The Water Heater Bypass is used when winterizing the water system. It is a series of valves or a single lever valve that allows the water flow to be shut off from the water heater and still be pumped to the rest of the hot water piping
. This eliminates the need to fill the water heater tank with 6 gallons of winterizing antifreeze ... the tank is bypassed and then drained of water.
The water heater bypass valves are the majority of the time located directly behind the water heater on smaller travel trailers. This will require you to gain access to the valves from usually inside the trailer. You may have to remove a false cabinet panel, remove drawers, look under a bed, etc. to gain access to the valves. Maybe someone with your particular RV will chime in with the exact way to access the valves.
If you have the three valve system, you will want the handles turned for normal use liike in this pic. The cold water inlet valve is open, the hot water outlet valve is open....and the bypass line that goes between the hot and cold water lines has it's valve closed.
Originally Posted by Rodski
I assumed when you fill up the tank it would automatically flow into the hot water heater but that does not sound like the case. Any one know?
When you say "fill up the tank", I am assuming you mean the freshwater tank? If this is the case, you have to turn on the water pump to get water from the "tank" to the water heater for it's initial fill... and/or to the taps.
If you are connecting to a constant city water supply (no tank), then you won't use a pump and the water heater will fill up (if the bypass valves are set correct). You may need to purge the air out though as it's filling.