condensation on instruments

[dubrus]

eveing folks,

looking for some advice on a this one.

my hummingbird 757c, quicksilver fuel, trim tab, speedo gauges all develop a little misting when turned on for a little while. seems intermittent if they will clear up or not.

since all the stuff is new to me is there anything i can do to fix this problem?

FYI the boat is always stored outside with a full cover over it.

nothing major but an annoyance an a quick search shows others have had problems but no real info as to a diy fix?

cheers

[BogMonster]

I think "it just happens" - not really sure why on supposedly IPX7 sealed instruments but all the gauges on my Humber and the fishfinder display used to mist up regularly. The only thing that didn't was the Icom VHF. Never seemed to bother anything though, which is odd.

[willk]

OK. In my right hand I have a Can of Worms, in my left, an Can-opener....

I had this problem with my older plotter. It had become almost useless in certain conditions. Anyway, I decided that I had nothing to loose.

I found a very small silica gel sachet (as packed in electronics boxes), dried it in the oven and placed it inside the back of the plotter housing. It worked VERY well for a few months but I now see a bit of mist reappearing. Have to go again with a drier and larger pack this time.

Plotters are not sealed, merely closed with a foam rubber O-ring (probably neoprene). As the unit warms and cools, damp air must be drawn in and when warm, the coolest, highest place for moisture to condense is the inside of the screen.

[biffer]

you can get silica in little round plastic tubes, i think mine came from a double glazing company, i think 3m sealer have something like it in the bottom of the tube, drill a hole in the back of the plotter and jam it in, when it's all used, take it out and jam in another one, jam is a technical term for push in tightly

[jambo]

Hi all the previous info taken can I also suggest that it is the cover that is generating the heat and cuasing the condensation as ther is no vbentilation,I have it. If it does not burn off and the sileca is taking to long, take out the bulb at the back and let it breath.I recently got a consol cover made with vents and it has stopped tyhe problem.
Hope it helps.

J

[dubrus]

i'll have a look this weekend at some options.

i'll try and find some of those silica sticks mean time.

cheers

[Cookee]

Originally Posted by dubrus

eveing folks,

looking for some advice on a this one.

FYI the boat is always stored outside with a full cover over it.

nothing major but an annoyance an a quick search shows others have had problems but no real info as to a diy fix?

cheers

Make sure the cover is ventilated, the humidity in a sealed cover combined with heat variations are going to make it difficult for anything to cope.

[dubrus]

vented in what way?

the cover is hardly a brilliant fit with air gaps here/there?? the cover is a full boat cover if i hadn't made that clear.

cheers

[willk]

Oh here, I misread your OP. I thought it was just the plotter. They're right about the cover ventilation - warm damp air rises under the cover. I have a couple of clamshell vents in my cover, up high near the console. I think a vent in the console is a plus too, that or leave the hatch open (under the cover)

[SeaSkills]

On (most of) my instruments I find that if I turn the backlight up to it's max, the warmth generated by the light clears the condensation