battery box venting

System

I'm in the process of building my battery box and wondering if anyone has any thoughts as to tying the vent from the box into the bathroom vent. I'm building the box in the attic and the bathroom vent is right there so this would save me from making a longer run and putting another whole in the exterior wall. Just wondering if theres any issues with the hydrogen gases mixing with the methane. thanks again for your advice. shane

mike95490

Re: battery box venting

cdncam wrote: »

I'm in the process of building my battery box and wondering if anyone has any thoughts as to tying the vent from the box into the bathroom vent. I'm building the box in the attic and the bathroom vent is right there so this would save me from making a longer run and putting another whole in the exterior wall. Just wondering if theres any issues with the hydrogen gases mixing with the methane. thanks again for your advice. shane

You have your waste water line that needs vent to roof

You have a blower fan in the bathroom that blows shower steam and #2 fumes out roof/wall.

I would NOT mix my battery hydrogen/oxygen vent with either of those. There is some company that makes an inline sealed vent motor for battery vents.

I'd use that, or a plain ABS line, marked so that if a plumber goes on the roof to send a metal snake/roto-rooter down the vent to clear a clog, he doesn't find your battery box ! Whoo Hoo !!! how did that melt ??
(the week you are out of town, and the wife plugs the drain up)

Are you placing your heavy battery box in your attic ? I think that's a bad move. Have you considered a lean-to shed next to your exterior wall, with a firewall between ?

icarus

Re: battery box venting

Zepher makes a battery box vent fan with integral damper, just perfect. You can run if off the controller so it only runs while charging, or make a voltage activated switch so that it only comes on when the battery can produce gas. I have mine set at 13vdc for my 12vdc bank. 12 and 24vdc models vent through a 2" pvc or abs vent. 48 through a 3" i believe.

I concur with Mike. I wouldn't run in either in the plumbing vent stack, or the bath "fart fan" vent. The problem with the plumbing stack is that you would need a trap to keep the sewer gas from passing into the battery box, or a mechanical damper. If you had a trap, even if a fan could evacuate the trap so that it vented, it couldn't reintroduce the water again. (You don't want to go to a trap primer)! I suspect that our inspection authority would frown on such a thing. I don't know of any exception in the UPC to allow such a thing.

As for venting into the "fart fan" you would need a damper to keep the hydrogen from getting A:into the bath fan where it could ignite since it is not an explosion proof fan and B: to keep the hydrogen from entering the bathroom.

Also, I suspect that you have the batteries in the attic area to shorten the run from the panels. You might consider the attic temp effect on battery life. I'm sure you know that while battery capacity is greater with warm batteries, battery life goes down dramatically with temp. I try to keep my batteries a cool as possible for the longest life.

Good luck,

Icarus

crewzer

Re: battery box venting

Zephyr fan info: http://www.solarseller.com/battery_box_power_vent_by_zephyr_industries.htm

HTH,
Jim / crewzer