You could try washing before priming to remove any contaminates. Use a strong cleanser like trisodium phosphate (TSP). Something else to try is another type of primer. Oil based primers, like Kilz, do a good job and can stick to questionable surfaces.

Fixing the Bubbles

To better prep walls for painting in the entire home and address the bubbling spots caused by burnt candles, a thorough approach is necessary. Here are the steps you can take:

1. **Identify and Address the Root Cause**: Determine the extent of the damage caused by the burnt candles. If the bubbles are localized, lightly sand those areas to smooth them out. If the damage is widespread, consider stripping the affected areas down to the drywall and then patching them up before priming.

2. **Cleaning and Degreasing**: Before priming, ensure all walls are clean and free from dust, dirt, and any contaminants. Use a mild detergent solution to wash the walls, especially in areas where candles were burned, as soot and residue might be present.

3. **Repair Damaged Areas**: For any cracks, holes, or imperfections in the walls, fill them with a high-quality spackling compound and sand them smooth once dry. This will ensure a smooth surface for painting and prevent future issues.

4. **Priming**: Use a high-quality primer specifically designed for smoke and soot damage. Apply the primer evenly on the walls to seal in any stains and create a uniform surface for the paint to adhere to. This will also help prevent any further bubbling or discoloration.

5. **Choosing the Right Paint**: Opt for a paint with stain-blocking properties to further prevent any residue from seeping through and causing issues. Look for paints labeled as “stain-resistant” or “washable” for added durability and ease of maintenance.

6. **Proper Ventilation**: Ensure proper ventilation in the room while painting and priming to encourage faster drying and minimize the lingering smell of smoke or paint fumes.