20+ Year "Rookie's" Anti-Freeze Mistake

[Cburg]

I been doing this for more than 20 years with a bunch of different campers and RV's and up until last year I never had a problem doing this. You would think after doing something that many times one would know just how to do it and not mess it up.


Last year, we hosted at a campground right up until the snow plows started running so to say I was rushed to winterize the RV was an understatement. So I was not sure just what I did but It took almost 8 gals. of anti-freeze to get the job done. I didn't know why it keep coming out the HWT (hot water tank) drain but did so I caught what a could and saved maybe 4 of the 8 gals. Like I said time was against me I just had to get-er- done!


This year. We ended early. So I had lots of time. So I got my normal 2 gals and started the chore. I put the HWT in by-pass but the anti-freeze just came out again like last time. Now I thinking, " How does a By-Pass Valve Go Bad?"


So before I start pulling out the tools... I pull out the book(s). Thinking maybe I burned out a brain cell and not a the valve. I check the books. I look here on the forum, I look on You-tube, No my cells are fine, must be the valve ... I guess I got a project for the morning....


I am sure by now the most of you know what is going on here. But the answer was nowhere to be found and that is the reason I am writing this out, My Daddy always said if you got a problem and if you have the time, Sleep on it, It may solve itself.


It was about 4-AM when I woke you and had my answer. The by-Pass Valve was fine. It was indeed stopping the water (ant-freeze) from going into the HWT's inlet side of the tank. it was sending the anti-freeze to all the hot water lines BUT also through line connected to the OUT-let side of the HWT and therefore letting the ant-freeze come in the "backdoor" of the tank.


The fix was simple. The same thing I did for years in the past (everyone should do) .... DRAIN THE HOT WATER TANK LAST, BUT not where does anyone say that. The do it. But they never say " Do Not Drain the Tank Until the Last Step!? and here is...


why.... With the HWT full of water, There is no room for anti-freeze to enter the tank so it just go through the hot water lines.


So my Rant is over... I hope you all had a good laugh. My hope is that a "New B" or 20 year rookie will see/read this and save she/him self some grief .


Stay Safe !



Cburg

[Ray,IN]

Humm, I've always drained the water heater while the fresn tank was draining, then winterized. My heater bypass/ valve is 12V, as is my winterizing system.
Your one-way valve at heater outlet is faulty. For some reason W installs check valves on both cold inlet and hot outlet.

[7997redtail]

No I agree with the OP. I did the same thing(empty the HWT first) and waisted a lot of antifreeze. Since, then I’ve left the HWT till last.

However, the last few years I’ve used air to blow the system out, HWT emptied last, then poured antifreeze into the traps, disconnected the water pump and run it dry then left all the water taps opened all the.

[7997redtail]

One thing I should point out. The current RV has a single bypass valve. Previously RVs had two bypass valves. When you have two you don’t need to leave the HWT until last IMO.

[Bobn1957]

Originally Posted by 7997redtail

One thing I should point out. The current RV has a single bypass valve. Previously RVs had two bypass valves. When you have two you don’t need to leave the HWT until last IMO.

I had a leaking check valve and installed a second bypass valve when I replaced the check valve!

[Mtn Charlie]

Move to Florida. Problem solved!

[RVWinnie25B]

The HWT has 2 valves that need to function to prevent the antifreeze from entering. The 1st is your bypass valve to prevent cold water, the 2nd is a check-valve on the hot water side of the HWT that is meant to only allow hot water out. So, I would say the check-valve is bad if it is allowing cold water or antifreeze to enter.

[GeorgiaBill]

Thanks for the rant. I spilled a lot of anti freeze last year because I failed to remove a hot water filter on my 2018 Trend. I've been trying to remember what mistake I made and you jogged my senior brain.


Thanks a lot.
-Bill

[Morich]

Originally Posted by RVWinnie25B

The HWT has 2 valves that need to function to prevent the antifreeze from entering. The 1st is your bypass valve to prevent cold water, the 2nd is a check-valve on the hot water side of the HWT that is meant to only allow hot water out. So, I would say the check-valve is bad if it is allowing cold water or antifreeze to enter.

It will always depend on the specific RV we have but this is what the OP is missing when antifreeze feeds back into the water heater! On his RV there should be a check/one way valve on both the input to let cold water into the heater but also a check valve on the output to avoid water coming back.

If the OP has been successful in the past and now the antifreeze feeds back into the water heater, the logical explanation is that the check valve on other heater output has failed and is not closing!

On this RV , the drawings do show two check valves, one on in and one on out.

I believe what RVWinnie25B was trying to point out is that the problem is not a "brain freeze" ! Those are easy to understand and can be easy to fix.

But in this case, I think the real problem is a stuck check valve that lets water or antifreeze come back into the heater through the output check valve!
Harder to fix or maybe just ignore?
The idea of a stuck check valve is not a crisis, just a bit of nuisance to remember to do things different and then ignore a bit of waste on reheating water that has already passed through the heater once!

Depends on personal outlook, how much time/effort to fix it?