Black soot marks or stains on the wall around a gas boiler, indicator of a combustion problem or possible carbon monoxide gas leak

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Size: 5568px × 3712px
Location: UK
Photo credit: © Sam Oaksey / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: appliance, black, blockage, boiler, carbon, combustion, danger, dangerous, gas, heating, home, indicator, leak, leakage, leaking, mark, marks, monoxide, problem, sign, signs, soot, stain, staining, stains