So I recently replaced my expansion tank, along with various hoses. Now, I seem to have an issue with the heater. No hot air seems to come out of the vents. It blows semi warm air from drivers vent, and that's only for a few minutes. Won't blow warm through passenger vents at all. After a few minutes, it stops blowing warm air through drivers vent. What the hell is going on? It was working fine before my expansion tank started leaking. I bleed the system properly before anything.
I don't see what else could be causing this. Does anybody got any ideas to what could be causing the problem ? Used to blow hot air just fine.
Update Solution: Heater Valve Failed. Rubber gasket seals inside heater valve started to deteriorate. Replaced heater valve and problem solved.
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