Just into my first house and trying to get to grips with understanding everything I need to be looking after.
Been looking into the central heating set up and the magnetic filter is covered in gunk around the pipe connection (pics attached). The gunk also has a sheen on it which rubs onto my fingers when it's touched making me think there's a leak in the isolation valves.
Is this expected and does it just need a clean or is it a sign that there's a problem here?