<!DOCTYPE html>
<html>
  <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
  </head>
  <body>
    <p>Hi William;</p>
    <p>Poor ventilation could be part of it, but I've also seen
      corrosion problems from:<br>
      clients over filling the cells, <br>
      EQing to often, <br>
      absorption voltage set too high and for too long, <br>
      too high a charge rate, (too large an array)<br>
      too high a temperature, due to floor heating and/or insulated
      battery box. <br>
    </p>
    <p>my best systems seem to be on the lower side of array size
      relative to battery size, with batteries in a basement or garage
      that stays above freezing, but below 60F most of the year. <br>
    </p>
    <p>Sorry I don't have a line on explosion proof fans, but I have a
      client with a 120 vac radon blower for the battery exhaust that
      seems to do much better than the traditional DC battery fans. 
      (Not my install.)</p>
    <p> I've only seen batteries blow twice:<br>
      1) Idiot was arc welding next to a HUP battery and multiple large
      sparks went right on to a cap; result: blew the top off the cell.
      He had been told to construct a battery enclosure around the
      batteries, but never did. <br>
      2) a loose connection at a battery terminal arced, melted the lead
      until the molten lead melted through the top of the case and
      ignited the hydrogen, result: burned a clear flame for a few
      seconds and went out without any major damage. <br>
    </p>
    <p>So my take away is that unless the ignition source is in the cell
      or within an inch of the cap, the hydrogen is too low a
      concentration to ignite.  Actually, are lead acid battery internal
      plates and their external connections considered "explosion
      proof"?  <br>
    </p>
    <p>Ray Walters<br>
      Remote Solar<br>
    </p>
    <p><br>
    </p>
    <div class="moz-cite-prefix">On 5/6/2025 12:20 PM, William Miller
      via RE-wrenches wrote:<br>
    </div>
    <blockquote type="cite"
      cite="mid:77835f3af9807be52f0c3b6d81ca8891@mail.gmail.com">
      <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
      <meta name="Generator"
        content="Microsoft Word 14 (filtered medium)">
      <style>@font-face
        {font-family:Calibri;
        panose-1:2 15 5 2 2 2 4 3 2 4;}@font-face
        {font-family:Verdana;
        panose-1:2 11 6 4 3 5 4 4 2 4;}p.MsoNormal, li.MsoNormal, div.MsoNormal
        {margin:0in;
        margin-bottom:.0001pt;
        font-size:11.0pt;
        font-family:"Calibri","sans-serif";}a:link, span.MsoHyperlink
        {mso-style-priority:99;
        color:blue;
        text-decoration:underline;}a:visited, span.MsoHyperlinkFollowed
        {mso-style-priority:99;
        color:purple;
        text-decoration:underline;}span.EmailStyle17
        {mso-style-type:personal-compose;
        font-family:"Verdana","sans-serif";
        color:windowtext;}.MsoChpDefault
        {mso-style-type:export-only;
        font-family:"Calibri","sans-serif";}div.WordSection1
        {page:WordSection1;}</style>
      <div class="WordSection1">
        <p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Verdana","sans-serif"">Friends:</span></p>
        <p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Verdana","sans-serif""> </span></p>
        <p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Verdana","sans-serif"">I
            have two flooded battery arrays that have steel cases that
            are corroding.  I am sure poor ventilation is the issue even
            though we have passive vents high and low.  I think I need
            active ventilation.  </span></p>
        <p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Verdana","sans-serif""> </span></p>
        <p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Verdana","sans-serif"">Does
            anyone have knowledge of a 120VAC explosion proof ceiling
            mounted exhaust fan?</span></p>
        <p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Verdana","sans-serif""> </span></p>
        <p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Verdana","sans-serif"">Thanks
            in advance.</span></p>
        <p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Verdana","sans-serif""> </span></p>
        <p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Verdana","sans-serif"">William</span></p>
        <p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Verdana","sans-serif""> </span></p>
        <p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Arial","sans-serif"">Miller
            Solar</span></p>
        <p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Arial","sans-serif"">17395
            Oak Road, Atascadero, CA 93422</span></p>
        <p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Arial","sans-serif"">805-438-5600</span></p>
        <p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Arial","sans-serif""><a
              href="http://www.millersolar.com/" moz-do-not-send="true">www.millersolar.com</a></span></p>
        <p class="MsoNormal"><span
style="font-size:12.0pt;font-family:"Arial","sans-serif"">CA
            Lic. 773985</span></p>
        <p class="MsoNormal"> </p>
        <p class="MsoNormal"> </p>
      </div>
      <br>
      <fieldset class="moz-mime-attachment-header"></fieldset>
      <pre wrap="" class="moz-quote-pre">_______________________________________________
List sponsored by Redwood Alliance

Pay optional member dues here: <a class="moz-txt-link-freetext" href="http://re-wrenches.org">http://re-wrenches.org</a>

List Address: <a class="moz-txt-link-abbreviated" href="mailto:RE-wrenches@lists.re-wrenches.org">RE-wrenches@lists.re-wrenches.org</a>

Change listserver email address & settings:
<a class="moz-txt-link-freetext" href="http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org">http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org</a>

There are two list archives for searching. When one doesn't work, try the other:
<a class="moz-txt-link-freetext" href="https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/">https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/</a>
<a class="moz-txt-link-freetext" href="http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org">http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org</a>

List rules & etiquette:
<a class="moz-txt-link-freetext" href="http://www.re-wrenches.org/etiquette.htm">http://www.re-wrenches.org/etiquette.htm</a>

Check out or update participant bios:
<a class="moz-txt-link-freetext" href="http://www.members.re-wrenches.org">http://www.members.re-wrenches.org</a>

</pre>
    </blockquote>
  </body>
</html>