My Designer had a PD9280A converter/charger in it when I bought it new. After 8.5 years of full time use it started having issues. I thought I had a slide motor problem when my big slide was struggling coming in or out and my batteries were both new (Trojan T105's). What I found was the PD9280A was only putting out 11.0v and both batteries weren't fully charged. I replaced the PD9280A with a new one and problem solved. The PD just slowly started putting out lower voltage and I never actually check the battery voltage which was lower than it should have been for 2 fully charged batteries. All is good now.
2006 GMC 2500HD CCSB 4x4 Duramax/Allison, Titan 52 gallon fuel tank, Prodigy Controller, B&W Companion Hitch
2010 Jayco Designer 35RLTS, Cummins/Onan RV QG 5500 EVAP, Progressive Industries EMS-PT50X, TST Systems 507 TPMS, RV Flex Armor Roof