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Foretravel Motorhome Forums => Foretravel Tech Talk => Topic started by: Michelle on May 26, 2011, 02:00:28 pm

Title: Desiccant option for the HWH system
Post by: Michelle on May 26, 2011, 02:00:28 pm
After paying almost $50 for a 4 ounce bag of indicating desiccant, Steve did some research and came across

Bulk Sorbents - SorbentSystems.com (http://www.sorbentsystems.com/bulksorbents.html)

Mylar® and Foil Ziplock bags - SorbentSystems.com (http://sorbentsystems.com/stockziplock.html)

We bought the 5 pound can of blue indicating silica gel 2-4 mm for $25.75 and 100 of the open top mylar foil zip top 5.5" x 5.25" (055MFD0525OZE) bags for $50 (which unfortunately are not currently available on-line in quantities less than 1000.)

Weighed out portions of the desiccant, manually forced the air out of the mylar bags before zipping shut, and used our home Foodsaver to heat-seal the zip-tab end (sealing only, not vacuum-packing; it seemed to work OK).  Now we have 20 pre-packaged, moisture-sealed portions of desiccant and 80 bags leftover for future use.  Factoring in shipping, cost per portion was around $2.50 instead of near $50. 

The selected media item is not currently available.

Michelle
Title: Re: Desiccant option for the HWH system
Post by: wolfe10 on May 26, 2011, 02:35:54 pm
Michelle,

Sounds like the beginnings of a Cottage Industry!

Brett
Title: Re: Desiccant option for the HWH system
Post by: George Hatfield on May 26, 2011, 03:30:02 pm
I'd like to order 5 bags at your convenience!
Title: Re: Desiccant option for the HWH system
Post by: Kent Speers on May 26, 2011, 04:34:51 pm
After paying almost $50 for a 4 ounce bag of indicating desiccant, Steve did some research and came across

Bulk Sorbents - SorbentSystems.com (http://www.sorbentsystems.com/bulksorbents.html)

Mylar® and Foil Ziplock bags - SorbentSystems.com (http://sorbentsystems.com/stockziplock.html)

We bought the 5 pound can of blue indicating silica gel 2-4 mm for $25.75 and 100 of the open top mylar foil zip top "O" bags for $50 (which unfortunately are not currently available on-line in quantities less than 1000.)

Weighed out portions of the desiccant, manually forced the air out of the mylar bags before zipping shut, and used our home Foodsaver to heat-seal the zip-tab end (sealing only, not vacuum-packing; it seemed to work OK).  Now we have 20 pre-packaged, moisture-sealed portions of desiccant and 80 bags leftover for future use.  Factoring in shipping, cost per portion was around $2.50 instead of near $50. 

Michelle

Michelle, after seeing that the retail price desiccant is $50 and that there are others interested in purchasing some desiccant bags from you, I thought I should let you know you dropped a decimal when quoting the cost. You did mean $25.00 not $2.50. My customary commission rate is 20%.
Title: Re: Desiccant option for the HWH system
Post by: Michelle on May 26, 2011, 04:43:31 pm

Michelle, after seeing that the retail price desiccant is $50 and that there are others interested in purchasing some desiccant bags from you, I thought I should let you know you dropped a decimal when quoting the cost. You did mean $25.00 not $2.50. My customary commission rate is 20%.

Thanks, Kent.  Actually, we haven't decided if we're going into the "ForeForums-brand Aux Compressor Desiccant packet" business just yet  :))  There's a limited market now that the new Nimbus and Phenix coaches don't appear to use it for their systems.  I'd hate to ramp up production, hire all those employees, and then have demand crater.

We would, however, trade George Hatfield two bags for a couple of green chile cheeseburgers if we're ever in New Mexico at the same time  ;)

Michelle
Title: Re: Desiccant option for the HWH system
Post by: jeff on May 26, 2011, 07:40:13 pm
Michelle,

Those green chili cheeseburgers are worth WAY more than that. 
Title: Re: Desiccant option for the HWH system
Post by: Brad & Christine Slaughter on May 27, 2011, 09:36:12 pm
Try:  https://secure.drierite.com/catalog3/page4b.cfm
Not sure what the mesh size needed is, but there appears quite a range of indicating desiccant in the 1 pound size from $10.51 to $10.94.
Title: Re: Desiccant option for the HWH system
Post by: Brad & Christine Slaughter on May 27, 2011, 09:38:01 pm
Another useful page, instructions on how to regenerate your desiccant.
https://secure.drierite.com/catalog3/page19b.cfm
Title: Re: Desiccant option for the HWH system
Post by: George Hatfield on July 09, 2012, 03:21:09 pm
Concerning the above link, Drierite is not silcia gel, but is a desiccant made from anhydrous Calcium Sulfate.  The regeneration process is similar, but special care must be taken with silica gel so the internal structure of the crystals is not damaged.  That structure is what gives it such a large surface area to combine with water molecules.  Here are some good directions I found on the web.

"Regeneration of Silica Gel is done by heating the crystals in an oven at a temperature of not more than 300° F (149° C) for approximately three hours or until the crystals turn blue or transparent white. Dehydrating the desiccant may also be accomplished by heating in a microwave oven. Using a 900 watt oven heat the crystals for three minute intervals until the color change occurs. The exact amount of time necessary will depend upon the oven wattage. Spreading the desiccant in a broad pan in a shallow layer will speed the process. Heating to 325° F (149° C) or more, or using a microwave oven over 900 watts can damage the gel and render it unable to adsorb moisture."

I used the Sharp microwave in our coach (850 watts) and it started turning blue in about 1 minute and the drying was complete (at least as indicated by the blue color) in three minutes.  The blue color is from a small amount of cobalt chloride which is added to the silica gel as an indicator.  Anhydrous cobalt chloride is blue. When it bonds with two water molecules, (CoCl2•2H2O), it turns purple. Further hydration results in the pink hexaaquacobalt(II) chloride complex [Co(H2O)6]Cl2.

Here is a good link on all of this....  :: Abbas Products :: (http://silicagelpouch.com/about.html)
Title: Re: Desiccant option for the HWH system
Post by: Dean & Dee on July 09, 2012, 04:58:48 pm
                   I looked into going the same route as Steve and Michelle but when I placed the order with Sorbent they were out of the blue desiccant. They told me they could provide orange which turns to green.
    After some research I found out that the orange is much less toxic than the blue as it is not infused with Blue Colbolt Cloride. It appears to be a "greener" alternative.
          All the other properties are similer so I ordered it. I just have to make a new label for the desiccant canister so there is no future confusion on color changes.

                  Dean
Title: Re: Desiccant option for the HWH system
Post by: philtravel on July 09, 2012, 10:02:29 pm
Ok, I am feeling stupid I have no idea what you all are talking about! ????
Title: Re: Desiccant option for the HWH system
Post by: George Hatfield on July 09, 2012, 10:22:05 pm
On my coach the air pump for the slide has a bowl of silica gel desiccant that dries the air entering the pump.  If you don't have a slide, you probably don't have this setup.  It is my understanding that some of the older slide coaches (e.g., 1999 and 2000) don't have this either.  Below is a photo of a similar system.  Note the water in the 1st and 3rd traps?  Also, the desiccant needs to be replaced.
Title: Re: Desiccant option for the HWH system
Post by: Dean & Dee on July 10, 2012, 12:15:37 pm
                               Just for giggles I thought I would try regenterating the old desiccant while waiting for the new stuff to arrive. After killing the 12 vdc power I removed the canister and dumped the desiccant on a paper plate. Then put it in the coach micro for about 4-1/2 minutes total. Surprisingly about 75% of it turned blue.
                      D&D
Title: Re: Desiccant option for the HWH system
Post by: gam on July 10, 2012, 06:12:12 pm
Has anyone check the msds for this stuff? Gam
Title: Re: Desiccant option for the HWH system
Post by: George Hatfield on July 10, 2012, 06:17:38 pm
Can't speak to Cobalt Chloride (the blue/pink indicator), but silica gel is basically highly purified sand.  I would think it is very inert and presents little danger hot, cold or otherwise.

Update....  Lots of MSDS info on the web.  Here is one for the desicant with cobalt chloride

https://miltonindustries.com/uploads/MSDS_SHEET_FOR_DESSICANT_BEADS.pdf (https://miltonindustries.com/uploads/MSDS_SHEET_FOR_DESSICANT_BEADS.pdf)
Title: Re: Desiccant option for the HWH system
Post by: Dean & Dee on July 10, 2012, 06:19:18 pm
                 The MSDS is available at most websites that sell desiccant including Sorbent's.

            D&D
Title: Re: Desiccant option for the HWH system
Post by: Dean & Dee on July 17, 2012, 05:36:35 pm
                                 So I received my "Orange" desiccant from Sorbent yesterday and this afternoon we went into the packaging phase similer to Steve and Michelles original operation with one exception. After some Google search's I found that a $15.00 Wally World hair flat iron works very well to seal up Mylar bags.
              Pretty happy with the results. $11.48 for the Mylar bags shipped, $42.00 for the orange indicating desiccant, and $15.80 for the flat iron because Dee wouldn't let me use hers. ::)

              D&D
Title: Re: Desiccant option for the HWH system
Post by: Michelle on July 17, 2012, 05:44:22 pm
After some Google search's I found that a $15.00 Wally World hair flat iron works very well to seal up Mylar bags.

AB would be so proud - a multitasker!

Quote
Pretty happy with the results. $11.48 for the Mylar bags shipped, $42.00 for the orange indicating desiccant, and $15.80 for the flat iron because Dee wouldn't let me use hers. ::)

Hmmm... I wonder if you can use a flat iron to reseal white corn tortilla chip bags (like the one I see with a clothespin on it in one photo ;)  )?  We used to have a little bag resealer that worked off batteries.  It would help you ROI that flat iron even further (and be useful with all this humidity we're experiencing in Maine).

Michelle
Title: Re: Desiccant option for the HWH system
Post by: Dean & Dee on July 17, 2012, 06:06:15 pm

Hmmm... I wonder if you can use a flat iron to reseal white corn tortilla chip bags (like the one I see with a clothespin on it in one photo ;)  )?  We used to have a little bag resealer that worked off batteries.  It would help you ROI that flat iron even further (and be useful with all this humidity we're experiencing in Maine).

Michelle
                  Hmmm, you may be onto something. I may just try that and see what happens, but then what will we do with all these clothespins. I know of no other good use for them... :))

                D&D
Title: Re: Desiccant option for the HWH system
Post by: Dean & Dee on July 17, 2012, 06:11:42 pm
                         I took a photo of a few desiccant beads that attempted to escape the mylar bagging. Notice that a few have turned green from some humidity or moisture they came in contact with.

      Dean
Title: Re: Desiccant option for the HWH system
Post by: Michelle on July 17, 2012, 07:00:36 pm
                        I took a photo of a few desiccant beads that attempted to escape the mylar bagging. Notice that a few have turned green from some humidity or moisture they came in contact with.

Nice, distinct color and darkness change ^.^d  I like that better than the "orange to clear" some companies have for the non-cobalt-chloride option.  Good find!

Michelle
Title: Re: Desiccant option for the HWH system
Post by: Dean & Dee on July 17, 2012, 07:16:26 pm
Nice, distinct color and darkness change ^.^d  I like that better than the "orange to clear" some companies have for the non-cobalt-chloride option.  Good find!

Michelle
                                Thanks, and btw karma to you guys for pioneering the "bulk desiccant" frontier. Every $ saved on maintenance is a $ for the diesel tank!
 
                    D&D

                       
Title: Re: Desiccant option for the HWH system
Post by: Brad & Christine Slaughter on June 13, 2015, 01:11:18 am
So, Michelle:  Are you and Steve still in the desiccant business?  I think I need to replace mine....
Title: Re: Desiccant option for the HWH system
Post by: Brad & Christine Slaughter on June 13, 2015, 01:20:20 am
Is this a good choice if you aren't?  1 Quart Jar of Replacement Desiccant Blue Indicating Silica Gel 1 Qt Volume... (http://www.ebay.com/itm/1-Quart-Jar-of-Replacement-Desiccant-Blue-Indicating-Silica-Gel-1-Qt-Volume-/181124339162?)
Title: Re: Desiccant option for the HWH system
Post by: Jimmyjnr on June 13, 2015, 09:14:11 am
I need some too
Title: Re: Desiccant option for the HWH system
Post by: Michelle on June 13, 2015, 10:32:50 am
So, Michelle:  Are you and Steve still in the desiccant business?

We never were  :)

I don't recall the specifications when we researched alternatives, so I don't know if the eBay item is compatible or not.