Waterco Trimline Cartridge Filter Air Release Valve - MkII and MkIII - 620221

Waterco Trimline Air Release Valve - MkII and MkIII

Genuine Waterco air release valve, part number 620221. This is the small bleed screw in the filter lid that lets trapped air out of the tank. It is the first thing you open before removing the lid, and the part that lets you purge air after starting the pump.

Replace it when it will not seal after closing, when the thread has stripped, or when the valve weeps continuously. A leaking air bleed is also a common reason a filter will not prime properly, since it lets air back into the tank.

Specifications

Part Number	620221
Manufacturer Description	Air Release Valve
Brand	Waterco
Fitted To	Filter tank lid
Quantity Per Filter	1

Fits

Waterco Trimline cartridge filters, MkII and MkIII — C25, C50, C75, CC50, CC75, CC100, CC150.

Fitting

Shut the pump down and make certain the tank is at zero pressure before unscrewing anything from the lid. Do not overtighten on refitting — these thread into plastic and the lid is far more expensive than the valve. If the o-ring on the valve is perished, replace it at the same time (620193, or 6201931 in Viton).

Related Trimline Parts

• 620193 — Air release valve o-ring
• 6201931 — Air release valve o-ring, Viton
• 62026 — MkIII lid o-ring, 214mm
• 62021 — MkII lid o-ring, 221mm
• 62024BLK — Lid lock ring

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Manufacturer Manuals, Diagrams & Part Numbers

Need exploded views, spare part numbers, diagrams, or more product information? See Waterco's Trimline Cartridge Filter manual.

Important Before Ordering: Please ensure you order correctly. Confirm this product is suitable before ordering. Use the manual above, seek professional assistance, or contact us with photos of your existing part, model details, serial numbers, and any labels.

As with all products, these must be diagnosed and fitted by a qualified and experienced person.

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