Draining the fresh water tank

Our RV has been unused in the past 6 months &, before using it on a trip later this month, I would like to drain the small amount of water in the fresh water tank & refill it.  What is the easiest way to drain the tank?  Is there a valve to drain it that I'm unaware of?  Or, do I need to pump the water into the grey water tank & then dump that tank?

There is a Drain Valve.  Intended for those owners who live in more northern latitudes where they need to "Winterize" by drainiing systems.  The drain valve for the freshwater tank is at the tank outlet.  Look between the tank and the water pump.  You'll find a valve there.

The presence and location of the fresh water tank drain valve varies from one PC model to another as well as changes made over the years.  Our 2007 2350's drain valve is attached directly to the fresh water tank.  It is not associated with the primary plumbing system.  I open the outside storage compartment door and it is right there in plain sight through a mouse hole in the finish panel between the tank and storage compartment.

Our fresh water tank drain valve looks idential to this one.  It is ultra cheap, but it has been working real well for 16 years and counting.





In our particular situation, I back up our PC on the slope of our driveway (front facing downward) to drain the last of the water which isn't much, surely less than one gallon.

The drain valve is under the bed.  You need to extend the rear slide, remove the mattress and you will see the access panel cut into the plywood.  Reach your hand down inside the plywood to find the 1/4 turn ball valve.  Make sure the slide is out or you will have a flood inside!!

Greg:

Thanks for the info regarding location of the fresh water tank drain valve on our 2013 2910T.  I removed the mattress & located the box containing the valve.  I'm assuming the drainage valve is the brass one (picdture attached).  Probably a stupid question, but since I've never drained the fresh water tank, here it goes.  When I turn the valve the quarter turn (so it is perpendicular to the coach, do I turn on the water pump to empty the tank?  I turned it, thinking it was a gravity-fed empty, but obviously nothing happened.  So, I figured I'd contact you before doing anything else.

Thanks,

Bruce Clerico
Orlando

No need to turn the pump on it should drain. The new to me Phoenix cruiser when I drained the tank last week did not want to drain even though the valve was open. I ran a wire up the tube and that did nothing I blew compressed air in the drain hole And that opened it up. Good luck.

Thanks for the info.  Just curious, where is the "drain hole" on your 3100?

Bruce

The valve in the 3100 is under the passenger side bed.

The location of the Fresh Water Tank varies.  Even among the same exact model - depending on year,  I have a slideless 2350 with the tank under the front of the bed.  From pictures contributed to this Thread, I see another member's slideless 2350 with the tank located under the rear of the bed. 
While the four foot difference in forward/aft location changes weight distribution that affects center of gravity, it also changes drain valve placement.  The drain valve access in my 2350 is in the rearmost corner of the storage bay and very awkward to manipulate. I have to literally crawl into the storage compartment to operate the Drain Valve.  The alternative, for better grasp, would be to reach the valve from above, by removing the mattress and plywood cover of the bed frame.

The location of the Fresh Water Tank varies.  Even among the same exact model - depending on year,  I have a slideless 2350 with the tank under the front of the bed.  From pictures contributed to this Thread, I see another member's slideless 2350 with the tank located under the rear of the bed. 
While the four foot difference in forward/aft location changes weight distribution that affects center of gravity, it also changes drain valve placement.  The drain valve access in my 2350 is in the rearmost corner of the storage bay and very awkward to manipulate. I have to literally crawl into the storage compartment to operate the Drain Valve.  The alternative, for better grasp, would be to reach the valve from above, by removing the mattress and plywood cover of the bed frame.

I am one of those people with an early 2350 with the fresh water tank placed to the rear.  The tank-drain is very conveniently located.  As you say, there are so many variations.

My freshwater tank did not want to drain when the valve was opened. I stuck a wire up it from the underside and had no luck. I did give it a shot of compressed air and whatever it was holding everything back moved and it drained fast.

My freshwater tank did not want to drain when the valve was opened. I stuck a wire up it from the underside and had no luck. I did give it a shot of compressed air and whatever it was holding everything back moved and it drained fast.

That is a great tip!

It is plastic scraps from when the factory drilled holes into the tank to install the filler tube, the vent, the pump intake, and the main drain.  I wished the factory made a better effort in cleaning that stuff out.  I found lots of tiny bits of white plastic scraps in my two low-point drain valves when I replaced them.  It explains why they were always so hard to close until I finally broken them.  My replacement ball valves are flow-thru which encourages discharge of such debris.  I wonder where else the scrap plastic bits are floating around in our PC.

Here are my original broken low-point drain valves.  I didn't think of taking a picture of the significant accumulation of plastic bits.

The original valves has the water turning sharp corners where the debris gets hung-up on and then piles up.


Here are the placement 1/4 turn flow-thru ball valves.  If replacing yours, I recommend buying this type.  I recall buying mine at Home Depot.

The free-flow ball valve design allows plastic bits to pass through and get discharged.

Seems like drill shavings plugging the water supply line is a common problem.  The first Phoenix Cruiser I purchased had a mere 12,000 miles.  I think the prior owner decided to unload it rather than undertake what some repair shop might have quoted as an extensive project requiring the Base Cabinets be removed to access the plumbing.  The unit was in pristine condition, and everything worked - except the water.  My prepurchase inspector focused on everything except freshwater flow. I didn't realize a problem until well after taking possession and about to embark on a trip when I found the sink plugged.

The fix was as described.  Remove the Block Valve and witness an impressive flow of white plastic detritus.  Reassemble the valve and enjoy water pressure. 

Actually, an easy job on the 2100.  The rear kitchen design placed the water tank under the sink cabinet.  Access was easy.  Water lines on my current 2350 are in an awkward position.  Rather than go to the rear corner of the Storage Bay, I presume the best route is from above thru the bed frame. 

I am wondering what others recommend as the best disassembly procedure.  The fittings are a right-angle connection firmly mounted in the floor and wall.  Is the procedure as disconnecting the upper line firts?  I presume the draine line can then be lifted.

Taildragger,

Your 2350 is setup differently than our earlier design, but maybe my experience will apply with your low-point drain valves.  As I recall, after I detached the valves off the floor from the caulk, I lifted them, detached the drain tubes to the street, then was able to pull the valves a few extra inches away from the wall to replace them.  I already had the crimping tool and bag of copper rings when repairing our PC kitchen plumbing, an unrelated problem created by my own doing some years earlier.

This is the crimping tool kit.  It worked well.

Thanks for sharing the benefit of your experience.  As I think about installing the new valves, I wonder about getting the factory existing parts removed.  With the right-angle bend in the mating parts and ample caulk, there is no free play.
The hardware store in the town where I store the RV offers to loan the PEX Crimping Tool.  I am confident about using the special tool for crimping connections.  Gaining enough longitudinal movement to allow replacement parts to be inserted had me supposing the entire tubing length might need sacrificing.