Did you drain and rinse the fresh water tank? Assuming you might have put antifreeze in there.
It wouldn't hurt to connect a hose to the washer connections and flush them out also. Did you also flush out any outdoor shower faucets?
One thing I do that really helps get the antifreeze smell out is use bleach to sanitize the system after rinsing it out. I connect my hose to the trailer to fill the onboard tank. Before hooking the hose up to the spigot I pour a cup or so of bleach into the hose. The hook up the hose and fill the tank. Run each faucet until you smell the bleach. You also want to fill the water heater with that solution so run plenty through the hot water taps. Then let it sit for the night before draining everything again. Run fresh water through for another rinse and you should be good to go.
