I grew up in a house that used a well for water. From my earliest days traveling in RVís I never understood why the pump had to run all the time when you used water. It doesnít in the house because of the pressure tank.
So I decided it was time to install one in the motorhome. I looked at the shurflo expansion tanks but they're tiny. What's the point of putting one in if it only holds a few cups of water? After doing some reading and taking some measurements I decided to use a 5 gallon water heater expansion tank. That should give me a about 2.8 gallons of pressurized stored water.
Install was a snap. The attached pictures will show how it was done. The only thing wrong is that I have no way to drain the pipe the runs under the storage compartment. But I just plumbed it in with the parts I had on hand. Iíll probably replumb it slightly moving the low point drain down several inches and adding a pressure gauge just for fun. I might add a shut off valve also so I wouldnít have to fill the pressure tank with antifreeze if I decided to winterize that way.
After the install I tested it out. Once the pump had been on for a while and charged everything up I shut off the pump switch and opened the kitchen water faucet. Water flowed and flowed, for a lot longer than I expected. Iím defiantly getting my 2.8 gallons worth out of it. Enough to fill my largest cooking put without the pump ever coming on. Since it worked so well I decided to leave the factory 35psi of air pressure in the tank bladder.
2008 Georgetown SE 350DS BunkHouse