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jnbellin
Dec 7, 2005, 08:14 AM
I live in Northern WI and have problems with my roof vent freezing and causing sewer gas to back up into my downstairs basement. My one 3" sewer vent looks the same as everyone else's but my vent freezes over every time the low hits 15 below zero. I did find an ArcticVent made by Heat-line, but I was wondering if there was something else I could do before going to this extreme.

speedball1
Dec 7, 2005, 08:27 AM
Greetings from a Beloit transplant to Sarasota,

There are various remedies for ice-plugged sewer vents. Some work better than others. One
Remedy for sewer vents which repeatedly freeze up is to insulate the vent pipe where it passes
Through the attic. A batt of fiberglass insulation wrapped around the vent pipe in the attic
May do the job.

Another remedy is to install one of the various styles of sewer vents that resist plugging
Because of the way they are designed. Improved vents are available from complete hardware
Stores and building centers.
Let me know if you have more questions. Tom

jnbellin
Dec 7, 2005, 09:23 AM
I will try the attic fix, but I don't think that will solve the entire issue, and may already be done as I have thought of that, but not done that yet.
On the special roof vent to prevent ice forming, I have seen something like that mentioned by other people, but I can't fine one online at Ace Hardware or Lowe's. Do you know where to find one online, I find that much better when going to the store, otherwise they just look at you and never figure out what you need.

speedball1
Dec 7, 2005, 11:16 AM
You should try insulating the attic pipes first but if that don't work and
Ice is the culprit you can go to the local hardware or plumbing supply house and buy commercial heat tape. It is actually a long cord like christmas tree lights but it has a heating element in it. It even has a thermostat in it to sense when it is freezing (BBBRRRRR) and warms the tape. It is designed to wrap around the pipes that are exposed in a crawl space to keep them from freezing, but it'll work magic for your vents as well. Leave it plugged in all winter, simply plug it into an outlet, or run an extension cord up close to the vents and staple the cord to the roof shingles, You asked for a online commercial anti-freeze vent. Click on, http://www.heatline.com/arcticprod.htm and check out their Arctic Vent. Good luck, Tom

cannonball
Feb 3, 2008, 07:25 AM
I live in Northern WI and have problems with my roof vent freezing and causing sewer gas to back up into my downstairs basement. My one 3" sewer vent looks the same as everyone else's but my vent freezes over everytime the low hits 15 below zero. I did find an ArcticVent made by Heat-line, but I was wondering if there was something else I could do before going to this extreme.
Here in Canada frozen vent stacks are very common. Lots of people climb onto their roofs and pour hot water into the stack. It's a little dangerous and a pain in the butt.

I found this info online that may be of some help. http//:Frozen Vent Stack and Water Lines (http://www.frozenlinesolutions.com)

My neighbor says he needs a permanent solution since he's getting too old to climb on his roof.

jnbellin
Feb 4, 2008, 07:11 AM
I did go in the attic and wrapped insulation around the vent tube and this year I also added blown cellulose insulation in the attic and blew all the cracks full around the roof vent. I can say we have had some very cold weather including multiple nights of 30 below with no issues.:)

cannonball
Feb 4, 2008, 09:20 AM
I agree that the simplest solution is to insulate the pipe where it passes through the unheated attic space. If this fails to solve the problem then heating cord or tape between the pipe and the insulation wrap will in most cases be the solution.

The only problem that's hard to solve will be if its occurring right where it exits the roof. But I'm sure that a insulation layer plus heating cord will transfer enough heat to reach that area as well.

jnbellin
Feb 4, 2008, 09:16 PM
I did try the heat tape before I did the insulation and that had no effect on the freezing vent pipe, the insulation keeps the gas warm enough that the warm sewer gas does not freeze in most instances in that last 2 feet of the exposed pipe.

cannonball
Feb 5, 2008, 05:51 AM
I did try the heat tape before I did the insulation and that had no effect on the freezing vent pipe, the insulation keeps the gas warm enough that the warm sewer gas does not freeze in most instances in that last 2 feet of the exposed pipe.

That's the problem with external heat tape and no insulation because in most cases with the heat loss when it's very cold there isn't enough heat to transfer into the pipe to melt the ice. That's why on any of my lines that are susceptible to freezing I have an internal heat cord to apply the heat directly to the formation of any ice rather then rely on the transfer through the piping.

I can say I have not had a freeze up in 13 years and it has been as cold as -47° during that time.

What you have done will probably work well but if it doesn't you could always try heat tracing it internally. It's far less costly then some of those high tech heated extensions available.

jimmyessbee
Dec 18, 2008, 10:13 AM
I've been dealing with this winter. I took a coffee can and made a hole in the end of it to fit my vent pipe. I put the can over the pipe. My vent pipe is such that the coffee can is almost the perfect length. I then stuffed my coffee can with fiberglass. It solved all my problems.

Milo Dolezal
Dec 18, 2008, 11:34 AM
I did go in the attic and wrapped insulation around the vent tube and this year I also added blown cellulose insulation in the attic and blew all the cracks full around the roof vent. I can say we have had some very cold weather including multiple nights of 30 below with no issues.:)

I am based in So. California. So, I am nor familiar with "vent freezing" .I am interested to learn more about this problem. What exactly happens ? Entire vent freezes closing the vent ? Can you expand on the subject in detail for me ? Can you post a photo ? Thank you...

speedball1
Dec 19, 2008, 05:47 AM
Perhaps a Arctic Vent is what you need, (see image) Check them out at; Water Line Heat Trace Freeze Protection For Cottage, Home, Commercial Water Pipe Applications - Arctic Vent (http://www.heatline.com/arcticprod.htm)
Good luck, Tom

jimmyessbee
Dec 20, 2008, 12:12 PM
What happens is that as the moist warm air rises through the sewer vent, it eventually goes through an area that is cold. If it is cold enough, the moisture condenses and freezes on the inside of the pipe. If it stays cold enough long enough and especially if the vent pipe isn't big enough, the vent pipe will close off due to the ice buildup. This is why they suggest 3" vent pipes when really even something as small as an inch would probably handle the venting. Of course, this problem often goes unnoticed. Often-times there is enough air in the drain pipes to take care of any gurgling that might occur because of blocked vent pipes. If, however, a septic system is getting old it can stink because of clogged drain fields. It's not a problem, indoors, if there is good venting. If the venting is blocked, however, some of that stink can work its way into the house. Also, methane gas is explosive and I guess can cause explosions.

nikospapa28
Jan 25, 2013, 04:03 AM
That fibreglas still allows the sewer gasses to pass through and escape? It does not restrict the gasses at all?

speedball1
Jan 26, 2013, 10:05 AM
Are you asking about the Artic Vent?

the sewer gasses to pass through and escape? You need to be informed about vents. The do not expel sewer gas. The pull in air to relive the suction in the drainage system caused by draining and flushing, REgards, Tom