It is important to report material changes to your insurer. This is true for all of your insurers, residential and commercial, not just the insurer protecting your home.  

Whether a change is material enough to require reporting is tough to comment upon in general terms.  That being said, I would say that installing a new wood burning stove in a home that did not have a wood burning stove before is a material change in risk.  Replacing an old electric cooking stove with a new electric stove is probably not a material change in risk, in most cases.

Underwriters provide insurance on the basis of the risk presented to them at the time.  If something changes the nature of the risk, it is better to over-report than not tell them at all.

This is a good reminder - keep your insurer in the loop.