Holes in battery compartment of Fiver

Allworth wrote:
Sorry, cross venting is NOT required in a battery box. Years spent doing safety inspections on heavy equipment speaking here.

Because hydrogen is lighter than air, a top vent is required for confined space installations. the vent must open to "an external surface". Most RV battery boxes (that I have ever seen) are made of an acid resistant ABS material, closed on the bottom and vented on the top, with a flexible hose attached to the top vent and running UP to a vent in the front or side wall of the basement. The explosive hydrogen floats up and out. It doesn't need circulation of outside air.

It certainly wouldn't hurt anything to have a bottom vent, but it is not required.

Not correct and not sure what heavy equipment has to do with RVs or the RVIA. It does no good to have a top vent without a bottom vent as the air remains stagnant. Natural draft ventilation requires air movement and air movement requires a high and a low vent for natural draft. It even applies to UPS rooms, a vent at the roof, and equal size vent at the floor. Boats do not require the bottom vent for obvious reasons, but they are vented at the rim of the lid to atmosphere and require a forced draft arrangement in the engine compartment while underway at speed supplemented by a mechanical ventilation means (fan) while stationary.

An RV battery box located near the electrical gear in an enclosed cabinet has a vent at the top that goes to the exterior via flexible hose, and vent at the bottom remote from the one at the top (opposite end). If the batteries are located in their own compartment open to the ground below, they don't require anything, or they are in a box with ventilated lid to atmosphere to contain any spills. I can't say when it started, why, or whether it is required by RVIA, nor do I care. I'm just explaining to the RP why he has neatly cut 1-1/2" holes in the bottom of his battery cabinet from the factory. The battery lower vent neck fits through those holes.

Lets just say it is stupid not to vent in the bottom:

Battery venting

Sorry, cross venting is NOT required in a battery box. Years spent doing safety inspections on heavy equipment speaking here.

Because hydrogen is lighter than air, a top vent is required for confined space installations. the vent must open to "an external surface". Most RV battery boxes (that I have ever seen) are made of an acid resistant ABS material, closed on the bottom and vented on the top, with a flexible hose attached to the top vent and running UP to a vent in the front or side wall of the basement. The explosive hydrogen floats up and out. It doesn't need circulation of outside air.

It certainly wouldn't hurt anything to have a bottom vent, but it is not required.

luggage wrote:
I recently purchased a 2002 Mountaineer by Montana (Keystone). I have noticed that in the forward compartments i.e. Propane compartments and in the front compartment under the nose (where battery is stored), there are holes in the floor of the unit. These holes are not wear and tear holes but appear to be precut round holes around pipes and other areas. I wondered if they were for venting of battery even though it has its own vent and for the propane tanks. What I would like to do is plug the holes to prevent critters from inviting themselves in during the winter. Anyone have similar holes in their forward basement compartments? Thanks.

I thought that they were air venting and exhaust for those units had the optional generator

I went to a 120AH AGM and got rid of the vents.

Mile High wrote:
Battery box is required to have a top and bottom vent. Airflow requires 2. If you can see the hole, the original battery box is missing. The original box has a vent out the bottom that fits through the hole, and a vent out the top that ties to a flexhose out the front. The battery box is totally enclosed and isolates the battery from the open arcing electric in the front compartment.

Mile High, is that requirement actually mandated? If so, when was it done? I have no real venting in my battery compartment.

Lyle

Battery box is required to have a top and bottom vent. Airflow requires 2. If you can see the hole, the original battery box is missing. The original box has a vent out the bottom that fits through the hole, and a vent out the top that ties to a flexhose out the front. The battery box is totally enclosed and isolates the battery from the open arcing electric in the front compartment.

Top up your battery and fully charge it for a few days to be sure it is fully charged. Most lead acid batteries will survive a winter w/o freezing if charged.
If they are 12V they are easy to lift out and take home for storage, 6V can be very heavy. Once charged disconnect the + and - cables so there is no drain on them at all. Even a propane sniffer will drain a battery fast.

luggage wrote:
thanks for the input. I suspected some of the things mentioned. Since I should not seal the battery compartment, does extreme cold weather have an impact on the battery?

YES.... unless you keep it with water on plates,and Correct trickle charge,it will kill it.

thanks for the input. I suspected some of the things mentioned. Since I should not seal the battery compartment, does extreme cold weather have an impact on the battery?

Propane is heavier than air. It sinks. That is why the bottom of the tank bay is open.

Hydrogen is lighter than air. It rises. That is why there must be a vent in the battery compartment near the ceiling. A vented battery box with a direct hose from the top of the box to the exterior of the compartment is better.