Hi guys, I'm hoping somebody could shed some light on a heater issue I'm having with my 2014 Seat Leon Fr 2ltr diesel. It's done about 58,000 km (not miles) since new. The heater seems to have lost its ability to produce heat. Initially, just before the issue appeared, I noted some weird noise coming from the heating unit before the heat went. I've played around with it and still nothing. Have checked the coolant in the tank (cant really tell the tank level when it's cold), but when the car heats up the coolant expansion tank is within the recommended level. Was also driving today with the AC on and noticed a noise (as if something was boiling) coming from the climate control unit/ vents. Any ideas / advice really appreciated. Have a yearly service booked in 2 weeks from now, so will get them to hook up the diagnostics if it isnt solved by then..