What causes yellow stain on ceiling?

Regarding this, how do I get rid of yellow stains on my ceiling?

Conceal an unsightly water stain on the ceiling—and put a stopper on the leak that caused it—with these stain-fighting tips.

1. STEP 1: Identify and repair the root cause.
2. STEP 2: Clean the stain with bleach.
3. STEP 3: Apply a base coat of stain-blocking primer.
4. STEP 4: Cover the primer with ceiling paint.

Subsequently, question is, why does drywall turn yellow? Left unprimed, drywall starts to yellow within a few weeks. The yellow will bleed right through most lightweight joint compounds and typical drywall primers, which is why it's important to prime right after drywall finishing is complete. When the primer is dry, you can paint with a regular latex paint.

Likewise, what causes discoloration on ceiling?

When you see brown spots, or patches, on your ceiling and interior walls, they are water stains caused from a leak above. This leak could be a malfunction in your commercial roof systems or a leak with another part of your facility, such as HVAC units or leaking pipes.

What does a water leak look like on a ceiling?

If there is active water dripping, it will often be brown or dirty if it comes from the roof. Because ice dams occur along the edges of the roof, the ceiling damage or leaking is often near the edge of the room, or may even appear on an exterior wall, since the water may be dripping directly down into the walls.