Frozen Pipe

karen2

My pipe froze on my heater. It is the pipe that is the 'out take' pipe.

Water comes out of it. How did this happen and can I insulate it?

I am thinking if I insulate it..it will raise it off the floor, then the water would flow backwards



We use propane.

Also in the gas heater forum (water in heater) there is a picture of a heater. This is what ours looks like..on the bottom left of the picture there is a white pipe coming from the heater, that is where the water comes out from and that pipe is what is freezing.



Thank you for any help. Dover Projects recommended you.

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Tim McElwain

I could not find the posting you

mentioned in the water heater section. It sounds like the pipe you are referring to is a condensate line coming from a condensing water heater or boiler. A picture would help or get me a direct link to the picture you mentioned.

karen2

Frozen pipe pic

Here is a picture of a heater (not ours). If you look to the bottom left near the floor, you will see a small ( 1/2 to 3/4 inch) pipe coming out of the heater. It plastic, almost pvc like material.

Jean-David Beyer

Picture is too small ...

for me to tell, but I think Tim is right that it is  a condensate drain. You cerainly do not want it to freeze up. If it did, the condensate would back up into the furnace. The only way to raise that line would be to raise the entire furnace, which might be possible, but expensive.



I am a homeowner and have a condensing boiler. As the condensate comes out of the boiler, it immediately encounters a T on its side. The top is open, and the bottom goes straight down to a condensate pump. If that froze up, the condensate would spill out onto the floor (in my garage) from the top of the T. So far, I have not had a freeze up. The lowest temperature outside has been 7.5F since I got this boiler. The garage is a little warmer than the outside, but is not deliberately heated. The only heat in there is from the exhaust pipe and from the hot water pipes. That is not much. When the boiler is firing, I can feel warmth from the exhaust pipe, but it is not much; I would guess under 110F, but I have not measured it. The water in the hot water pipes can go up to 135F, but usually does not. They are insulated with 1/2 inch foam insulation.



On your furnace, your T is  in "wrong". I do not think this will hurt anything much, other than it might dribble onto the floor when operating normally. It might be that it is tipped down to the left, and then it would not dribble. But if that line is frozen, I would expect water to dribble out from that T. In any case, that line should be continuously slope down until the condensate comes out of it; it should not be a trap. There should be a trap inside the furnace so that combustion products not come out into your boiler room, but that one should not freeze since it is inside the shell of the furnace.



I guess it would not hurt to insulate that pipe, but I would not expect too much. Just how cold do you suppose it is in the room with that furnace? Do the other water pipes in there freeze?

karen2

Frozen Pipe

Thanks for the replies!



No other pipes have frozen except that one.

All other pipes are insulated.



The pipe in question has frozen when the weather was really, really cold. I believe we were -6 for a couple of nights. The high during the day was like 10.



The pipe rest on the floor. The floor is cement and it's cold. The temp in the cellar probably runs in the 40's or so. We do not heat the cellar.



We have been here for 7 winters and this has never happened. I went and checked the pipe last night before bed and it was fine. I am going to take a picture of the pipe today and will post it.



You posters are so wonderful to help me out. I appreciate it!!

Tim McElwain

You could have a

heat tape hooked up to come on when temperature drops below a certain number. A picture of your installation would make it easier to advise you as how to install the heat tape.

karen2

Frozen Pipe Pics

Here are 2 pictures of the pipe. One shows the pipe coming from the furnace. The shows the pipe at the end.

Jean-David Beyer

Pictures very different.

The pictures you just provided are very different from the one you showed before.



See where it comes out of your furnace, hits a 90 degree elbow that points it to the floor, hits a second elbow that sends it off somewhere, probably outdoors, where it empties out. I do not know what is inside your furnace, but there should be a trap in there to prevent combustion gasses from escaping that way. I suggest you replace that first elbow with a T lying on its side (so the top of the T is vertical). The top part leave open, and the bottom part points to the floor. The rising part of the T goes into the furnace where the elbow was.



There are two reasons to do this. First, the open part of the T allows air in so when the condensate is produced slowly, it will not be trapped but flow out quickly. You do not want water sitting in that pipe, especially where it is outdoors, since it can freeze that way.



Second, if that pipe freezes, condensate can spill from the open part of the T and make a mess instead of stopping your furnace. You might want something to catch the water.



Another thing you could do is have your pipe switch to 1 1/2 inch pipe before it goes outside. You might do this in the straight pipe between where the two elbows are now. And if you shorten the straight piece between where the two elbows are now, you could have that drain pipe steeper so the water would run out faster, giving it less time to freeze.



Remember, I am not a professional, so it will be interesting to see what they have to say about this.

RobbieDo

Freezing

Some furnaces have the traps built into them, some don't. I would be hesitant on putting heat tape on the condensate drain as it's PVC. Insulation on the pipe won't help in this case. A condensing furnace should NEVER be put in a place where the temps are subject to freezing. Pitch the pipe more and this might help? Good luck

karen2

freezing pipe

Thank you so much for the reply. Can you tell me what you mean by 'pitch' the pipe?



Thank you!

Tim McElwain

Pitch - elevate the pipe so it is

draining away from the unit. This will  prevent water laying in the pipe and freezing. It may also be a good idea to replace the existing pipe with a larger one therefor less chance of freezing.May be 1" or 1 1/4" PVC.

Jean-David Beyer

Pitch

Pitch is similar to slope. It is the amount a pipe rises or falls over a given distance. A gentle slope would go up or down a foot over a distance of 100 feet. A very steep slope would go up or down one foot over a distance of one foot. For drain pipes, a drop of 1/4 inch per foot is typical. Increasing the pitch might involve having it drop 1/2 inch over a run of one foot. I am not a professional, but I would suggest for a condensate line, you would want that drain to be no less than 1/4 inch per foot, and possibly it would be better to have it drop 1/2 inch per foot. That may not be possible because of the geometry of your situation. If that drain must go 50 feet, for example, it would have to drop a little over a foot, and you may not have that much distance available. Sometimes a condensate pump can raise the level.



My boiler is in my unheated garage. It is slightly warmer inside than outside, but not much (here in New Jersey). I have a condensate pump that raises the water about 6 feet from the ground, and the tube drops 4 feet over a distance of 6 feet. That is very steep. Just before it goes outside, it changes from about 1/2 inch i.d. tubing to 1 1/2 inch PVC pipe. That pipe has never frozen. I suppose my condensate pump could freeze, and if it did, condensate would spill all over the floor.



Let us wait until the professionals chime in about the most suitable slope for that drain pipe, and what size it should be.

Jean-David Beyer

Boilers and freezing temperatures.

I would expect in the installation manual of a boiler that it would specify the environment where it should operate. Mine is very specific about the air intake being kept away from harmful chemicals. They also seem to think it is OK to install it in a garage, since they specify that if it is in a garage, it should be at least 18 inches from the floor, and they specify the ventilation space around it. But they do not specify the temperature.



The explain how swell it is, that if the boiler gets below 40F, it turns on some of the circulators and fires it low until it gets up to 45 F, and so on. But they do not have anything to say about the possible freezing of the condensate.

RobbieDo

Freezing

Well, I'm here to tell ya that it will freeze, it's water. Mfg never state that a condensing boiler or furnace can be put in a area that is subject to freezing temps.

martin

freezing condesant drain

The T idea is a good idea , also give the pipr a little fall it must be going to a floor  drain or sump pit seeing it is in a basement. then slip a piece of foam insulation around it to keep it from losing its heat till its empty. Then try to figure out why your basement is so cold. All that cold air in your basement is just causing a chimney effect, driving your heat and your bills thru the roof.