Say Dynon..

[pierre smith]

Last Sunday afternoon was very, very, hot and for the second time in July, my D-100 had a yellow warning on the screen while we were flying.."Temperature out of spec!" that I couldn't turn off or make go away.

Does this mean that the unit is undependable?...as in an IFR approach? Or is it just letting me know that it's hot?

Thanks,

[snowbird]

The same thing happened to me landing in Kansas City heat last month. The message is generated when the internal temp of the Dynon unit exceeds 150 degrees F.
The solutions available for me are more cooling air to the unit or stay in Canada in the summer.

[cfiidon]

I have a three port avionics cooling fan. As I only had two avionics ports to cool (GNS430 and GTX327) I asked Dynon where was the best place to supply cooling air to the D180. The reply was that localized cooling was not a good idea.

So... my third port hose goes up between the D180 and the radio stack and will blow air up to the top of everything to keep it all moving. I may put a vent or two up top to have someplace for it to go. Might also keep the ice off the windscreen :-)

Don

[Geico266]

It seems avionics cooling in the -10 is left up to chance. My Cheltons were getting pretty hot to the touch until I routed cooling air off of the fresh air vents. I visit to Home Depo into their airplane parts department will give you some ideas.

[Vern]

I've had the Dynon D100 in my 6A refuse to boot on engine startup due to being parked in the south Ga sun. After takeoff, it woke up while climbing out.

Right now, our RV-10 is having issues on with both the 696 and Garmin 530. Several times the Garmin has needed to be off until enroute. The SL-30 has no problems.

I'm about to replace the under-dash computer fan with an avionics multi-port fan.

Of course, in this heat, the pilot has been slow to get started also!

[CosmicHerb]

I had the same problem with my D-100, but living in Texas the heat just comes with the territory. We decided to go to lunch and I didn't bring my canopy cover with me and by the time we got back the interior was roasting. The Dynon D-100 was giving me an out of temperature warning. I have other back up instruments so I took off and got up to 6000 feet where it was much cooler and the D-100 came back to normal. I did notice that even when the out of temperature warning was on the screen the unit was still functioning like normal but it was all in black and white. Now I don't go anywhere with out my canopy cover and i put it on if I am going to close the canopy for any length of time at all. It is amazing how quickly they heat up.

[DFlyer]

The over temperature spec warning is just that; the sensors are outside of spec and therefore outside designed performance. We have never heard of a unit not giving reasonable output in that condition since we design in engineering tolerances, but you shouldn't rely on performance if outside of spec if you don't have to, just like any other aircraft spec.

In older versions of D10/D100 firmware, the attitude would change colors to black/white to draw attention to the warning. But in more recent versions, we've changed that to only paint the advisory message, as it does not constitute a critical or even expected loss of functionality. Rather, it's possible that performance could be degraded. In reality, we have not received reports that that hot units behave worse than when they are in-spec. Basically, the unit warns you that unit is being over heated, and you should know that that this means your radios and other electronics gear are probably beyond or near their temperature limitations as well. Just because your other equipment doesn't warn you, don't assume nothing bad is happening. The Dynon equipment is generally rated to similar temperature specs as most certified equipment. It is interesting to note that in many/most parameters we have to design our equipment to better than certified requirements, because it goes in so many different designs. We don't have the luxury of working with a type-certified aircraft manufacturer and making sure that an installation is adequate and repeatable, so we design for a much greater set of conditions.

On SkyView we designed the temperature to stay within specs in all reasonable installations even without the fans, and then added the fans to provide adequate cooling in extreme installations and situations.

-Robert
Dynon Marketing

[pierre smith]

I have an installed avionics cooling fan but I don't believe that any air is directed at the D-100 or the D-120. The OAT gauge showed 85 F but the sun was occasionally shining on the unit when the warning appeared. Will a small fan blowing at the rear help some?

Thanks,

[DFlyer]

Pierre, yes, any air movement helps and is the best solution to keeping avionics cool.

-Robert