How much RV anti-freeze for traps, etc...? : LUSENET : TimeBomb 2000 (Y2000) Preparation Forum : One Thread

I've seen a few threads on avoiding freezing pipes and drains, and one of the recommendations was, after draining the pipes, to put anti-freeze down the drains. What I thought was a better suggestion was to put RV anti-freeze down the drains because that is supposed to be non-poisonous.

Anyway, does anyone know how much needs to be put down each drain? Each toilet? (to keep the traps from freezing...)

Does anyone know whether this stuff is harmful to septic or mound systems?

On a slightly different yet related topic: while I do have a general sense of how to drain the water from the water heater, I am not quite sure what happens after that. This is an LP water heater-- if we didn't drain it at all, would the pilot light keep it warm enough to prevent freezing? If we do drain it, what do we do about the pilot light? (There are three settings: Off, pilot and on. I was told by one plumber to turn the setting to pilot when draining. But when I tried to find info from the mfg. of the water heater they said that the pilot would need to be turned off if the water heater wasn't going to be refilled right away.) I know I should know more about this stuff, but I don't. Trying to learn as fast as I can, but that may not be fast enough. Thanks in advance to any of you who can help fill in the gaps.

-- winter wondering (, September 14, 1999


Hi, WW,

The maximum freeze protection will be obtained when the mixture of water and antifreeze in the traps is half and half. More antifreeze than that actually RAISES the freezing temperature.

Don't know if there are any disadvantages to using Propylene Glycol (food grade) as compared to Ethylene Glycol (regular antifreeze used in your car), but I know that many people use the latter in their traps in vacation homes.

I doubt if the bacteria in your septic system (what is a "mound" system?) would care which one you used. I imagine they aren't fond of either one, but the amount you would be using would be so small in proportion to your septic tank that it shouldn't be a problem.

When you drain your water pipes, it's necessary to open all the faucets so vacuum "pressure" doesn't keep the pipes from draining. Make sure you open a valve or faucet lower than the pipes which may be running under the floor, or they'll freeze. If you can't do that for some reason you might want to blow them out with a compressor, if you have access to one. Problem is that if there is water standing in a pipe it may or may not break when it freezes. Depends on how the freezing action takes place. Better to play it safe.

I don't recommend trying to keep the water heater from freezing by utilizing the pilot light. It probably would prevent freezing, depending on the temperature reached in its space, the size of the heater, the BTU's of the pilot, etc., but what if the pilot light blows out while you're gone? Or the gas shuts off for some reason.

I also don't recommend leaving the pilot light on when the tank is empty. You might want to talk to your gas company on this, but I would thing the pilot might get the wall of the tank hot enough to damage the glass lining in the tank.

I've read enough of your postings that I SHOULD remember where you live, but don't (another senior moment). Are you in a climate where the pipes and water heater are likely to freeze inside your house? Where I live, that would be almost impossible, because when the sun is out, the houses stay way above freezing inside, and when the sun is not out, it's generally warm and rainy.

Hope this helps.


-- Al K. Lloyd (, September 14, 1999.

Hi Al,

Thanks for answering and also inquiring about our temps/likelihood of freezing pipes here... Unfortunately we are in a colder climate. In our current house we've never had a problem. Of course we've had no major power outages, either. The old house (no insulation, no central heat) we did have a few problems every so often. A family member who lives up the road had a housetrailer and she had problems every winter with needing to thaw pipes. The worst temps I've seen here were in the -30 and -40 range. With windchills to -95. 'Course the pipes aren't supposed to care about windchills, but...

And, those were the low temps at their extreme. Last December I remember having wonderfully warm weather at the beginning of the month. Didn't need a jacket in the daytime.

As to 'what is a mound system'-- it's a modified septic system that can be put in in an area if the perk test to check soil drainage fails. A mound of earth/gravel/sand etc. is built as the drainfield. In a cruel twist of fate, when looking into alt. sanitation measures, I discovered that what I thought was to be a completely gravity fed sytem _wasn't_. It's gravity from the toilets and drains to the first septic tank, and then to the second tank that holds the effluent from the first. But (sigh) from the second tank to the mound requires a pump. We had the system pumped last month and asked the guy about how it worked, and what the capacity was. I wrote it down, but don't have it on hand. I think from the last time the pump runs, there is a capacity of 400 to 500 gallons. And I don't actually know how often the pump runs, so if the pump hasn't run and 300 gallons have accumulated... Someone else had suggested retro-fitting to a traditional septic-- but I think we are stuck. It's all regulations. And if we could have put a traditional septic in, we certainly would have. Mound systems start at $10,000.00. And if you're unfortunate to get the unscrupulous plumber my sister did it'll cost you more like 20k... Of course, I have to admit, since the perk failed and we were required to put in the mound, I really have no idea about how expensive regular septic sytems are...

If I've piqued anyone's interest about mounds and you just _have_ to read more about it, some links: (sorry I don't know how to hot link)

-- winter wondering (, September 14, 1999.

Hi, WW.

I wondered if that was what a mound system was. We have the same thing, it sounds like, here in Oregon, but call it a "sand filter". I have one on a rental house I built about ten years ago.

My memory of Ohio is that it is rather flat, but that is probably like calling Texas (where I grew up) dry.

My point is this: if there is enough drop between the septic tank and the "mound", you can power the system by gravity rather than with a pump. That is the way I did mine, as I HATE the idea of relying on power to make the septic system work.

This gravity system operates on a siphon principle. Whenever the septic tank fills (actually it's a secondary compartment in the tank, but may be analagous to your second tank) with about 90 gallons of effluent, it causes the siphon to drain that 90 gallons through the "mound" under pressure. In order to pass "code" there has to be at least 12 ft of drop to the "mound", but it would also work with somewhat less drop. Ask a septic system installer if you think you might be able to modify the system. Also, ask him what happens if the pump fails. Does the system fail, and cause the inability to use your plumbing fixtures in the house? Or does it just cause it to function more slowly?

Good Luck, let me know what you find out, ok?


-- Al K. Lloyd (, September 14, 1999.

WW, by coincidence, I'm helping a friend lay out his property for a new business, just down the road. He is having a contractor install a sand filter, and I'm hanging around a lot, asking lots of questions, trying to learn as much about them as possible. I've personally designed and built several systems, but this is the first sand filter.


-- Al K. Lloyd (, September 15, 1999.

Thanks Al! (both for the info and the concern). I'm sorry I didn't get back to this sooner-- it's not always easy to track down a septic installer to ask questions. Luckily the person I did manage to talk to was very nice and I learned a few more things about the mound. (I was thinking of sending this to you via e-mail, but wasn't sure if yours was real.)

The gravity / siphon type modification you suggested will, as you noted, only work if the mound is more or less down hill from the second tank. (Actually, didn't mean to mislead, I'm not in OH, the OH web link about mounds just happened to be one that I found on my web search for them. And so it is fairly hilly here.) In the case of our mound, it unfortunately isn't downhill from the second tank. It actually happens to be slightly uphill from it. :-( Maybe that's okay, because I have a feeling the cost to retro-fit it would be prohibitive.

Then I moved on to pump failures, etc. Evidently, if the pump fails or for whatever reason the liquid level in the second tank gets to a certain point, the tank alarm (in the basement) will go off. I asked if that alarm requires electricity. Yes, but it is on another circuit-- or supposed to be on another circuit. I didn't choose to bring up y2k scenarios at the time. No elecricity, no alarm. If the alarm goes and it's because of a pump problem/failure, then the pump needs to be replaced. Range of $250 to $400 quoted for pump and 2 hrs labor.

The conversation then went on to how many years until a mound system fails, etc., how to know it's failed, what happens if it fails, etc., until I got back to asking him your pump question, which was: "what happens if the pump fails. Does the system fail, and cause the inability to use your plumbing fixtures in the house? Or does it just cause it to function more slowly? " Answer: "Once the alarm goes off (mm-hmm) the tank has a capacity of about 300 gallons that it can hold. After that, it will back up into your basement."

Oh joy...

We also happened to discuss how ?ironic? (for lack of a better word) it is that half the time when a septic is pumped out to a truck, that they turn around and spread it out on fields (not for human consumption fields, certain restrictions...). I was pretty sure it was untreated, and he verified that it was. Untreated, that is...

Now back to the RV anti-freeze part, I did pick some of this up, and on the bottles for this kind it said in big letters "DO NOT DILUTE". Might that be a difference between the two types of antifreeze?

I'm going to be going through computer withdrawal tomorrow and the whole weekend, so I won't be able to check back until sometime (hopefully early) next week... I feel a little trembly already... ;-)

-- winter wondering (, September 16, 1999.

Hi, Winter Wondering,

Sorry it took ME so long to get back. I was interrupted by visitors, and haven't been able to get back to you due to reevaluating my water situation. I earlier dug down beside my well, and attached a pipe fitting at a level (nine feet underground) well below my static level. I tested it at a minimum of four gallons per minute all summer. But just recently (and I think it's because we've had a VERY dry summer), the static level has dropped to below my pipe fitting. So all the research I've been doing on solar pumps, based on using a surface pump, were in question (if I have to use a submersible, it's a lot more money, and more hassle to put it down the well.)

So I've been busy changing the well AGAIN! Now I've got a siphon going, and I believe that that will suffice unless the well drops a lot more. It's running over two gallons per minute, which is 3000 gallons per day. As long as the static level stays above 29 ft or so, (currently at eleven feet), I'll be ok.

So back to work on designing a pumping system.

But to YOUR questions:

OK, so your system can't be converted to gravity; too bad, but all is not lost. My friend's system is also uphill from his house; in fact, he has to have TWO pumps--one to pump from the septic tank to the mound, and another to pump THROUGH the mound. He has no power to either pump, and doesn't expect to until next summer at best. So he is going to monitor the level in the septic tank, and also in the pump reservoir at the mound (both are easy to do). When either place approaches getting full, he'll borrow my generator, and pump them. He has disconnected all his water except his toilet (I'm not sure about his kitchen sink, which I don't recommend disconnecting ) from the main line to the septic. This grey water runs out on his lawn. His toilet only produces 1 1/2 gallon per flush. Thus, he figures he'll only have to borrow my generator every few months (one flush per day only fills the 300 gallons of reserve space in his septic tank every 200 days. Reduce the time if there are more people in your family proportionately, and reduce further if your kitchen sink drains into the septic) You know the saying, don't you,"yellow, let it mellow, brown, flush it down" Well, he live on a large lot, as most of us around here do, and doesn't use the toilet for the "yellow" part. In fact, one of my neighbors has a sign on her front door which reads, "Men, go pee in the bushes. I'm tired of cleaning up your splatters!"

Anyway, if you can get under your house and customize your drains to facilitate dumping your greywater somewhere besides the septic tank, not only will you be able to reduce the frequency your pump has to run, but will actually make your entire system last longer, as the worst thing for your system is to let lots of water run into it. The houses I've built for myself (three in the last 25 years) all have separate grey water systems. If you do it right, it's good for whatever plants reside in the area where you drain it. Just avoid flat ground, as it tends to get boggy and smelly. Best to drain it on a hillside. I have experience in this....

Of course you can leave your system alone, and pump it every two or three days, or less, but without power, that requires a substantial amount of generator run time. I was not aware that the septic pumpers dumped raw sewage onto fields, although I suspected as much. Around here (at least), that is highly illegal, as it should be IMHO.

As far as RV antifreeze saying "do not dilute" on the bottle, I can't say. Could be, as you speculate, the difference in the types of antifreeze, but I'll bet it's because it's already diluted.

WW, do you have a generator? If not, how long are you expecting to be without power? If you are primarily worried about brief outages, it may not be a problem, as the pumps typically don't run all that often. Of course, if the pump is JUST ABOUT to need pumping when the power goes out, then there's a problem.

Also, if you don't have any power, will you have any water to drain into the septic tank? Do you have an electricity free water source?

One last thought on your septic. If TSHTF, you can always deal with your shit without the septic system. There are lots of ways. The least controversial way I've heard mentioned is the "sawdust toilet". haven't used one myself, but it sounds pretty good. I HAVE used an outhouse for many years, long ago. I am not all that fond of them, in some ways, but they are a good back up system, and easier, and certainly more reliable, than a generator.



BTW, I jumped to the conclusion that you were in Ohio from the source for mound systems. Duh. Where DO you live, if you don't mind my asking?

-- Al K. Lloyd (, September 21, 1999.

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