The Thetford C220 removable waste cassette has its own blade, seals, vent fittings, wheels and transport parts. This illustrated parts reference separates those tank components from the C223-CS toilet body and flush controls. Use the original numbered drawing to locate each item and match the manufacturer reference before ordering.
C220 cassette components by service area
Blade and inlet sealing
Blade, opener, cover, retainer and lip seal
Spout and vent fittings
O-ring, pour-out spout, measuring cap and vent groupings
Rolling and handling
Wheels, axle, latch, handles and float arm
Thetford's diagram uses numbers 1–23 around the removable tank; those numbers are unrelated to the C223-CS toilet-body drawing's 1–10 callouts.
Thetford C220 waste-tank exploded parts list
The numbers below follow Thetford's tank-specific 2020 spare-parts sheet. A repeated part number may describe a multi-piece service group, not separate units sold individually.
| No. | Tank part | Thetford no. | What the number covers |
|---|---|---|---|
| 1 | Wheels (pair) | 200640 | Wheel-and-axle service grouping, refs. 1–2 |
| 2 | Axle | 200640 | Same 200640 grouped reference as the wheels |
| 3 | Tank-lock clip | 23849 | Clip securing the cassette in its installation |
| 4 | Transport-handle grip | 200966 / 200965 | Grip listed separately; also included in handle grouping |
| 5 | Transport handle | 200965 | Grouped with grip at ref. 4 |
| 6 | Transport-handle bracket | 200968 | Bracket associated with transport assembly |
| 7 | Tank blade | 50731 | Moving blade at waste inlet |
| 8 | Blade opener | 200970 | Mechanism for operating tank blade |
| 9 | Float arm | 200971 | Waste-level indicator linkage |
| 10 | Carry handle | 200972 | Separate carry handle on top of tank |
| 11 | Pour-out spout O-ring | 200973 | Grouped with spout at ref. 12 |
| 12 | Pour-out spout | 200973 | Spout and O-ring grouped service number |
| 13 | Measuring cup | 200967 | Pour-out cap / measuring-cup component |
| 14 | Automatic vent | 23722 | Automatic vent service grouping, refs. 14–16 |
| 15 | Vent foam | 23722 / 23788 | Associated with automatic/outside-vent groupings |
| 16 | Vent seal | 23722 / 23788 | Shown with both vent service groupings |
| 17 | Outside vent | 23788 | Outside-vent service grouping, refs. 15–17 |
| 18 | Sliding cover | 50718 | Removable cover for tank's blade area |
| 19 | Retainer seal | — | No individual order number in Thetford's table |
| 20 | Waste-tank lip seal | 23721 | Lip seal around the tank's inlet opening |
| 21 | Vent button | 07524 | Vent-button service grouping, refs. 21–23 |
| 22 | Vent spring | 07524 | Grouped with vent button and seal |
| 23 | Vent seal | 07524 | Grouped with vent button and spring |
Complete cassette versus seal or vent repair
Thetford's older C220 waste-tank sheet lists 200977 for the complete standard cassette and 200978 for the version with an outside vent. Its later C223-CS toilet-body sheet specifies 20097706 for the complete C220 replacement tank. Those document revisions should not be treated as proof that all tanks and vent versions are interchangeable.
The complete C223-CS toilet is Thetford 200866SP; it is not the same product as the separate 20097706 cassette.
Verified C220 seal in the NewRVParts catalog
The following listing has the exact Thetford 23721 number from callout 20. It is a sealing component only, not the complete removable cassette. Check the product listing for current supplier-warehouse availability; items cannot be viewed or picked up at NewRVParts.
Manufacturer exploded drawing and numbered key
Open Thetford's original numbered tank exploded view and the 23-callout manufacturer's parts table. The drawing identifies individual component positions, and the following page shows the part-number groupings.
The separate Thetford C223-CS parts sheet identifies the newer complete tank reference 20097706. Use the tank label and the correct manufacturer's service drawing to confirm the version.