Help! Antifreeze not being pumped in

BandB

We are trying to winterize our 2022 Tab 320S Boondock today. We're following the YouTube video that NuCamp put out recently. We blew the water out of the lines with our new air compressor. Put the Nautilus levers in the Winterize position, put the red Alde lever in the bypass position, hooked up a short hose to the Winterize port, put the other end of the hose in a gallon of antifreeze, turned the pump on (the switch inside the Nautilus) and... nothing. We can hear the pump, but nothing is getting pulled in. We tried filling the short hose with AF to help it get going, but still the AF wasn't being pulled in to the fresh tank from the AF jug. Appreciate any thoughts on what we should be doing. It's already cold here in MN. We snuck in one more camping trip while the weather was nice, but upon getting home we were hit with cold. Forecast is down to 32 degrees overnight.

Sharon_is_SAM

The pump needs priming.  After you fill the short hose with antifreeze, turn on the pump, then blow into the short hose and hold it up high.  If the pump starts to siphon, don’t let air enter, so quickly return the short end of the hose to under the surface of the antifreeze.

BandB

@Sharon_is_SAM, thank you for your suggestion. We did exactly what you said twice (I even printed out your directions), but nothing happens. Does the diameter of the hose make any difference? We're using a 1/2 inch hose.

pthomas745

This is one of the ongoing problems with this process of using the pump to draw up antifreeze. It works very inconsistently.   One owner filled the hose...and blew the antifreeze into the pump as it ran.  Other owners lift the bucket and shorten the draw the pump has to perform.

An owner on the FB page the other day...tried everything for two days.  And then re-discovered the Camco antifreeze adapter. 

https://www.amazon.com/Camco-36543-Converter-Winterizing-TRV874795/dp/B0006JJ588

Some owners have made their own adapters to connect to the pump. 

Sharon_is_SAM

@BandB - not sure of the diameter hose.  Make sure your pump filter is clean and the filter cup is tight to prevent an air leak.
Try keeping the pump off, add AF to the hose, then turn on the pump.
Here is a link with other ideas for priming the pump for Winterizing.

https://tab-rv.vanillacommunity.com/discussion/14407/winterizing-tab-400-boondock-2021-pump-problem/p1?new=1

BandB

@pthomas745 and @Sharon_is_SAM Thank you both so much for your input. We're going to hope for the best tonight and try your suggestions tomorrow. We have the heat on in the Tab and I put some AF in the toilet bowl, a little down the shower drain, and some down the KT sink. I'm so thankful for this forum! I would be lost otherwise.

BridgerSunset

@BandB - a few points:

By "short",  I'd suggest the hose be kept under 3 or 4 feet long; preferably a cut-off garden hose which I think are usually 5/8".   1/2" diameter could work.  But it needs to be made of a material rigid enough to resist collapsing from the suction power of the pump (like, don't use nylon).

And if there's any kind of crack or split or hole in the suction hose, the pump likely won't catch prime (kinda like trying to drink through a straw with a hole in it). 

And what @Sharon_is_SAM said regarding pump filter.

Is there any chance the pump discharge is up against trapped pressure somehow from the air compressor operation?  I don't do that, so not sure what the possibility is.

I assume you do have a faucet open somewhere in the camper when you're trying to get the pump going.  It helps.

pthomas745

Someone on the FB page tonight was told by "someone" to pull the screen out of the city water inlet...and their pump started to draw antifreeze as soon as they pulled out the screen.  I don't know what the screen looks like, or if it was a coincidence, or what...but it worked for them.

Sharon_is_SAM

I know there is a small screen on the ‘city water” inlet, but nit sure about the pump inlet.

pthomas745

And:  now it seems that NuCamp has a winterizing video out for one of the newer models that says to take he little screen out of the city water connection when trying to pump antifreeze.  So, it seems NuCamp knows this isn't working well for the Nautilus.

dsfdogs

@pthomas745 The most recent video is for the 400 and covers years '21, '22, '23. The screen is pulled out only for the air compressor blowout plug, then put back in for the antifreeze siphoning. For the 2023 320 video they show a hose connection to the fresh inlet for both the air compressor and the antifreeze siphoning process and the filter remains in place for both.

pthomas745

@dsfdogs Thanks for the correction and explanation.  I haven't been able to keep up with the FB comments this morning on this.  But....they are all off and running with "take the screen out to pump antifreeze."  So, thanks.

Other comments are pointing out they got good results with the pump using shore power compared to battery.  So, lots of ideas, and the learning never stops!

I'll actually watch the video after I have coffee.....

pthomas745

And.....the plot thickens.

Here is the Famous 400 Winterizing Video, which was posted just yesterday. (Oct 14, 2022).

https://www.youtube.com/watch?v=UN5CVaT9wHo

At 1:34, the screen on the City Water inlet is removed to blow out the lines.

At 2:10, the screen is replaced to add antifreeze.

In the 320 video, posted on Oct 14, 2022.

At 1:25, screen removed from City Water inlet to blow out the lines.

At 2:20, screen replaced.

Then they move over to the Winterize Port...the screen is clearly visible at 2:21....and no mention is made of taking it out. They happily pump antifreeze with the screen in.

https://www.youtube.com/watch?v=UN5CVaT9wHo

Horigan

This discussion makes me so glad the older T@bs without the Nautilus don’t require antifreeze for winterization. 

pthomas745

The newer ones really don't seem to, either, but NuCamp doesn't acknowledge the blow out method exists. 

BandB

Well, I think we got the antifreeze in! Thanks to all for your help. We ended up buying a longer funnel and a 5/8 inch garden hose plus we opened the sink faucet. Hopefully this goes easier next fall!
@Sharon_is_SAM, I must have started this discussion in the wrong place. The heading says "For Sale New/used trailers. Sorry about that.

Sharon_is_SAM

Thanks @BandB.  I moved it to a different category.

Buckster

pthomas745 said:

This is one of the ongoing problems with this process of using the pump to draw up antifreeze. It works very inconsistently.

Add me to the growing list of T@B owners who are continuing to encounter this problem. I am trying to winterize our 2022 320 and I have tried every suggestion –– elevating the hose and funnel, blowing into the hose to force the antifreeze into the pump -- absolutely NOTHING has worked. 

pthomas: I looked at the Camco antifreeze adapter from Amazon but after looking at all the hose lines on our 2022 T@B 320, I'm unsure which one to attempt to take a part in order to prime the pump.  I am also unfamiliar with the metal hose clamps nuCamp uses, how do they come off?

Honestly, I'd rather not take any of those lines apart.  The other thing I noticed is that the pump is mounted above (elevated) the inlet lines, making it that much harder to get fluid to the pump to prime it.  Does anyone else have any suggestions?  It's especially frustrating when I read in other threads that it appears that nuCamp is aware of this particular problem. 

pthomas745

@Buckster find your pump, and look at the inlet side of the pump.  The "three way" adapter connects there.  It just unscrews from the pump, the adapter screws in.  The video from Travels with Delaney below shows how they used it on their 2018 Tab 400. About the 3 minute mark. Your setup may look different, of course.

So, find the pump, take pictures if you need to.

https://www.youtube.com/watch?v=wU3YPMKm4iE&t=195s

Here is a thread showing the same trailer, but there are photos showing the adapter being connected directly to the pump inlet.

https://tab-rv.vanillacommunity.com/discussion/9946/installing-camco-winterization-kit-on-t-b-400

Yoshi_TAB

Hi @Buckster ,

I just winterized my '21 320 today with the Nautalis System.  I noticed when I had the the siphon in the antifreeze jug and turned the pump on first, nothing happen when all the faucets were closed.   Once I opend the kitchen or bathroom faucet, it immediate began to suck in antifreeze.  That may work ...

bjn2

My 2023 refused to siphon until I raised the level of the antifreeze jug higher than the hose connection in the Nautilus. 

Buckster

Thanks for the responses. @Yoshi_TAB that's what I ended up doing as well. I had tried everything else to no avail but when I opened the kitchen faucet, the pump finally began draw antifreeze.  There's a lot to like about the Nautilus system overall, but this is a significant issue that needs to be addressed and fixed.

BridgerSunset

By opening an elevated valve in the camper, you are allowing trapped air to escape the plumbing system.  Pumps don't like to pump air, and any air present in the system just gets compressed and then uncompressed within the piping system with every stroke of the positive displacement pump.  So there's no net fluid flow with every stroke, and the pump runs but doesn't actually move liquid.

I'm  pretty sure this failure to evacuate air in the piping is the cause of most frustrations in winterizing. 

pthomas745

Not disputing the "opening a faucet" trick, but, why does the antifreeze suddenly start to flow with everything closed and just by lifting the container higher than the city water inlet?  Why wouldn't the trapped air stop it in that case, too? 

BridgerSunset

Always it's necessary that these pumps are provided with their required "net positive suction head" (NPSH).   Different for every type pump.  This pump for example, per Pentair, is recommended to be installed within 6' of the supply source, presumably to insure a flooded suction.  If much further away than that, then friction losses in the suction line can cause the pump to push water away faster than it can enter the pump, and air is pulled in or cavitation results.  Lifting the container also uses height to satisfy the NPSH to prime the pump.

As for a closed system & simply raising the jug alone kickstarting things, I can only speculate that air is minimally present at high points in the piping, or is dispersed enough to not affect fluid-packed displacement.  Good question.

pthomas745

Gee. I love that kind of talk!  Thanks for that explanation.

Happy_Camper2

Ok, Tab friends, I have a Tab 320S Boondock 2021. Trying to winterize before the severe unexpected freeze here in Texas.  We were just going to make do with keeping it heated during lighter freezes but 9 degrees is a bit unusual here.

Anyway, I can't get the antifreeze to suck up after I blew out my lines.  I have tried everything I know: faucets open and closed, pouring it directly in my short hose...we ordered an RV hand pump antifreeze kit that arrives tomorrow (I hope this works but I'm worried).

Do you have any other suggestions?

manyman297

I know some have had luck filling your hose with antifreeze and blowing into the end to force it into the pump to prime it.

pthomas745

The FB groups are flooded with reports of "Nautilus won't pump antifreeze" this morning, during the Great Freeze of 2024.  No amounts of work arounds, opening valves, raising the bucket, filling with a funnel, blowing into the hose....has worked.  I wonder how much the viscosity of the AF changes when the temps get lower?  (I have no experience with antifreeze for the trailer.)

Bottom line: there shouldn't be this many workarounds and threads for something that should be bone simple.

Steve_O

I had the same problem and none of the fixes above helped. Turns out it was the check valve. The pump was not strong enough to generate enough suction to depress the check valve. See the video below for a solution. I had to prime the pump once I reversed the screen by holding the hose higher than the input and manually pouring in some antifreeze and the pump started siphoning right away. 

https://www.youtube.com/watch?v=woFYXINF4DM

Gomers2

Yes, it's the check valve. Reverse the screen so the cone points in and contacts the valve tip. The pump doesn't generate enough suction to open the valve like city water would, especially if it is sucking air to begin with. This is why it sometimes works when you get some liquid against the valve. NEVER press the valve button when the tanks are pressurized by the pump. Relieve pressure by opening taps first.