Clean up all the soot and rust that has vibrated loose and fallen below the burner with a wire brush.This could be causing a buildup.
Check the cooling unit if the refrigerator is not cooling at all. Check the temperature setting. This may need to be replaced.
Check to see if the unit is level. When a refrigerator is not leveled it often causes blockages in the cooling unit because the solution inside the coils crystallizes and drops to the bottom. This solution should be moving freely through the coils. If this is the problem, tip the unit over to break it loose.
Look for a leak by checking to see if the boiler is warm and the absorber is hot. Another sign of a leak is the strong smell of ammonia.
Take apart the unit and repair a leak if found. It can be dangerous if the leak continues. However, if you cannot fix the leak in the coils you must replace the unit.
