回复：Thanks jy101 and 瞎兄，sorry my question wasn't clear, let me tr

Both my air handler and condenser work now, but it's about 20 years old, and we I turn it on, sometimes it will not on, have to wait for a few minutes then try again. Since it's old, I am afraid it can die anytime, might worth to change a new one. My air handler is in my masterbathroom's top, only has 5 feet by 5 feet space. The contractor told me you can leave the air handler as is until it dies, but only change condenser for now. It doesn't need to be the same brand for air handler and condenser, he will replace with a new one with 3ton should be fine. My question is: is this true? should I do anything now or just wait until it dies. Thnks so much for your time and help!