How to Thaw a Frozen Septic Pipe

A length of red piping with icicles hanging off of it.
  • 1-4 hours
  • Beginner
  • 25-500
What You'll Need
Hot water
Heat lamp or electric heater
Heat gun
Electric heat tape
Pipe thawing machine
What You'll Need
Hot water
Heat lamp or electric heater
Heat gun
Electric heat tape
Pipe thawing machine

Frozen septic pipes can have disastrous results if left alone. The waste can be forced out, overflowing in your yard, or the expansion of the fluid can also cause the pipes to break. There are many different ways to prevent this from happening, such as wrapping and insulating exposed pipes, but they can still freeze depending on where you live and the local weather conditions. Use these guidelines at your own risk to try to solve your frozen septic pipe problem.

Warning: There are many times where it is best to hire a professional plumber to unfreeze your pipes or to work the equipment. If anything goes wrong with them, the pipes will definitely burst and this will be very expensive and messy to repair and clean up.

Step 1 - Use Hot Water

One of the most common solutions for frozen pipes is to pour hot water into them. This sometimes thaws the pipe if the frost is not too critical, but you should use this method with caution, for if the pipes are completely blocked with ice, pouring hot water in the pipes can make them burst. Also, make sure that your water isn't too hot for the pipes! Some materials, such as PVC, have a heat threshold that your water temperature shouldn't cross; otherwise, you could damage the pipes accidentally.

Step 2 - Heat the Pipes

This method will only work if you can access the section of pipe that's frozen. Get an electric heater or a heat lamp, plug it in, and aim it at the septic pipe. The electric heater can warm up the air and cause the ice to melt. The procedure might take a long time, but it is effective.

Step 3 - Try a Heat Gun

If the ice still has not melted after being heated for a few hours, you can proceed to using a heat gun. Move the heat gun back and forth to distribute the hot air around the septic pipe. You can also use a hair dryer in the event that you do not have a heat gun.

Step 4 - Use the Electric Heat Tape

There are many times where the freezing is severe, so you might need a more drastic solution. You can wrap the electric heat tape all around the frozen area that you wish to thaw. One end of the electric heat tape should be plugged in to a 110 volt outlet. The process is very slow but it has the advantage of gradually thawing the pipes and keeping them from freezing further.

Step 5 - Rent a Pipe Thawing Machine

If you do not have a pipe thawing machine, you can go to your local hardware store and rent one. Put the frozen section of the septic pipes in the middle of the spring-loaded clamps that are part of the machine. Once you have turned on the machine, the septic pipes will start thawing.

Ideally, one of these methods should fix your problem or else it is time for professional help. Once your situation is fixed, consult help about what steps you can take to prevent this from happening again next time the temperature drops.