Toller

EVERY extended parts warranty and Parts and Labor warranty that I have
ever seen or sold REQUIRES regular PM to remain in force. If you have
a major failure of your car and you have no PM records the warranty may
be voided. Same thing with heat pumps and ACs. You probably need to
check it at least once per year. Every other year would be better than
nothing. Your heat & AC probably runs more than your car, you should
take as much care of it as you do of your car.

Stretch