VauxhallI nsignia 2016 1.6 Vx line nav Diesel

[Gingerkev]

I’ve had a problem with no heat in my car, recently I had the radiator replaced due due an overheating problem and blowing a hole in the radiator. Still no hot air through the in car heater, had the heater matrix replaced as was told by putting rad weld In could have damaged it. Still no heater after replacing it and now had the heater sensor replaced but still no hot air through the heater.  Anyone know what could be causing this???

[Finn]

Thermostat?