I have a York Stellar Central Environmental Heating/Cooling system installed in April of 1994. Model number is G/CN060SA. The unit sends strong vibrations through the floor when it is running, and occaisionally just makes a buzzing noise without generating any heat. I have found that by resetting the circuit breaker and turning the thermostat from on to off and back to on solves this second problem. Are these issues normal, or does the unit need service? What is the efficiency of this unit compared to a new furnace? Should I replace it instead of getting it serviced?

You might need some isolator pads installed under unit OR the blower motor and wheel could use some attention.