My multiplus 24/5000/120/240 shuts down briefly when under load. I would guess maybe up to 4000w, so not close to its limit. However, I've never heard a fan come on. Does it have one? How do I check it's connections? Can it be disabled in ve config? I'm looking at increasing ventilation and external cooling, but my old phoenix 24/3000 didn't have this problem in the same location, and I could hear its fan kick in... Any thoughts?