I would start with the troubleshooting steps in this document. Be sure to check the vents. If the steps there do not resolve the issue the post here may help. I would do the soak before I would buy a new printhead.
One thing to prevent this issue in the future - make sure you never power the printer off from an external switch such as a surge protector or a switch on an outlet. Doing so can leave the printheads out in the air which can cause them to dry out.