City Water Port Winterization

[Dexter Adams]

2019 LEII. Have completed Oliver winterization procedure to the hand pumping of antifreeze into the city water port. Hand pump works fine but the connected CW  port refuses to accept antifreeze. Wash station cold faucet is on and on at handle. Have double checked valve configurations. Applied enough force to cause house to separate at connection. Could this be a stubborn check valve not opening at low (hand) pressure? Have not yet proceeded to fresh water and wash out ports. Thank you

[jd1923]

@Dexter Adams

Do you have a faucet open? I use air vs. antifreeze, but know that at least one faucet needs to be open, otherwise the plumbing is pressurized!

Don’t need faucet open for the Fresh Water line since tank overflow is always open.

Edited November 4 by jd1923

[Steph and Dud B]

33 minutes ago, jd1923 said:

Do you have a faucet open?

 

1 hour ago, Dexter Adams said:

Wash station cold faucet is on and on at handle.

This is an odd one. @Dexter Adams Have you had any problems with city water pressure while camping this season?

[Dexter Adams]

As a matter of fact city water pressure has been noticeably low, especially at the kitchen faucet. The toilet flush hasn’t seemed very vigorous either (I use standard brass pressure regulator at campground standpipe connection). The trailer city water connection itself was loose and leaking last trip, which I was able to stop by tightening the built-in 1/2” hex. Could too much torque on this cause an issue? Anyway, for now I was able to complete the winterization and (slowly) pump the antifreeze into the port… the fresh and washout ports flowed as they should. I will check valve settings again (exercise them?).  I’m still relatively new to Oliver but the system is behaving as if there is a restriction & that needs to be addressed prior to dewinterization & reuse. Appreciate the feedback.

 

[jd1923]

3 hours ago, Steph and Dud B said:

 

This is an odd one. @Dexter Adams Have you had any problems with city water pressure while camping this season?

Yeah thank @Steph and Dud B, I missed that he had the "wash station cold faucet" turned on. I guess that means the outdoor shower? I would try it again with the kitchen sink faucet on, handle centered both hot and cold, just to be sure.

If all fails, I suggest blowing compressed air though it! 😎 

[Steph and Dud B]

3 hours ago, Dexter Adams said:

I was able to complete the winterization and (slowly) pump the antifreeze into the port

Ok, that sounds better. There is significantly more resistance when I pump antifreeze through the city water port. It goes, but not real easy.

[topgun2]

Is it safe to assume that you didn't forget to also pump a bit of anti-freeze into the black tank clean-out port?

Bill

Edited November 5 by topgun2

[jd1923]

18 hours ago, Dexter Adams said:

As a matter of fact city water pressure has been noticeably low

The City Water plumbing in our Oliver consistently has lower pressure/volume than using the water pump and Fresh Tank (though we do have an upgraded variable-speed water pump). In a way it's neat that when we do not need much water, City Water gives us just that (water savings) and when we want better pressure we turn the water pump on at the same time. This works to supply extra water pressure and volume!

I have it on my long list to remove the water restrictors in both lines and remove and clean and/or replace the backflow preventers (check-valves). Not sure how your 2019 is plumbed, but you can start by looking here to see what you have and decide what to do. Look closely to see we have BOTH check-valves AND water restrictors on BOTH City and Fresh water lines.

[FloraFauna]

On 11/4/2025 at 5:12 PM, Dexter Adams said:

and (slowly) pump the antifreeze into the port

I am not having a problem but I did note that this is the slowest part of the winterization process.  It DOES pump slow.  That said, I rarely use my city water hookup.

[Geronimo John]

On 11/6/2025 at 4:07 AM, FloraFauna said:

I rarely use my city water hookup.

I have yet to use my city water hookup.  Fresh water hookup and boondocking ports are my preference as I control peak pressure to the system with these.  The city water hookup is a gamble as the city water pressure can be very high.  Sometimes dangerously high to our plumbing.  So that's why I don't feel the need to "Feel Lucky"!  

When winterizing, I also find it more difficult to get the RV antifreeze into the city water hookup unless I remember to "vent" the system: 

• Opening the exterior shower valve and it's handle latch helps just a little. 
• Removing the exterior shower head helps a bit better. 
• Opening an interior cold water valve works even better.  

GJ