Red face due to toilet plumber's error (3,5)

I believe the answer is:

hot flush

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'plumber's error' is the definition.
I don't know anything about this answer so I can't judge whether this works.

'red face due to toilet' is the wordplay.
'red face due' becomes 'hot' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'to toilet' becomes 'flush' (flush toilet is a kind of toilet).
'hot'+'flush'='HOT FLUSH'

Can you help me to learn more?

I've seen this clue in the Sydney Morning Herald.

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