Recommendations for a 12 volt windscreen heater/demister

Jurgen

Jurgen

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Hi all, motored back from OV on Monday morning in the rain, decided that the flybridge was no place to be so bugged out to the lower helm.
Within 5 minutes the windscreen had completely fogged up as we do not have blowers on our 2006 F43.
To that end can anyone recommend a good quality but more importantly efficient 12 volt heater/demister that can be dash mounted.
Many thanks
Andy
 
Andy,

We have demister vents from the Eberspacher. I assume you have a similar diesel heater, so could you trunk some hose up to your screen? Much better solution than 12v fan.
 
I fitted three 12V heater/demisters. A waste of space and money plus they make a lot of noise. You need something more powerful, like a diesel heater output, or a crew member with a cloth.
 
RAI said:
I fitted three 12V heater/demisters. A waste of space and money plus they make a lot of noise. You need something more powerful, like a diesel heater output, or a crew member with a cloth.
Click to expand...

I disagree.

I bought a couple of 12v fan heaters from Maplins, as the design of the boat interior prevents the fitting of ducted engine or diesel heated demisters.
The 12v fan heaters are almost silent in operation, (yes I was surprised too) and use around 15A each so you need to use suitably thick wire for their supply.
They keep a visible area of the windscreen clear quite effectively. Admittedly not as big a clear area as in a car, but effective enough for me to be happy with them.

Forget coating stuff on the screen, that just makes things smeary and messy.

Example demister similar to the ones I bought from Maplins: http://www.maplin.co.uk/p/in-car-ceramic-heatercooler-a75fl
 
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Was quite surprised to find that there were no outlets in front of the windscreen when we first looked at the F43.
Might see if I can get behind the dash to see if there's enough room for vents and ducting
 
There will be, as many 410/F43's have ducted warm air demisters. I've not seen the install myself, and getting behind the dash on these can be tricky, but it must be doable.
 
Trundlebug said:
I disagree.

I bought a couple of 12v fan heaters from Maplins, as the design of the boat interior prevents the fitting of ducted engine or diesel heated demisters.
The 12v fan heaters are almost silent in operation, (yes I was surprised too) and use around 15A each so you need to use suitably thick wire for their supply.
They keep a visible area of the windscreen clear quite effectively. Admittedly not as big a clear area as in a car, but effective enough for me to be happy with them.

Forget coating stuff on the screen, that just makes things smeary and messy.

Example demister similar to the ones I bought from Maplins: http://www.maplin.co.uk/p/in-car-ceramic-heatercooler-a75fl
Click to expand...

Thanks. Interesting solution. What size screen area does one of there clear?

Colin. Www.solocoastalsailing.co.uk
 
It clears an area of about 18 inches in diameter, which is enough to see out effectively if correctly positioned.

That is very approximate though and varies with conditions.
The same items are available from other sources and usually around Christmas time Maplins have a bit of a promotion on selling them at around a tenner.

I have seen similar 12v boat / windscreen demisters for sale in chandleries but don't have any direct experience with them so I can't compare their performance with the ones I have. I was genuinely amazed at how quiet they are - to the extent that I've had to fit illuminated switches to operate them, so I don't forget they are on. Even with quite thick wiring (about 8mm2) it does get warm after 10 mins or so.
 
Trundlebug said:
It clears an area of about 18 inches in diameter, which is enough to see out effectively if correctly positioned.

That is very approximate though and varies with conditions.
The same items are available from other sources and usually around Christmas time Maplins have a bit of a promotion on selling them at around a tenner.

I have seen similar 12v boat / windscreen demisters for sale in chandleries but don't have any direct experience with them so I can't compare their performance with the ones I have. I was genuinely amazed at how quiet they are - to the extent that I've had to fit illuminated switches to operate them, so I don't forget they are on. Even with quite thick wiring (about 8mm2) it does get warm after 10 mins or so.
Click to expand...

Thanks for helpful info.

Colin. Www.solocoastalsailing.co.uk
 
Trundlebug said:
It clears an area of about 18 inches in diameter, which is enough to see out effectively if correctly positioned.

That is very approximate though and varies with conditions.
The same items are available from other sources and usually around Christmas time Maplins have a bit of a promotion on selling them at around a tenner.

I have seen similar 12v boat / windscreen demisters for sale in chandleries but don't have any direct experience with them so I can't compare their performance with the ones I have. I was genuinely amazed at how quiet they are - to the extent that I've had to fit illuminated switches to operate them, so I don't forget they are on. Even with quite thick wiring (about 8mm2) it does get warm after 10 mins or so.
Click to expand...

Thanks for the recommendation.

I have now fitted one of the recommended 12v demisters sold by Maplin (currently priced at £7.50) and although I was not expecting much for the money it does work. After 4 minutes it had cleared a 250mm diameter area, which is better than nothing, and am hoping the area will increase in size over a longer period. This picture was taken after 4minutesdemister.jpg. You can see the Maplin demister to the left. Surprisingly, it does not affect the compass. You do need good wiring as this little device is rated at 150watts.

Colin. Www.solocoastalsailing.co.uk
 
Great stuff, I'm glad it's worked for you too.
I mounted mine so they point along and at a glancing angle to the windscreen, rather than at 90 degrees to it, so they clear a bigger area (rather like the vent from your car demisters). You may find that helps performance.

Yes I checked whether they affected my compass too, but they don't. I was surprised given the current they draw.
 
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