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You have two types of aerators, one with a non-return valve and one without a non-return valve, the aerator without a non-return valve will then have a hose attached to the aerator that then leads outside and water will continuously flow out when the engine is running.

Aerators with non-return valve.

Aerator without non-return valve.

Aerator with non-return valve in parts.

Check aerator.

The aerator with the non-return valve must be cleaned at the beginning of the season and checked for correct operation. The only way to check this is to take the aerator apart.

Please proceed as follows:

1 Remove the top of the valve body.
2 Carefully remove the valve and clean it thoroughly, this also applies to the seat on which the valve closes
3 Check that the aeration pipe is clean by blowing it through.
4 Put everything back together carefully.

Tip: To perform this job it is better to take the aerator off the rigging and disassemble the hoses and then disassemble the aerator upside down.

If you need an aerator, you can find it on this site with this link.