Insulated Windows

[flyu2there]

I just picked this up from another source, pretty much says it all, I hope

"There are four ways to repair an insulated glass coach window.
1. Remove the insulated (IG) glass panel. Separate the two panes. Remove and clean off the sealant/adhesive/spacer (a tedious,time consuming job). Wash the glass panes with R/O water rinse. Re-apply the appropriate seal. Re-assemble the glass panes to form the IG unit. Press the new IG panel through rollers to ensure a good seal and uniform thickness. Re assemble IG panel to metal frame with glazing seal.
2. Remove the IG panel. Use it as a template to have new tempered glass panes made. Re-assemble as above.
3. Remove the IG panel. Send it out to a specialized IG unit source to use as a template to mfr. a whole new IG panel. Re-assemble as above.
4. Build a new window.
IMHO, the best way is #4. That way you get a complete new for which the manufacturer will generally provide a limited warranty. There are many pitfalls that can be encountered by a small glass shop trying to repair an IG panel as in #1. Most will not attempt it. Most would order a new IG panel the, install it to your frame (#2).
BTW, the IG panel is assembled with regular atmospheric pressure inside; not a vacuum. The heat transfer and sound insulation is provided as a result of the dead air space between the dual panes. If they used an internal vacuum atmosphere all of the panels would have concave surfaces due to atmospheric pressure outside (14-15psi). Very undesirable."

[BrianE]

Based on my experience with installing single pane windows in the Green Machine, I just changed out the windows on our Royale due to the same old bugaboo of internal fogging. Tom's windows are a complete window and frame replacement built by Peninsula Glass Co. http://www.peninsulaglass.com/. I took a little different approach to the Royale and replaced the glass with standard 1/4" tinted safety glass combined with a close cell seal to compensate for the difference in thickness of the dual pane windows. The tint is exactly the same as the windshield and is a big improvement in glare reduction.

I would be willing to take bets from anyone (John?) that a difference in sound level can't be detected. I guess it is possible that in extremely cold weather the dual pane setup might not fog as quickly, especially in a seated bus with 40 or so passengers.

[Jon Wehrenberg]

FWIW on my 87 coach the glass lens over the rear camera would fog up on cold nights. Taking a shower was a sure way to add enough moisture to the air on the coach side of the glass so I would not have any visibility for hours.

So I removed it, cut a matching piece of glass, and on one glass I drew a bead of silicone RTV sealer about 1/4" diameter around the perimeter. I then heated that glass up so it was too hot to touch, and placed the second piece of glass on top of the bead, wiggling it only enough to see that it was in perfect contact with the bead around its entire perimeter.

Then I just left it alone until the silicone cured.

RTV silcone has some characteristics that I tried to use to my advantage. First, by heating it up the air between the two pieces of glass was warm, and hoepfully had very little moisture in it. When I put the second glass on the bead, whatever air was trapped would cool, and pull a very small negative pressure. Since RTV absorbs moisture during its curing process (from the humidity in the air) I was hoping whatever small amount of moisture I had trapped would be absorbed by the RTV.

It apparently worked because after I installed that home made thermopane rear camera glass I never got fogging, and I never saw evidence of any dirt or foreign matter between the two pieces of glass.

The only downside, and the reason I probably will not try the same on the front side glass is that I didn't draw a perfect silicone bead, and it looked uneven. Since the rear camera fiberglass housing obscured the sloppy bead it did not matter, but on the front glass I'll wager it would be visible and look lousy. When I get around to changing my front glass I will likely use a single thick pane of safety glass.

[0533]

I had Prevost car replace (brand New) the front door movable window last June, it is now fogging again, the window is exactly one year old, definitely a flawed design, can't withstand the constant opening and closing of the door or was simply made poorly by the supplier.

PS> Thanks for reminding me, as all Prevost Car installs come with a One year warrantee. I just checked and it was installed at Prevost car Quebec last July 7, 2008. I am about to email Prevost to put them on notice.

[Jon Wehrenberg]

I have two foggy windows. I dealt with this issue on the first bus and I keep putting it off on this one because unless I take the single thickness glass approach this problem never goes away. Prevost has never sold side window glass that did not fog almost immediately and dealing with Sikaflex is very low on my list of things to do. I would rather change airbags.

I am likely to fix them before OKC, but I think I will do the repair myself by disassembling them and resealing them. I just have not decided how I want to do that. I am likely to follow John's recipe. I will not get replacements from Prevost.

[Gary & Peggy Stevens]

In this months FMCA magazine ( June 2009 ) in the Readers Forum on page # 20, there is an article from a member about his great experience with window replacement @

Suncoast Designers Inc.
15050 Labor Place
Hudson, Fl 34667
727-868-2773
http://suncoastdesigners.ccwindow.com/rvservices.html


No personal experience, just passing on the information.

Gary S.