i just use an old processor heatsink and a pc fan on low (run on an old phone charger and so underpowered.)
to cool my magnetic ballast, it barely gets warm.
This is what I do also,but i use a transformer on a pc fan.
My problem with mag ballasts wouldn't be so much that there was a hot component in my growroom, but more than an excessive amount of waste heat was being generated in my growroom; a problem that cooling the ballast doesn't really solve. It just transfers the heat to the growroom quicker.
I would try that if I were running magnetic ballasts still. Back when I ran one I kept it outside of my grow tent, but it was still heating the room.
Right now I'm only running digital ballasts on 240v so it's a non-issue.
I'm still pretty surprised that a magnetic ballast will run hotter on 240v.
no they run maybe a little hotter on 240v
That makes sense to me because of the reduced amperage necessary, and I know that's how my digital ballasts work. This dude indicated the opposite was true:
digital all the way.
my main reason is they are safer and cooler
many brands have a feature thats called Cut-off circuitry
Lumatek E-Ballasts cuts off when a short is detected; for ultimate safety. Also has a built in feature that when i short occurs it will wait 30 minutes before re-igniting, cause everyone knows the bulb can't be powered up more than once in 30 minutes without damage...
they have OPEN circuit protection but believe me if they go short they go up in smoke
i've seen them handle a power outrage just like they say it should. I didn't ignite the bulb when power came back on in 6 minutes. It safely waited half an hour before re-striking the bulb.