I have a greenstar 440 displaying d5, I have tried the reset code ?
using service mode , eco button and Cs but it will not display 5a I get every other code eg 1a up to 4f then goes straight to 5b then back around and so on. I've made sure condensate trap and pipes are clear and cleaned out condensate pump but still can't get to 5a to reset , I have noticed I don't get green light on condensate pump at any time. Could the pump motor of gone.
The condensate pump could've failed (could OF???). If you can organise it you could try diverting the condensate drain into a bucket and see if you can get some sense out of the ghing
You could also try feeding water into the condensate pump inlet and see if that starts it.
Phgs
July 2020
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