Why does our jobsite porta potty reek of ammonia when it's cold?

Ammonia smell in a cold standard unit is normal once nights drop below freezing. The blue liquid can still look fine while the fragrance package goes flat and urine off-gas hits you the second the door opens.

Cold slows the tank chemistry that keeps waste smelling like product. Urea still breaks down into ammonia, and without a strong deodorizer mask that sharp note is what you get. Placement on level gravel with truck access fifteen feet out is not the problem. This is charge strength and service timing, not a bad pad.

For a crew of fifteen on a weekly service visit, call the operator and ask for a pump plus a fresh winter charge, or add a midweek stop until overnight lows ease. Do not dump random household cleaner into the tank. Tell them what you smell and when it started after the freezes. They see this every November and can reset the unit faster than waiting for the next scheduled run.