Rosacea can cause this, at least on the face.

It will cause a reddened appearance to the face and upper chest on me; I'd imagine that could reach to the top shoulders and across the top of my back too - never thought about it.

It feels like a light sunburn sometimes on my face.

Rosacea is an infection UNDER the upper layers of skin which causes inflammation. A person can use topical antimicrobials and oral antibiotics to control it, make it appear to be gone. But a few months after you stop taking the orals, it comes back. No worse than before really, just back.

Good luck!

YCM