All depends on how your facility is wired. I can tell you that in our case, we want the water pump & furnace to run, but not the air compressor. They're not in the same buildings. However, the building that houses the air comp, also provides electricity to the fuel pumps. So, in the 2-3x annually that power "blinks" vs the real thing, I or someone will make that trip over to that shed to find out just "why" we don't have air supply & re-energize it. Not everything is possible from these isolation panels. But, for a relative few dollars & only basic understanding of electricity & circuits, you can make that relay system work.