One of the greatest secrets to how our central heating and A/C system is still running strong after almost 22 years is one thing. That one thing is the fact that I keep up with our heating and cooling system tune up and check ups. I have the local heating and A/C system company send out a certified heat and air conditioning system specialist to do Heating, Ventilation and A/C tune up and check ups on our central heating and A/C system once at the beginning of every season change. That is once in the Winter season, once in the Springtime, once in the warm season and last but not least, once in the fall. By having the heating and cooling company send out someone to do a check up and tune up on our central heating and A/C system at the beginning of the seasons, it makes it so that our central heating and A/C system machine will keep on running. If there is even the a small fault with our Heating, Ventilation and A/C system, the local heating and A/C system specialist from the local heat and air conditioning system company will identify it plus then repair it while in the heating and A/C system tune up plus check up that I get. And I have a really nice heating and A/C system company and a superb heating & A/C system all together. Tha is the secret for our central heating and A/C system lasting for 22 years. And we do not see it failing any time soon.