Garmin 430W Overheating - Suggestions

Situation: Radio stack is a PS Engineering PAR100EX with a Garmin 430W below with minimum clearance mounted in the center of my RV9A panel. I have added a small avionics blower, located on the right front side of the subpanel, to the Garmin to reduce the possibility of overheating and having the screen fade or go blank, which I have experienced on hot days in the past. I have a padded covered black glare shield with 3/8 inch foam backing.

Last weekend at the pancake breakfast at Twin Oaks, the plane was park in the sun for about one hour with outside air temperature about 70 degrees. When I opened the slider canopy, it was quite warm inside. Within 10 minutes after taking off and climbing to 3500 feet the 430W screen began to fade and became unreadable. During the course of the next 40 minutes or so, I shut the unit down to let it cool, restarted it with limited success. Eventually I shut it off for the duration of the flight relying on my second radio. During the flight the panel was quite warm and, reaching under the panel to feel the 430W case, the case was very hot to the touch. After I landed, I again reached under the panel and touched the case. It was very hot. I have since checked to confirm the avionics blower was working and the line to the 430W was unobstructed.

Diagnosis: My conclusion to this point is that the area under the glare shield had gotten too warm from sitting in the sun when the plane was parked and later from heat from the firewall to allow for cooling the 430W, though not noticeably warm to pilot and passenger. (Note, I ran the 430W on the ground for 45 minutes the next day. It did not heat up.)

Question: Has anyone had a similar experience and if so, what solutions have they tried and implemented. I will be using a canopy cover in the future and make sure that I keep the canopy open when sitting out in the sun. That said, I am not sure that will be sufficient given that I am having this problem on a 70 degree day.

John

Fail to boot

Ill be watching this thread with interest, I have had mine fail to boot once after sitting on the ramp at Mojave for the day. It locked up on the boot screen that shows software vs. IIRC, but the display was normal. It booted after 10 min or so of flight, and always since. I suspected it was either heat or an issue with not reading the data card.

Just a quick question, but did you put any sort of "vent holes" in the glareshield? If not, this is a must in these RV's, otherwise you're just making a fancy oven underneath the glareshield behind the panel....it's also what is Northern folks use for a defroster (with a small muffin fan in those said holes).

Cheers,
Stein

JVolkober said:

I have added a small avionics blower, located on the right front side of the subpanel, to the Garmin to reduce the possibility of overheating

Click to expand...

John,
Do you have it attached to the air hole on the connector backplate? I asked my avionics mentor (certified avionics shop GM) about that and he said he doesn't see them installed and doesn't see problems. I'm also watching this thread as I have the exact same setup although I haven't flown yet.

Another idea, the RV12 uses two fans on the floor behind the panel. One is blowing cool air into the area, and the other is pulling the heated air out. Seems like a neat idea that seems to work well.

larrynew said:

John,
Do you have it attached to the air hole on the connector backplate? I asked my avionics mentor (certified avionics shop GM) about that and he said he doesn't see them installed and doesn't see problems. I'm also watching this thread as I have the exact same setup although I haven't flown yet.

Click to expand...

I sort of depends on how/where it was installed. Many times we install cooling fans for the avionics, sometimes we don't. If it's in the middle of a big stack without much ventilation in the avionics bay, then yes a fan/hose would be a very good idea. Conversely, if it's installed nearly on it's own in a well ventilated area, then probably not too big of a deal. Either way you should have some sort of vent holes in the glareshield...if not you'll just end up recirculating lots of warm air.

Cheers,
Stein

Response to questions

The blower is attached to the port at the back of the chaise. Frankly, I do not detect much additional air flow through the bottom of the 430. Perhaps there are other places for the air to exit. And as Stein has suggested, its probably just warm air in any event until I can devise a method for getting cooler air up there.

The thought of putting in vent holes in my nice padded glare shield is unsettling but may be necessary. A lot of effort and dollars went into it looking for that finished look.

John

SteinAir said:

Either way you should have some sort of vent holes in the glareshield...if not you'll just end up recirculating lots of warm air.

Click to expand...

Any recommendations on how big these holes should be? And where to place them?

It is not important where the holes are, but that they are there. Also, I'm not an advocate of simply punching a bunch of ugly holes and leaving it be. We use some nice "grates / vents" that are usually painted to match the glareshield, that way they actually look good, not bad. I've seen people use bushings, grommets, automotive heater vents, computer case vent screens, etc...

This is one of those areas where you can't let vanity and form take over safety and function.

Cheers,
Stein

Like this


Then finish them like this....




Now you have a defroster!

John, have you verified that the 430's fan is working?

I forgot about that. I live in the southeast and it gets way hotter than Washington state and I have never had an issue.

Garmin 430W Overheating - Update

Following is an update based on a 1.5 hour flight today.

Before going out, I manually set the contrast on the 430W to 125, something I picked up while researching this issue in the past. This overcomes the tendency for the screen to fade out. I suspect if the unit gets hot enough even this will not work. Garmin recommends increasing the contrast as a solution to screen fade cause by high heat. Garmin also specifies that the maximum continuous operating temperature is 55 degrees centigrade (131 degrees Fahrenheit) , 70 (155 degrees Fahrenheit) for short periods of time. I am not able to measure how hot my unit gets, but to the touch it is very hot.

During this flight the unit again became very hot to the touch. The screen however remained very readable. I landed mid-way in the flight to check the temperature. I did the same at the end of the flight. My observation is that there is very little heating coming from the glare shield. Also, the air temperature between the panel and subpanel and in front of the subpanel was warm, but not excessively. What were very hot were the firewall and the subpanel and the Garmin case both of which face the firewall (the Garmin chase protrudes through the subpanel). It is clear to me that the heat radiating from the firewall is the main cause of the Garmin getting hot. While adding vents to the glare shield may allow the warm air to escape, I doubt that it will be sufficient to reduce the high temperatures cause heat radiating from the firewall. The solution, in my mind, is to cover the backside of the firewall with insulating material. During the build, I cut out sections of an insulating mat to fit between the various angle pieces on the firewall. However, I never installed them. Over the next couple of days, I will be installing the material to see if this will mitigate the heat issue.

So in short, my approach will be 1) when parking out in the sun, open the canopy and/or use a canopy cover to reduce the heating in the cabin 2) adjust the Garmin's contrast to improve the readability of the screen, and 3) install insulating material on the firewall to cut down the amount of radiant heating projected onto the subpanel and the Garmin case.

I will update this thread with the results.

John

AlexPeterson said:

John, have you verified that the 430's fan is working?

Click to expand...

Yes, the fan is working.

John

John,

I have a full Garmin stack that includes a GNS530W and I have not had any heating issues here in Washington or while traveling to AirVenture2012 where I landed and heat soaked my RV-9A in 100+ temps.

I contribute this to having a single 2.5" defrost vent on the glareshield on the pilot side. I believe is helps the trapped heated air to exit. I also have turned on the defrost fan while running on the ground to help circulate the air until I'm flying in cooler air. I'm considering adding a 2nd defrost grill on the co-pilot side to further help vent trapped air although it's probably not necessary.

For my glareshield, I have the padded edge from ClassicAero and simply painted my glareshield flat black. I do plan on adding some black velvet on top of the glareshield in the future to avoid scratching the paint.

Hope this helps.

I couldn't decide and finally started drilling holes to make a grill, computer fans mounted underneath.

While the radiant heat may be a part of the issue, I'd guess it to be very small amount, because the actual exposed backplate isn't part of the 430 itself. It's also covered in connectors and is only connected to the actual unit through part of the tray and friction connections from all the pins. Your solution certainly can't hurt (I'm a huge fan of firewall insulation for lots of reasons), but you'd be surprised how little air movement it takes around your avionics to cool them. Keep us posted as to your progress....I'd still urge some sort of at least basic ventilation!

Cheers,
Stein

SteinAir said:

While the radiant heat may be a part of the issue, I'd guess it to be very small amount, because the actual exposed backplate isn't part of the 430 itself. It's also covered in connectors and is only connected to the actual unit through part of the tray and friction connections from all the pins. Your solution certainly can't hurt (I'm a huge fan of firewall insulation for lots of reasons), but you'd be surprised how little air movement it takes around your avionics to cool them. Keep us posted as to your progress....I'd still urge some sort of at least basic ventilation!

Cheers,
Stein

Click to expand...

Given your experience and the previous note from Kevin, I can see the possibility of air vents in the future. Since I have to cut through and then tidy up the edges of the padded glare shield, I could use suggestions on how to finish the edges of the opening, some kind of lover or frame.

In the mean time, I will continue with my plan to insulate the firewall. Will be interesting to see if I get a noticeable reduction in heating.

John

Since you live in WA I'd suggest you just bite the bullet and put in the vent. (I used computer fans, always on unless the CB is pulled). Sooner or later you are going to want the defroster.

Another hole pattern

Cutting these fan holes was a slow and tedious process that I wouldn't want to attempt on a completed airplane but I'm happy with the results. I've never had a problem, even after sitting on the ground several times in 100+ degree heat.

Vent and fan size?

BobTurner said:

Since you live in WA I'd suggest you just bite the bullet and put in the vent. (I used computer fans, always on unless the CB is pulled). Sooner or later you are going to want the defroster.

Click to expand...

What size is your vent and fan? I am looking at some vent and fan alternatives. Looking are manufactured stuff, I located a 3" x 5 1/2" flush mounted louver or a 3 5/8 rectangular louver to put on top of a round hole for a 2.36 diameter (60 mm) fan. One on the pilot side and one on the passenger side.

John

I wrestled with ventilation issues during construction. I have my audio panel over a 430w over an ic210. All stacked close. I rejected cooling fan installations and installed a 'T' fitting on the passenger air vent instead. Some of the ram air from outside goes to the vent but the other half constantly blows over the avionics stack. Louisiana summers are freaking brutal but i have never had a 430 shutdown due to heat.

I have two computer fans, 3" or 90 mm, I forget which.

Years ago Cessna vented outside air to the avionics in 182s. They stopped doing it after they found rain water was getting in too.

Update

Well, I installed insulation material on the firewall with no appreciable effect on the heating issue. With the change in the contrast setting, the screen did not fade out. I discussed with Garmin and confirmed that the max contiguous temperature is 55 degrees centigrade and that I should get an on screen warning if the unit gets too hot. So at this point, I will be watching for the warning and screen fade. I plan on obtaining temperature strips to attach to the case to see what the actual temperature is. If it is 55 centigrade degrees or less, I'll leave it be. If not, then venting is in the future.

John

dahugo said:

I wrestled with ventilation issues during construction. I have my audio panel over a 430w over an ic210. All stacked close. I rejected cooling fan installations and installed a 'T' fitting on the passenger air vent instead. Some of the ram air from outside goes to the vent but the other half constantly blows over the avionics stack. Louisiana summers are freaking brutal but i have never had a 430 shutdown due to heat.

Click to expand...

In my -7, that vent fills with some water after a rain. Open the gaspers and I get a little spray. Can't say for sure, but I hope that water doesn't find its way right into your 430w.

John, you said you mounted a "small fan." Is this an overpriced avionics fan or a really small fan? Perhaps the volume of air you're moving through the tube to the cooling port is insufficient.

Also, you might think about where the fan is mounted. Is it pushing hot air (from near the firewall or up higher) to the 430, or cooler air from a lower location?

does the NAV work? (VOR/ILS)

Mine was overheating, the navboard was fried....everything but VOR and ILS worked (it would tune/ident one, but would never show on CDI)

I'll be trying two of these. Mounted close to the center radio stack in the forward outboard corners ahead of the panel and before the center subpanel. It was the most common size at the computer store (80mm) and the most quiet. I also got a grill to cover the exposed blades that exactly match the ones on the cooling fans for the Skyviews. Will double as defrosters.

Update to Update - Problem Solved - Insulation Worked

JVolkober said:

Well, I installed insulation material on the firewall with no appreciable effect on the heating issue. With the change in the contrast setting, the screen did not fade out. I discussed with Garmin and confirmed that the max contiguous temperature is 55 degrees centigrade and that I should get an on screen warning if the unit gets too hot. So at this point, I will be watching for the warning and screen fade. I plan on obtaining temperature strips to attach to the case to see what the actual temperature is. If it is 55 centigrade degrees or less, I'll leave it be. If not, then venting is in the future.

John

Click to expand...

For those of you reading this thread, I need to update my findings less you come to the wrong conclusion. When I return to 29JV after this flight I notice that the heater vent pull was out about 3/4", the heater vent was open during the previous flight. Since installing the insulation, and keeping the heater vent closed, I have had several flights taking off in very hot conditions - 98 degrees at Montague after sitting on the ground for an hour and today 98 degrees at Sunriver. There was no, the Garmin unit did not get hot. The panel was at most slightly warm. So, either the heater vent was open on all the previous flights where the Garmin 430 and panel were getting very hot, or the insulation really did cut out the radiant heat projecting from the firewall to the subpanel and panel. In any event, I no longer have a problem with the Garmin overheating. No vents required.

John