No Heat

I am new here but have been reading the topics everybody has been posting but the one that concerned me is the "No Heat" topics.I decided to try one of the cures somebody posted about flushing the cooling system with Prestone and run for 5 hours and then fill it with more Prestone but keep it in there for a few days, drain it and then put the green antifreeze in it. Well let me tell you, I did this about two months ago and after 3 heater cores and I don't remember how many acid flushes the dealer did, I have more heat then ever before. The dealer would put in the heater core or the acid flush and I would have heat maybe for 2 weeks, but I am going on two months with heat. I would like to thank whoever posted that solution and would tell anybody with no heat to try it. You'll have heat from now on.