Diagnosis
The MVH has a relatively high center of gravity and small, hard plastic feet. On thick carpet, these feet can sink in or tilt, making the unit unstable.
How to Fix It
You need to create a stable, flat platform. 1) Use a solid, level piece of wood, a small ceramic tile, or a firm plastic cutting board. 2) Place this platform on your carpet first. 3) Set the heater firmly on top of it. This distributes the weight and prevents the feet from digging in. Ensure the platform is wider than the heater's base for safety.
If That Didn't Work
Check that all four feet are present and intact. They can sometimes crack or break off. If one is missing, the heater will rock.
Heads Up
This is critical: The tip-over safety switch is in the base. If the heater is permanently wobbly or on an uneven surface, it might not tip far enough to trigger the shutoff in a real accident. Your fix with a platform must result in a rock-solid, level setup.