We found our converter behind the water/winterizing/waste Mgt. control panel. Not at all what I expected considering all the water connections in that area.
We had the same problem with our converter...lights dimming etc. If you take the converter out to test it, make sure you test it under a load. The WFCO WF-9875 originally tested with the correct voltage, but after loading the converter with a 12V DC load the converter could not regulate the voltage properly.
We replaced our WFCO with a Progressive Dynamics PD9280AV, which is an 80 Amp 1300 watt converter. We are very happy with the product