Winterizing holding tank sprayer lines

After a trip south and returning to impending snow, the need to re-winterize presented a situation I have not thought of or heard discussed before. The lines to the holding tank spray nozzles are exposed under the chassis. After spraying out the tanks and disconnecting the water hose, I opened the individual valves and a bunch of water came out of the inlet. I did not think of this last year, so obviously there was not a problem. It made me wonder if more water was still in the lines to the tanks that could not drain due to lack of gravity. Thinking of using an air nozzle to blow into the tanks to clear the lines....any ideas, comments, or concerns? Wasted worry?

Dougn

The inlet fitting includes an integral check-valve which is supposed to keep water from running back out the inlet. Since this connects to the waste tanks, the check-valve is a safety measure to prevent contamination of your filler hose. Perhaps your check valve is stuck open now. This could explain why you didn't notice this last year. If so, you should consider replacing the inlet fitting. I had to do this last year. Replacement part cost about $30 and was easy to install.

But of course none of this answers your question. If the check valve is doing its job, it seems to me that the water remaining in the flush lines could freeze and bust the pipes. But I've never heard of this happening. I wonder why.

John

The inlet fitting includes an integral check-valve which is supposed to keep water from running back out the inlet. Since this connects to the waste tanks, the check-valve is a safety measure to prevent contamination of your filler hose. Perhaps your check valve is stuck open now. This could explain why you didn't notice this last year. If so, you should consider replacing the inlet fitting. I had to do this last year. Replacement part cost about $30 and was easy to install.

But of course none of this answers your question. If the check valve is doing its job, it seems to me that the water remaining in the flush lines could freeze and bust the pipes. But I've never heard of this happening. I wonder why.

John

I won't worry about a back-flow check valve, since I attach the garden hose and turn it on, then turn on the tank spray valves, then turn off the tank spray valves, then turn off the hose bib. No way tank water gets anywhere near the garden hose. And at least the lines can drain somewhat without a check valve.  I didn't even think of those lines last year and they did not do any freeze damage, probably because the lines are a flexible hose, but what about the fittings?

Yes, I think the flush valves were omitted from winterizing instructions as I couldn't find a mention of them after having an issue last March trying to flush. After taking the lines loose from the tanks and finding water in them I concluded the problem was with the check valves being jammed from freezing. Couldn't find any damage but they wouldn't pass water.  I was almost to the point of ordering more when I decided there was nothing to lose by trying a light tap with a center punch. It worked and they got a blast of air last year after the last flush when winterizing.

HMMM...
I was hoping to hear if more people either did something to winterize these lines, or never thought of it but never had a problem. Or had no clue as to what I was talking about.  Or possibly never use the holding tank sprayer system at all? Or is it that of the 135 views, only 3 are actual PC owners? I guess also that PC does not monitor this Forum or they would have responded. Seemed important to me...
Thanks to those of you who did reply.
Dougn

HMMM...
I was hoping to hear if more people either did something to winterize these lines, or never thought of it but never had a problem. Or had no clue as to what I was talking about.  Or possibly never use the holding tank sprayer system at all? Or is it that of the 135 views, only 3 are actual PC owners? I guess also that PC does not monitor this Forum or they would have responded. Seemed important to me...
Thanks to those of you who did reply.
Dougn

We've had our Phoenix for five years, been in serious multiple day freezes several times and shorter multi-hour freezes many many times. We never thought about those lines, never did anything to winterize them and never had a problem. We use the flush valves often and they still seem to work fine. We show no signs of leakage under the rig from them.

Phoenix does not monitor this forum in the manner you suggest. I believe they jump in if someone is being evil (we've had a couple seriously nasty people get on then get tossed off during the six or so years I've followed the forum). They may read it occasionally but it is an owners' forum and they don't really mess with it.

Reading some of the replies earlier, they gave me the impression that the fresh water used for the tank rinse is somehow connected to the potable water inlet?   My 2006 model 2350 has a separate hose fitting just for flushing... Or maybe the check valve that is referred to is in this separate fitting.. ?

If I am in freezing weather with the coach it means I did something wrong...    So winterizing has not even been on the radar.


@ 2Lucky - You think eBikes are off topic?  Go see the  2020 Ford E450 cutaway thread... it has gone to discussion on building green.    Intelligent people tend to wander...   

The water system changed in 2014 I think. My 2013 has fresh water fill opening on passenger side and separate hose hookup in macerator cabinet for the tank rinse function.

Newer models have a four-way switch in the macerator compartment so they can fill and flush from the same location.

The water system changed in 2014 I think. My 2013 has fresh water fill opening on passenger side and separate hose hookup in macerator cabinet for the tank rinse function.

Newer models have a four-way switch in the macerator compartment so they can fill and flush from the same location.

  Whoa... so there is a direct line from the black tank to the potable water inlet? 

And... the potable water hookup is in the macerator cabinet? AKA The Sewer Closet?!?!??!   (or maybe I read that wrong...just the valve is...)

Um... my oversight I am sure, but HOW is that a better idea?  I do lack experience in this  , but the few times we have dumped there has been a hose at the station that I hooked up to the flush inlet. Then used same hose to flush my 3" line and elbow before I put them away. When we are at a full hookup, I have a 10' hose just for tank flushing and hose rinseout. The potable water hose is *NEVER* close to or used for these duties. Seems like basic sanitary 'common sense'.

I certainly hope I am wrong, but with the 'new and improved' single water inlet, am I expected to connect the dump station fresh water hose to my city water inlet and then flush tanks? 

Our 2007 2350 model with macerator has the fresh water tank filler door on the passenger side, and the RV park water connection on the driver side, but located away from sewage management.  Inside the sewer management macerator area (behind that long horizontal door hinged upward) there is another water line hook-up dedicated to flushing out the waste tanks.  I believe every PC equipped with a macerator, but WITHOUT the fancy current day 3 or 4 way water valve thingy is setup the same way.

The fancy 3 or 4 way water valve was introduced in model year in 2016 or 2017.....right?  Does waste tank flushing utilize that 3 or 4 way valve?  Or do you have the extra water line connection by the macerator to flush the two waste tanks like the older PCs have?

Newer coaches with the 3- or 4-way fresh water control valve still have the completely separate holding tank flush lines, plumbed to a dedicated hose connector behind the flip-up door which covers the macerator dump hose. Tank flush lines are totally separate from any fresh water plumbing.

Newer coaches with the 3- or 4-way fresh water control valve still have the completely separate holding tank flush lines, plumbed to a dedicated hose connector behind the flip-up door which covers the macerator dump hose. Tank flush lines are totally separate from any fresh water plumbing.

   I am SO glad it was my misunderstanding.  Dad was an engineer, so I can see how some engineer had convinced PC that all could be done with one water inlet.    I feared it was so.

Sorry. That was my misunderstanding. I'm glad someone with the new valve corrected me. I had thought the same bad design thing. So, what are the four positions on the valve? Fresh water to plumbing (water hook up),  fresh water to full holding tank, and two more? One is probably off.

On my 2018 2552, exactly one year old last week, the positions on the 4-way fresh water valve are:
— “City Water” - pressurized flow from the inlet hose,
— “Tank” - fills the fresh water tank,
— “Dry Camping” - coach pump supplies water from the fresh water tank, and
— “Winterize/Sanitize” - for slurping pink antifreeze into the plumbing.

John

So, are everybody's tank flush hoses exposed to the elements, and therefore should be blown out or winterized, which sounds like something no one has thought of or done, and with no apparent damage? (And I thought I had serious ADD.)