Frozen drain line

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
Status
Not open for further replies.

1750

Minister of Fire
Apr 21, 2013
532
Michigan
Can I take advantage of the collective brilliance of this place to help me figure out how to thaw a frozen drain line?

I discovered sewage backing up out of the floor drain in the mechanical room and a downstairs shower. According to the plumber I asked to look at it, the pipe is frozen closed in both directions from the outdoor clean-out. He didn't have any suggestions for me that didn't involve thousand dollar bills.

So, it's a mechanical problem... I need to remove the ice from the 4 inch pvc drain line -- or wait until spring.

I have access to cold water from the outside spigots. Maybe I can use that to melt the ice in the trap? I wondered if I could run a hose out of my on-demand hot water heater?

Thanks in advance for any thoughts on this.
 
Try putting some salt in that outdoor cleanout or possibly RV anti freeze. If theres anything getting past the frozen part at all you can get it cleared with hot water as well.
 
I was wondering about making a hot salt solution. I wonder if that hurts the biology in the septic tank?

Of course, there's not going to be anything in that tank if I don't get the ice out of that line.

Thanks for that suggestion!
 
Salt wont work if its a 100% ice blockage. If the water is slowly draining through you may have luck with salt/water solution but it will take a long time and a chit ton of salt. A power sewer auger might work the best.
 
Be careful with those do it yourself power augers. One way to find out if anything is getting by is with on of those garden hose balloons drain openers. the are relatively cheap,$15-18 for a 4" pipe Attach it to the hose slip it into the cleanout and turn on the water. The rubber balloon expands to seal the pipe and the jet of water going forward will look for any way thru unless its froze solid.
 
Salt wont work if its a 100% ice blockage. If the water is slowly draining through you may have luck with salt/water solution but it will take a long time and a chit ton of salt. A power sewer auger might work the best.
The plumber who was here was a Rotorooter guy. He had one of those and didn't seem to think it would help. Though, the guy was kind of a wiener so maybe he just didn't feel like messing with it.

Be careful with those do it yourself power augers. One way to find out if anything is getting by is with on of those garden hose balloons drain openers. the are relatively cheap,$15-18 for a 4" pipe Attach it to the hose slip it into the cleanout and turn on the water. The rubber balloon expands to seal the pipe and the jet of water going forward will look for any way thru unless its froze solid.
I haven't seen one of those balloon things, but I'll look for one. The clean out looks frozen solid, but maybe it's must mostly frozen solid.

I was thinking maybe I could get a hose adapter for an interior faucet and melt it into the clean out that way? Or, has anyone ever heard of something like a hose tape that you could plug in and work into the pipe as the heat did its trick?
 
I had luck once with the old style dipstick heater. Depending on how far your trap is from the opening as I doubt it would bend around that but if you have a few feet without a bend or a cleanout in the yard it should work. They usually heat to about 100-120 degrees. Make sure it is submerged in water though.
 
I thawed out a water line riser that was froze solid under a house 2 weeks ago with a heat gun and section of 2" flex metal conduit duct taped to the gun. Dryer vent might also work in a pinch.
Might be a long process but hay/straw bales over the line for a few days might help especially if the outside temps are up like they are calling for.
 
Last edited:
I think your idea of running a hose from your water heater is as good as any.
I'd block the drain inside with a test plug, balloon plug or anti-backflow plug so you don't flood yourself any more. Start by trying to thaw the line from the clean out to the tank first, then switch sides & thaw towards the house. If a garden hose is too big/not flexible enough then make an adapter for the end to some small plastic tubing.
Keep any extra lengths of hose/tube inside if possible to keep more of the heat in. gonna be a slow process.
Good luck. Sounds like a crappy problem ==c(sorry)

BTW whatever you do make sure you are not making steam inside a blocked pipe (BOOM!)
 
I was thinking maybe I could get a hose adapter for an interior faucet and melt it into the clean out that way? Or, has anyone ever heard of something like a hose tape that you could plug in and work into the pipe as the heat did its trick?

I would think an electric freeze tape for water pipes would work here. they have short ones it would probably keep the water in your cleanout warm so it could work its way in each direction. remember to leave the thermostat part outside so it remains on. They are sealed up pretty good so i dont think there is a hazard. Come as small as 3Ft.
 
I got the line from the cleanout to the tank open! But now I realize the cleanout is angled and I can't get the headed up toward the house. Any suggestions? I thought the cleanout would just be a straight up T but it's not.
 
I know methanol will melt the ice! Good for the septic, I doubt it!
 
How far is the floor drain to the cleanout? I assume the cleanout is outside and you have an area from the cleanout to the house still frozen? How far? You could use the hot water hose from the drain toward the cleanout if it is not too far. There should be a cleanout just inside the foundation where the sewer goes out. Some pros use 1/4" polyethylene with hot water to jet lines. If you can hook up hot water is better, but the cold water spigot will thaw a line slower. More of a mess in your basement. Lots of vacuuming water. Good Luck!

I have had my garage drain freeze a few times. It just drains to the yard. I have a hot water spigot in my garage. I run a garden hose out the window and up the outlet. Last week I thawed it out - almost 15 ft up. About as far as I could push the hose. It will thaw fast about an inch in 4 seconds.

As a sidenote, there are hundreds of houses in SE Minnesota with frozen water service lines this cold winter. Still haven't heard much about frozen sewers. I am surprised by that as lots of sewer lines are much shallower than the water lines.
 
First post on here. if its shallow enough to freeze then dig it up and wrap the pipe with heat tape. Im a plumber, frozen dwv mains are usually repaired by replacing the frozen section, accompanied by measures to prevent future occurrences
 
Well, we did it! A serious relief.

This angle in the cleanout is why I couldn't get the hose in going upstream.

The whole thing is only 7 or 8 inches deep. I'm surprised it didn't happen sooner. I'll have to figure out some way to insulate it.

Thanks again to all of you for your help and good or advice!
 

Attachments

  • image.jpg
    image.jpg
    186.4 KB · Views: 885
Laying sheets of styrofoam over the lines, then covering with the dirt may help.
 
How far is the floor drain to the cleanout? I assume the cleanout is outside and you have an area from the cleanout to the house still frozen? How far? You could use the hot water hose from the drain toward the cleanout if it is not too far. There should be a cleanout just inside the foundation where the sewer goes out. Some pros use 1/4" polyethylene with hot water to jet lines. If you can hook up hot water is better, but the cold water spigot will thaw a line slower. More of a mess in your basement. Lots of vacuuming water. Good Luck!

I have had my garage drain freeze a few times. It just drains to the yard. I have a hot water spigot in my garage. I run a garden hose out the window and up the outlet. Last week I thawed it out - almost 15 ft up. About as far as I could push the hose. It will thaw fast about an inch in 4 seconds.

As a sidenote, there are hundreds of houses in SE Minnesota with frozen water service lines this cold winter. Still haven't heard much about frozen sewers. I am surprised by that as lots of sewer lines are much shallower than the water lines.
Yes, the hot water did the trick! If I could have gotten the hose headed upstream toward the house, I would have been done in no time, but just couldn't make the bend. There isn't a trap close to the foundation on the inside and I didn't have a vacuum, so I'm really glad I could thaw the pipe from the outside through the pvc. Putting more water into the system was what I was trying to avoid (it was coming up out of the floor drain in the furnace room).

First post on here. if its shallow enough to freeze then dig it up and wrap the pipe with heat tape. Im a plumber, frozen dwv mains are usually repaired by replacing the frozen section, accompanied by measures to prevent future occurrences
Welcome to Hearth.com, wsm0807! This is a great place and I hope you like it here. I appreciate you responding to my request for help. I'm surprised this was so shallow; I'd have assumed code would have required it below the frost line. Do you have any suggestions for preventing future problems?
Laying sheets of styrofoam over the lines, then covering with the dirt may help.
I was thinking something like that. Or, even building a box around it with foam on three sides.

Thanks again.
 
Status
Not open for further replies.