A lot of misinformation and half truths on this thread. The WFCO as installed by most manufacturers does perform poorly as most posts indicate. If it is installed close to the batteries with adequate wiring it will indeed perform to its designed specs.
Here is my experience after moving the WFCO from under the fridge, 30 wire feet away from the batteries and connected with #8 wiring to a location just above the batteries and connected with large wiring.
Link to WFCO modI did not record the voltage during the post mod testing but it responds as ktmrfs describes in this thread.
It outperforms its rated amperage 65a vs 55a.
It will remain in boost (constant current) for 4 hours if battery bank will accept it.
It will revert to float if the electrical system is undisturbed for 48 hours.
To the OP, based on the results you are getting I wouldn't recommend replacing the WFCO.
