Question on what vent is for

[JMGJR]

Anyone know what this vent is for (2021 3855BR with Legacy )? Been sitting here all day alone with nothing on except lights (no heat or AC or any fans) and I keep hearing it go on and off every once in awhile? Does it have anything to do with the built in surge protector on legacy package?

[Carl n Susan]

That is the vent for the 12V converter. There is a fan which cools the converter when it is running. But with just lights on, I wouldn't expect to hear it. You might want to check the water level in your batteries.

[lewy64]

i think this is what is going on, simple search of the forumns
https://www.montanaowners.com/forums...ad.php?t=75162

[JMGJR]

Thanks for responding. I love this user forum-so helpful! I should say that the residential fridge is also on but I will check the batteries. I've only had it about 4 weeks so I hope they are not low yet

[Daryles]

Inside the panel you will also see a green LED. This is the charge wizzard mode light. You can look up the mode blink codes on Progressive Dynamics webpage.

[DutchmenSport]

Yes, that is the vent for your power converter. The DC side kicks on and off when any item is running, like RV refrigerators on DC, propane detectors, led lights on your entertainment system, the controls in your water heater, any light switches or electronics running on DC power that has led lights, anything like that.

If you flip on one overhead light, you'll hear it run louder. Flip on two lights and it increases as the fan runs harder, flip on everything, and it's putting out power to all your DC electronics, even louder In addition, it's also keeping your house battery charged.

Contrary to thought here, your DC system electronics do not actually receive power from the battery. They receive power from the converter, and if more power is needed (say, a slide out), the converter alone will not have enough "umph" to move the slides. It takes the extra "umph" from the battery to actually move them.

What you are hearing is perfectly normal.