Odd fan in inverter compartment - what for?

[Steve P]

This fan is on the back wall of my right rear bay with a small fuse and relay block as well as the Magnum inverter.  The bottom of the cover was full of dirt from the bottom of the cover up to the bottom edge of the fan housing... I had never noticed it before, but I've recently begun looking "up" for things not in my initial sightlines.  I'm wondering what makes the fan run and whether it draws air into the compartment or pushes it out.  I didn't have time to mess with slides and jacks today, so I didn't even turn on the ignition key.  I'll poke around the back end with a good Streamlight tomorrow to see what the fan is connected to, if anything.  Does anyone else have one of these?  Maybe it just cools the inverter compartment? 

Thanks, 

Steve P

[MrAmbassador]

It is there to keep the compartment flowing with fresh air in an effort to keep the inverter from over heating. When you trace the wires it leads to a thermostat button switch that turns on the fan that draws sir in. The button typically has a number on it that you can google to find our at what temperature it closes and turns on the fan. Hope this helps! Safe travels!!!

[MyronTruex]

Magnum Inverter Compartment Cooling fan.pdf

 

[Steve P]

Thanks gents... I'm now looking for the snap disc and fuse.  Is that snap thingy responding to actual temp or "real feel"?  Just kidding!!

[Tom Cherry]

30 minutes ago, Steve P said:

Thanks gents... I'm now looking for the snap disc and fuse.  Is that snap thingy responding to actual temp or "real feel"?  Just kidding!!

Look at the print.  This isn’t a control device for a NASA space capsule surface cooing system.  The closer to the Magnum/Inverter, the better.  Use the temp range on the print.  Mount it where is will react or measure the encapsulated or dead air in the bay.  

[Steve P]

4 hours ago, Tom Cherry said:

Look at the print.  This isn’t a control device for a NASA space capsule surface cooing system.  The closer to the Magnum/Inverter, the better.  Use the temp range on the print.  Mount it where is will react or measure the encapsulated or dead air in the bay.  

Yup. The print is as basic as basic gets.  I'm just going to follow the wires.  If I need help, I do have friends at NASA.  Thanks! 

[Steve P]

I found the temperature snap disc and bypassed it with a nail and the fan worked fine.  Couldn't find the fuse, but  Obviously it's good. Then I got out the heat gun and gently warmed the snap disk until the fan came on to prove that it worked.  So all good!  On to the other projects...

[olywrestle]

I decided I would check to see if my fan was working, and it is, but while I had it off I grabbed the part numbers off the snap disk:

PN: 36T22 10847   
It is a Close on Rise with 120°F Cut-In and 90°F Cut-Out

I did find a alternative made NTE that would also work.

PN: NTE-DTC120
Close on Rise and Open at 95°F and Close at 122°F

 

Edit, looks like the one on the diagram is on at 110°F not 120°F like mine, but haven't found one with those specs yet.

Edited September 14, 2023 by olywrestle

[MrAmbassador]

Just an FYI, that fan runs off the Chassis batteries. So if it runs for a long time, it can run these batteries down and your Coach will not start, unless your inverter charges the Chassis batteries, mine does not. HVe a great day!!!