Code f- 18 means filter blocked. Filter is clear, detergent solution pump is clear and moving freely, pipes are clear. What else can be making the f-18 code come up when everything has been checked and rechecked? Occasionally a wash will go through without stopping.
Possibly pressure switch intermittently not deactivating when drained out . Trace small hose from pressure down to air collector chamber and check chamber is not blocked with sludge. Also blow down hose from pressure switch end to clear it.Cheers.
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