I don't have an Everest, but faced the same issue with my convection dying after 9 years. I added 4 x 12 vents to the side compartments when I installed the new one in both the closet and in the adjoining cabinet. I'm not sure if it is necessary, but it seemed to be worth doing while I was in there. I put the metal grill in the closet and the kitchen cabinet. The walls are foam.
It seems common by looking at other RVs to not have enough clearance for convection ovens. I used my previous one for a long time before when it was cold. Other than that, I mostly did 15-20 minute stretches. Mine died when I was also running the furnace and ran for 1 1/2 hours.
'10 Ford F-450, 6.4, 4.30, 4x4, 14,500 GVWR, '06 Host Rainer 950 DS, Torklift Talon tiedowns, Glow Steps, and Fastguns. Bilstein 4600s, Firestone Bags, Toyo M655 Gs, Curt front hitch, Energy Suspension bump stops.
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