Is the tap quarter turn? That immersion heater is dangerous, it should have a cover on it.
Edit: Your hot water outlet from the cylinder appears to be rising, could be causing an airlock.
Firstly, I'm afraid whoever fitted that was not a Plumber, classic giveaway of PTFE tape on compression joint threads for starters. I'd be checking there wasnt any debris blocking the hot supply before doing anything else.
Secondly, the Immersion heater has live terminals exposed, you must get an Electrician to look at it and make it safe. Edit, Chris has already spotted the immersion.
The isolator valve for the flexi just to the left of the waste pipe looks to be half closed. Is that the feed for the hot water?
but if there was an airlock, I would have the same problem in the bathroom sink no? Bathroom sink works fine, i get hot water there.
Yes, you would. Trying to help rule out, but I’m sure you would have posted this information
That's a high pressure tap.
Andy
How do I check if there is debris blocking the hot supply?
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