2roll]

Yes RVIA standards require venting. With a quality battery and reliable charging system I would probably skip it but hard to recommend for others to do.

Optima D31T has a vent connection to attach a small tube. Not quite as space efficient but no box may help.

See Google Images "Optima D31T"

[Reddog1]

I will stand by what Lifeline says in their literature/manual. We can do lots of things differently, but it does not make them necessary.

[cewillis]

jimh425 wrote:
For those of you with "sealed" boxes are they airtight?

No, I would not say 'airtight'. Was going to put that in my post, but got lazy. Mine do have rubber gaskets around the lids, but there is some slop where the cables enter the boxes.

[chobe2]

Thank you all. You guys seem to be split down the middle. I guess we'll just have to decide which way to go...hate to make another hole in the camper. Maybe, better safe than sorry.

[free_radical]

AGM s dont need to be vented as they are sealed..

If however one or two cells broke as happened to me it would release gas
when charged..I only noticed this when battery didnt hold charge,,didnt smell anything though..

Btw the battery was made in China..

[HMS_Beagle]

AGMs are commonly installed in boats with no outside venting. Usually there is no way to do it. If your AGMs are venting gas, you are abusing them in some way and they won't be doing it for long!

[jimh406]

For those of you with "sealed" boxes are they airtight?

[cewillis]

I have 4 AGM batteries in my Outfitter, 3 under one seat, 1 under the other, all in sealed boxes without vents. Been there for 9 years now, no problems. Yes -- the same batteries for 9 years.

[pianotuna]

Hi,

Not venting is fine until a cell shorts and hydrogen sulfide gas is produced. It smells to high heaven and is quite poisoness. My AGM's are vented to the great outdoors.

[DWeikert]

My Northstar came with a pair of grp 31 AGMs mounted under the sink area. No sealed compartment vented to the outside. No vent's period. I don't lose any sleep over it.