Central air probem?

Question

suddenly our central air does not work. the unit does not kick on, nor does the fan. We also have forced air heat and that does not work either. What should we check, and any ideas what it might be?

Answer 1

sounds like no power supply, since none of the units work it would have to be a circuit breaker or switch that controls all of them,also could be open circuit in wiring, you will need a volt meter to trace the problem, start at main power supply at circuit breaker box, then check power at furnace where main relay station is to the rest of the system,if you have power at the furnace then depending on what year you have-the newer units have circuit boards that ussually fail,the older units have contactor relays that burn out,or the problem is in the low voltage side meaning that it is the transformer or thermostat circuit, check voltage on both sides of the transformer, one side should be line voltage[120 or 220 volts] and the other side should be 24 volts, if you have line voltage but no 24 volts it is the transformer windings burnt out,which happens alot on older units,cuircuit boards on the newer units are are the most common problem, transformer cost around 20 to 50 $, circuit boards start around $100, either one are not that hard to replace, if you have power at the breaker box and not at the furnace there is an open wire, or bad connection somewhere inbetween the the two

Answer 2

Have you tried the circuit breaker panel?

Is there power to the indoor and outdoor units?

Have you changed the filter? (low air flow can cause the unit to quit).

Are there any breakers or fuses in the unit itself that you have not checked?

If you don't know how to check for power, call in a reputable service company that has been in business for more than 10 years.

Keep Kool

Answer 3

many thing to check < #1 is the disconnect switch in ? #2 hav you switched tour thermostat to the cool position ? #3 do you have a digital thermostat ? And when did you if you have one replace the battery last . #4 is the breaker in the fuse pannet for the air conditioner in the on position ? theas are the simple things you can check before you call for service to come to your house.

Answer 4

first check to make sure that your circuit breaker is not tripped,than check your thermostat make sure it is on cool and not set very high.it sounds like a power problem.