Veronica,
I have the older smaller 1/2-cousin to your stove
I pull my blowers off and clean them after every ton of pellets.
Have some mineral wool handy for gasketing material for the combustion blower.
If you have not cleaned your blowers in 3 years you probably have not pulled your stove apart to clean out behind the firebox. I also do this every ton.
I find the easiest way to deep clean the stove is to remove it from the house and used compressed air and a vacuum on the back porch or in the yard. I really open up all the areas of the stove and clean all the ash/crap out.
For the blowers I hit them with compressed air then soak the blades in mineral spirits. Then using and old toothbrush I clean the blades carefully (without bending them). Then I blow them dry with the air again. The combustion blower does not need oil as the bearings are sealed. The convection blower has 2 oil ports for 3 drops of light machinery oil (3 in 1 oil is what is commonly used) each.
Your stove will love you for it. And you should see a big improvement in your stoves performance.
Any questions....just ask.
Good Luck,
---Nailer---