….and if the condensate water valve is ok , i’d be looking at a blocked condensor box . Good luck with that because it can be a pig of a job…..mainly getting the lower hose back on properly. If you do have to take it off , make sure you check round the back of the hose to ensure its fully on ( A mirror is the best thing ) It may look like its on fully but don’t be fooled 🙂
To be honest Ally , its the removal and fitting of the condensor box thats the pain . Ordering a new box doesn’t help at all if its blocked , as it’ll just need cleaning out.
There are a couple of screws that are a bit of a pain to get to and normally its the refitting thats the real PITA !!!