I have a goodman a49-20 heat pump. Outside unit and oustide fan are not running. Have replaced sequencer on inside unit. Also replaced the defrost board and contactor. Capacitor is new too. Any ideas?

Does the contactor pull in? If not :
When measuring at the defrost board, do you get 24 volts between Y & C, and O & C?

If the contactor is pulling in: What voltage do you have across the incoming line voltage terminals on the contactor? How about on the out going terminals?

Thanks for the quick response. I don't have anything to measure the voltage, so I am not sure.

Can you tell if the contactor is pulling in?

I don't think so. After I replaced it, it does not seem to be doing anything. I also replaced the outside circuit breaker yesterday. The unit does not seem to be getting any power.

You need a voltmeter to do any testing & troubleshooting. We can throw parts at this thing all day long & spend a whole bunch of money only to find out there was a broken wire in the low voltage system.

Yes, you are right. I need to get one. I had someone check last night and I an getting power to the outside unit. The Freon was completely out meaning I have a big leak. We're going to try and find it, but if it is in the air handler coil, I will probably need to end up replacing the whole unit rather than spending a bunch on a 15 year old unit. I appreciate your help and advise.

With a 15 year old heat pump, I wouldn't waste the time trying to find a leak which, if in one of the coils, in all probability isn't going to be repairable anyway.
The new R410A heat pumps do a far better job of heating than did the R22 units.