RV Black and Gray Tank: Dump, Maintain, Repair

Black tank maintenance

Task Action Stop
Before travel Dump the black and gray tanks before traveling. Stop if the tanks are full and no dump station is available.
Valve timing Keep the black valve closed until the tank is at least 3/4 full. Stop if the valve leaks.
Deodorant Add deodorant after dumping and before use, unless winterizing. Stop if the tank is frozen.
Dump order Dump black first, then gray, to rinse the outlet and hose. Stop if the hose leaks.

Gray tank maintenance

Task Action Stop
Dump order Dump gray after black. Stop if the gray valve will not open.
Level and station Level the RV and use an approved dump station. Stop if no approved station is available.
Hose Remove, clean, and store the sewer hose; close the dust cap. Stop if the hose is damaged.
Leaks Check all waste fittings for leaks before each trip or storage. Stop if a fitting leaks.

Black tank repair checks

Check Action Stop
Waterless trap Remove the waterless trap before using mechanical drain-cleaning devices. Stop if the trap is damaged.
No-drain branch Check that the dump valve is fully open and the hose is not blocked. Stop if the valve is damaged.
Leak Stop on a leaking waste fitting or damaged dump valve. Stop and use qualified service.

Source: Jayco 2025 Class C Owner’s Manual

Related RV owner guides