Winterizing a Hymer Aktiv (or a Roadtrek)

[AktivCanuck]

I have a Hymer Aktiv but I mentioned the Roadtrek in the title because they were made in the same factory and share much of the same tech, so owners of both may be comfortable responding to my questions.



So this class B RV has a fresh water tank, a water heater (it's a Truma Combi, which provides the heat for the van and heats the water) and two sinks (one by the stove and a flip-up sink over the toilet). The "tank" for the toilet is actually a removable container, or "cassette" as they call it.


I drained the fresh water tank, emptied the grey water tank and the black water cassette. I drained the hot water tank and ran both sinks until no water was coming out. I figured doing this would reduce the time the dealer spends winterizing it and reduce my bill. Ha!!! It is a flat rate $210 + $10 for RV antifreeze + taxes. So I paid nearly $260 for them to complete a winterizing. That's motivating enough for me to want to learn what I have to do to winterize it myself going forward!


I know I don't have to do anything to winterize the cassette. My understanding is I don't need to do anything with the fresh water or grey water tanks. What else needs to be done? I'm thinking:


- Flush the cold water lines with RV antifreeze (hose into jug)
- Flush the hot water lines with RVA
- Truma combi unit???
- Other???


I found a Truma video that talks about needing a bypass kit for the the Truma Combi if you use "winterizing fluid" in the RV, which doesn't come with the Combi. Now I am concerned, as I don't know if the RV has this bypass kit and I know the dealer put in RV antifreeze.


How does one flush the hot water lines with RVA? Since the hot water comes from the Combi, which has been drained, I gather there must be a hose that I can put into the jug, just like for the cold water, and let the pump push the RVA through?


Is there anything else that I need to do to winterize the lines?


Thanks!

[Winterbagoal]

Originally Posted by AktivCanuck

I have a Hymer Aktiv but I mentioned the Roadtrek in the title because they were made in the same factory and share much of the same tech, so owners of both may be comfortable responding to my questions.



So this class B RV has a fresh water tank, a water heater (it's a Truma Combi, which provides the heat for the van and heats the water) and two sinks (one by the stove and a flip-up sink over the toilet). The "tank" for the toilet is actually a removable container, or "cassette" as they call it.


I drained the fresh water tank, emptied the grey water tank and the black water cassette. I drained the hot water tank and ran both sinks until no water was coming out. I figured doing this would reduce the time the dealer spends winterizing it and reduce my bill. Ha!!! It is a flat rate $210 + $10 for RV antifreeze + taxes. So I paid nearly $260 for them to complete a winterizing. That's motivating enough for me to want to learn what I have to do to winterize it myself going forward!


I know I don't have to do anything to winterize the cassette. My understanding is I don't need to do anything with the fresh water or grey water tanks. What else needs to be done? I'm thinking:


- Flush the cold water lines with RV antifreeze (hose into jug)
- Flush the hot water lines with RVA
- Truma combi unit???
- Other???


I found a Truma video that talks about needing a bypass kit for the the Truma Combi if you use "winterizing fluid" in the RV, which doesn't come with the Combi. Now I am concerned, as I don't know if the RV has this bypass kit and I know the dealer put in RV antifreeze.


How does one flush the hot water lines with RVA? Since the hot water comes from the Combi, which has been drained, I gather there must be a hose that I can put into the jug, just like for the cold water, and let the pump push the RVA through?


Is there anything else that I need to do to winterize the lines?


Thanks!

Except for drain the water filter, if you have one under the sink, you could have pretty much stopped there (After "Ha!!"), and before getting the dealer involved.
I usually use a valve fitting (screws into the FW entry point and has a nbicycle valve sticking out) at the fresh water connection for shore water, and a small compressor to blow out the lines for a while, after draining everything you've done. Leave all the faucets/taps/entry/exit points open (unless there's a good reason to close them) and let things air our naturally, and it leaves room for expansion along the lines, in case there are some pooled water in them. I'll sometimes run the water pump for a while until there's no more gurgling, or spitting at the faucets.
I have never used RV A/F in over 14 years of winterizing. The stuff is not worth the effort, except if cold weather camping, a little in the black gray tanks doesn't hurt.

[AktivCanuck]

Thanks for the reply winterbagoal.


That's quite the "location" entry you have there!!! So I gather you are in Sarnia, which may not get quite as cold as here but certainly gets well below freezing.


I am really surprised to read that you have never used RV fluid, but perhaps your compressor "blowout" negates the need for that; similar to getting an irrigation system blown out in the fall.


I have neither the configuration nor the compressor for this. I gather I just need to put the hose into the jug, open the taps and run the pump until coloured fluid comes out and then pour some down the sinks? I'm not clear how that would work for the Truma Combi unit itself though. How would I get RV fluid into it?


As a side note for anybody reading this, I did communicate with Truma after seeing a video that said RV fluid should not go into the combi. Truma said that is only a concern if the owner plans to camp after winterizing and use the Combi for heat, as the RV fluid will crystalize from the heat and damage the unit.

[Winterbagoal]

Originally Posted by AktivCanuck

Thanks for the reply winterbagoal.


That's quite the "location" entry you have there!!! So I gather you are in Sarnia, which may not get quite as cold as here but certainly gets well below freezing.

Can't lie, tired of being told what to do by "experts" less than half my age. Politicians, too. No more masks, no more silly rules, open the damn US border, is my mantra now. You have deciphered the cryptic location clue. Well done, Grasshopper.

Originally Posted by AktivCanuck

I am really surprised to read that you have never used RV fluid, but perhaps your compressor "blowout" negates the need for that; similar to getting an irrigation system blown out in the fall.

Same principle as winterizing your swimming pool plumbing, get as much water out of the pipes as possible, and leave the lines open for the expansion/freezing of anything you miss. Have done it this way on 3 different RV sizes for over a decade without any problems.

Originally Posted by AktivCanuck

I have neither the configuration nor the compressor for this. I gather I just need to put the hose into the jug, open the taps and run the pump until coloured fluid comes out and then pour some down the sinks? I'm not clear how that would work for the Truma Combi unit itself though. How would I get RV fluid into it?

I forgot to add the RVAF down the sinks and traps part, but you have it covered. As one who has never used the water pump/hose in jug/fill lines with RVAF method, I will assume you are correct. Sounds right. I have the Truma Aqua Go Comfort Plus water heater, with a separate gas fired furnace. I have to drain the Truma AGCP, and open the low point drains under the motorhome to let the return lines drain. Fairly simple, done twice, no problems.

Originally Posted by AktivCanuck

As a side note for anybody reading this, I did communicate with Truma after seeing a video that said RV fluid should not go into the combi. Truma said that is only a concern if the owner plans to camp after winterizing and use the Combi for heat, as the RV fluid will crystalize from the heat and damage the unit.

Makes sense. I think you could skip the dealer next year.

[magicbus]

My Truma Combi came with the required bypass already installed. You can tell if you have one if you find a valve near the Truma with both a blue (cold water) and a red (hot water) connected to it. This bypass diverts the cold water into the hot water lines.

One other thought, if you have a shower valve separate from the sink make certain you leave it open. I learned the hard way they are delicate and shouldn’t have fluid if any kind left in there. BTW, we typically get to the low teens in the winter so I drain, run the pink stuff, drain that, and push in the check valve on the fresh water fill by sticking my finger in the fill and pushing the valve.

[KanzKran]

Originally Posted by AktivCanuck

I found a Truma video that talks about needing a bypass kit for the the Truma Combi if you use "winterizing fluid" in the RV, which doesn't come with the Combi. Now I am concerned, as I don't know if the RV has this bypass kit and I know the dealer put in RV antifreeze.

How does one flush the hot water lines with RVA? Since the hot water comes from the Combi, which has been drained, I gather there must be a hose that I can put into the jug, just like for the cold water, and let the pump push the RVA through?

I had to add bypass valves to mine for the same reason. I suspect it's because the Combi water heating section gets hot when using the cabin heat function, whether you want it to or not. It was a pain because I had to do all the work reaching through drawer openings, and one PEX crimp was done blind. And I messed it up and it leaked, so I had to cut the band off with a Dremel tool with abrasive side cutter wheel and do it again. Correctly.

To winterize, I open the two low point drains, the fresh tank drain, and the Truma drain until they all run dry (with all faucets open, including outside shower), then stick the end of my short 'winterizing' hose into a jug of -50 RV antifreeze (propylene glycol; no alcohol), connected to the city water connection, turn the Kantleak valve to "sanitize/winterize", close the faucets, start the pump, and one by one work the faucets until only pink runs freely. Toilet pedal, too. It takes a little more than a gallon, and I run the rest through the sink drains and shower floor drain.

Letting the pump push it through insures the strainer bowl has no clear water in it, along with the pump which can split if not drained or had antifreeze run through it. If you don't have a winterizing setting on the city water connection, you can add one to the suction side of the pump instead.

I usually then drain the low point drains back into jugs to use for flushing the toilet on the road in winter, at least until it's warm enough to de-winterize. There's not a lot of reason to leave that stuff in the lines (its job it to push the clear water out, same as using compressed air), though some say it's harder to get out if allowed to dry. We don't drink tank water, so I don't care, but you might.

The long white line in the photo is the bypass line. The red and blue were original.

[Winterbagoal]

This video suggests that the Combi is winterized once it's drained completely. At the 02:30 second mark it discusses drainig it completely, and then says you're protected from damage once it's drained. Sounds like the RVAF is optional.

https://www.youtube.com/watch?v=omPpnm04mM8

I just drain my Truma AquaGo Comfort Plus water heater, and that's all I do. No problems in 3 cold winters in my driveway.