Question: Water system valves

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thelazyl

Well-known member
Joined
Nov 9, 2018
Posts
600
Location
Molalla, Oregon
Hello:  New RV owner.  I've read through all my available manuals and can't answer a basic question.  I attached a photo of my water system on my 2003 Fleetwood 37U.  In preparation for winter I drained the hot and cold water tanks.  I plan to push air through the lines next.

My question is about the bypass valve.  I am unclear on what it is designed for.  I tried following the water lines but no luck.  When the valve is in 1 position the water came through the tanks when I drained.  When I use the 2nd position no water came out.  Frankly, after fussing around with all valves I don't recall which position the bypass valve was left in.  Can you help on the purpose of the bypass valve - and under which circumstances I should use it?

I have a second question:  This RV is in excellent condition.  One of the exceptions are small areas of rush on the metal around the valves.  Should I be worried about this spreading?  Can you recommend a treatment - i.e. wire brushing and then spray paint.

I appreciate the patience of people on this forum.  I am getting excellent advice.
 

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The purpose of the bypass valve is to for the fluid to bypass the water heater when winterizing. If you winterize using the pink antifreeze, the valve will stop antifreeze from getting into your water heater. This will save you between 6 and 10 gallons of antifreeze depending on what size you have.

What are the words under the black tank flush fitting and the city water inlet fitting?
 
The words are "Hot Water" and "Cold Water".  I opened these 2 valves to empty the tanks.  As far as I can tell these are located at the low spot.  I see no other drains in the system.  There IS a "quick drain" on the other side and I opened that as well.

Thanks for your help on this. 
 
I have a follow-up question:  I don't have a hose or connector to suck in the pink stuff.  With our climate (Oregon's Willamette Valley) I've been told by friends it isn't needed if you blow out the lines.  I have a connector to push air through.  I plan to limit the PSI to 20 to protect the lines (sound about right)?

Is there an easy way to tell which position my bypass valve should be in for normal operation?  When I drained hot water and cold water - they would drain only if the bypass was in one of the settings.  And, I forgot which is which on the bypass valve setting.  My plan was to fill up again with water before our next trip and then experiment with the bypass value.  in other words, after setup at the park, if the wife is upset with no water then I try the "wife not upset" setting on the bypass valve.
 
THANK YOU!  This makes sense. I now recall reading that in the Fleetwood manual but it didn't make sense to me at the time. 
 
I can't help with the bypass valve, but blowing everything out with air is sufficient to winterize. I used to use anti-freeze, but folks here convinced me it wasn't necessary. I haven't had any problems since using just air. Make sure you take care of the outside shower, ice maker, and clothes washer if you have them.
 
thelazyl said:
The words are "Hot Water" and "Cold Water".  I opened these 2 valves to empty the tanks.  As far as I can tell these are located at the low spot.  I see no other drains in the system.  There IS a "quick drain" on the other side and I opened that as well.

Thanks for your help on this.

OK then those are your low point drains.
 
Laura & Charles said:
On our Fleetwood, there?s a valve in the wet bay labeled ?water bypass?.  When hooked up to city water, it bypasses the rest of the coach?s plumbing and fills the fresh tank.

That's different. I have a valve also that says "Water Bypass" but that's for bypassing the water heater when winterizing. The valve for filling the fresh water tank for me is labeled "Tank Fill". 
 
thelazyl said:
The words are "Hot Water" and "Cold Water".  I opened these 2 valves to empty the tanks.  As far as I can tell these are located at the low spot.  I see no other drains in the system.  There IS a "quick drain" on the other side and I opened that as well.

Thanks for your help on this.

Those are the low point drains that empty water from the plumbing lines in the RV, not the tanks.  You still have to manually empty the freshwater tank and hot water tank.

There's probably another drain near the freshwater tank to let you drain it.  You drain the hot water tank by removing the large bolt near the bottom of the tank.  It's on the outside access panel.  Then see if you have a Water Heater bypass valve and set it to bypass the hot water tank.

Now you can blow out the system with air or add antifreeze.
 
Welcome to the Forum!

The way I read your question, you are asking about the water heater bypass valves, used when winterizing.  Your picture is where water enters the RV.  Apples and watermelons!

HWH bypass valve (s) are usually located on the back of the HWH.  This is often behind a false back in a cabinet.  Locate the HWH on the outside of the RV, then go to the opposite side of that location inside the RV and look there.

Bypass valves allow water to flow in all camper faucets without going through the HWH.

Drain all water possible by draining the fresh water tank and opening your low point drains.
With fresh water empty, run the pump for a minute to drain / pump all water out of the pump.
Close low point drains. Connect your blowout plug to the city water inlet in your picture and go for it!

Just did mine this morning.
 
kdbgoat said:
I can't help with the bypass valve, but blowing everything out with air is sufficient to winterize. I used to use anti-freeze, but folks here convinced me it wasn't necessary. I haven't had any problems since using just air. Make sure you take care of the outside shower, ice maker, and clothes washer if you have them.


How do you get the water out of the pump? Who do you get the water out of the city water inlet back flow valve.
 
Last night I learned several things:  Where my water pump and filter screen are located; and where the ice maker water line is located.  It was a lot easier than I thought.  I am still fighting a perception that I will need to disassemble an entire RV to get to maintenance items ;).  Thank you to everyone that helped.

I have some follow-up questions.  Last weekend I drained the water tanks to practice for when I winterize (including water heater).  I put in a half-tank of fresh water using a water hose through the port.  I let the water pump run for ~5 minutes with a faucet on.  Water spit out and later I could feel air rushing through the lines.  I never got to the point where water would come out consistently.  Fresh water 86 gal.  Water heater 10 gal. 

1. How long does it typically take air to come out of the system before water comes out?
2. I experimented with the ?bypass valve? in my wet bay.  The water pump sounded different in each setting.  I wasn?t able to figure out where to leave the setting ? I left it in the spot where the pump sounded like it was grabbing water.  Does this valve have an impact on how water is pushed through the lines?  I assume the answer is yes ? and that I should have this valve in 1 setting when I have water hookup and another setting when I do not.  I attached a photo of my wet bay for reference.
 

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