Odors in RV
Battery boiling due to being overcharged/low water level....happens when on AC power source and not so smart converter/charger OR bad battery cell
Fridge......ammonia leak. BUT fridge stops cooling when that happens
Sewer/septic/waste holding smells........toilet bowl not holding water
Air Admittance Valve(s) not sealing (installed on sink drain lines after 'P' traps --- inside sink cabinets)
Sulfur smell........hot water heater -----stagnant water/high iron-sulfur connect water, high bacteria in water, magnesium anode rod