New idea: Okay I was thinking about why we call the diffuser, "diffuser," or "deflector". Well it does both, but we use it mostly as a diffuser--as it diffuses the fire and heat equally in all directions. I think of a deflector as shifting the heat in a specific direction. In order to do deflecting I would think you would have to tilt the deflector to increase flow in the direction desired. I have never seen any description of doing so.
Problem: MY 590 (and others I have read about) is cooler on the left side than either the center or right side:
With Mod and set at 225*, I get the following temps, Left Center 205* Center 227* Right Center 241-246*
So I lowered the right side of the Mod Plate by 1/4" by placing a nut between the plate and the deflector/diffuser at both right bolts. (no pics, sorry) which gives me a tilt that deflects more to the left side.
Result with deflection: Left Center 224-225*; Center 225*; Right Center 247. It took an some extra time to settle but was very stable at the endpoint. Almost unbelievable result, but it happens.
Impression: Makes sense and it worked, BUT had no apparent effect on the high right side. My diffuser/deflector was centered.
Question: What could make the right side significantly hotter than the left or center?
Answe?r:Drip pan is tilted downward to drain, and is significantly closer to the deflector on the right as it goes by, thus R drip pan is exposed to more direct heat and flame as it exits the d/d. Obviously the SS Mod plate lowered on that right side by 1/4" made little difference since the whole d/d is not lowered there.?? My assumption is that the drip pan is hotter in that spot and radiates that heat upward. Will look at the bottom of drip pan for any evidence.
What else could be done to lower temp on the right? Not sure anything is needed but to just know that and work around it or use it as needed.
Comment: I know that if I never knew there was a difference in grill temps from side to side, I would probably continue cooking great meals on this fine grill. I also know that this is not uncommon in most pellet grills on the market although the hot side is not always on the right.
Plan: Since I am old and unemployed, I will do a little more sleuthing before giving up on the right, but am very happy with the results to date and feel I have discovered new territory that might be worth a little research by the manufacturers to alter their rather rigid design concepts for diffuser/defectors (like adding little "tilt" where needed). Or maybe conclusions might include "Live with it! Its no big deal"