I'm helping an older lady with her 1998 Fleetwood Wilderness. We have it hooked up and the hot water heater is heating the water but the flow is very restricted to all faucets. There is a single bypass valve. If I turn on the outside shower which seems to be the first connection on the hot water line then the hot water will flow normally to all the facets. Could it be that there is something in the line at that junction that is blocking the flow but when the outside valve is open it is allowing the water flow past?