REFLECTOR: GRT Displays overheating - Anyone else see this?

[Brett Ferrell]

We've had quite a string of hot weather here in SW Ohio as of late, and on
the last couple of flights we've had issues with our GRT HX screens
overheating and shutting down in flight.  We've got backup dial gauges, but
needless to say, it's disappointing when you lose the fancy readouts, and
though we've been planning to fly to Airventure we will likely won't if we
can't quickly find a solution to the issue.  Has anyone else seen this
behavior?  If so, how did you resolve it?

GRT tell me that the screens should run 'about 30 degrees' above ambient.
They will shut down at 160 F, and you can see the internal temperature by
going to setup menu (Display Maint, Analog Input page).  It's been right at
100 F here for the last few days, and I can confirm that on the ground they
warm right up to 130.  We went around the pattern and in less than two
passes they were shutting down!  I went to the setup page, and sure enough,
they were reporting in the mid 150s.

GRT believes that if I add vents to my glaresheild the issue will resolve
itself, but I have already tried a large (68 cfm) computer fan aimed at the
back of the displays, which only relieved about 1 degree F of temperature,
and tried routing cooling air from the nose fresh air vent to the back of
the displays to no effect (the screens still shutdown in flight).  I
believe my situation is unique because I mounted a second oil cooler in the
nose for winter recirculating air usage (rather than cold outside air), and
have checked this cooler is, in fact, getting quite hot.  On my last flight
it was over 200 F even though the one on the nose NACA was below 180, so I
think this cooler is just filling the nose area with hot air.  Net, I'm
going to pull that cooler, and at some point put vents in the glaresheild,
but that's a fair amount of effort the way I have it mounted.
Brett
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