Can you pour hot water down the toilet to unfreeze pipes?

Author: Prof. Helena Hills  |  Last update: Sunday, July 27, 2025

The answer is “yes” if the frozen pipe is a drain pipe. We cover several other thawing techniques you might want to consider using if you're dealing with frozen water lines. Below we'll discuss the proper method for pouring hot water down frozen pipes, as well as additional thawing tips to try.

How to flush a toilet if pipes are frozen?

You can apply heat to the exposed pipe to the toilet too with a hair dryer or heat gun, especially close to the wall so the heat will conduct back behind the wall. Sometimes it takes hours to thaw. Once you get it flowing, flush the toilet every two hours during severe cold to prevent a repeat.

What is the fastest way to unfreeze water pipes?

A frozen pipe can be thawed out using a hot water bottle, a heat gun, hair dryer or you can even use a blow torch set to low heat, providing your pipes are metal (do not use a blowtorch on plastic pipes). An outside tap cover is a great idea and can prevent pipes and taps from freezing- Outside tap cover | pr...

What can you pour down drain to unfreeze pipes?

Here are some tips that can help:
  • Boil water. Boil a generous amount of water and add a cup full of salt to it. ...
  • Baking soda. While the water is boiling, put around ½ a cup of baking powder in the drain. ...
  • Vinegar. Pour one cup of vinegar down the pipe immediately after putting baking soda. ...
  • Pour boiling water. ...
  • Run hot water.

Is it safe to pour boiling hot water down the drain?

No. Boiling water is not a proper drain clearing method nor is it for maintenance. This is especially important if you have PVC pipes, since those are wonky rated for 140F. The excessive heat can damage the pipes.

Will pouring hot water down the drain unfreeze pipes?

Is it bad to pour hot water down the toilet?

While it is okay to pour boiling water down sink drains, you should never use boiling water in your toilet, as the heat can cause the porcelain to crack. Instead, run your tub until the water is hot and fill a good-sized stockpot or bucket with it. Then, pour the hot water into the toilet bowl from about waist height.

Can you pour boiling water down frozen pipes?

All the above methods for thawing a frozen water pipe will work for thawing a frozen drainpipe, except for the torches-you DON'T want to use a torch on a PVC or ABS plastic pipe. Plus, here's a couple of other ways you could thaw a frozen drainpipe. Pour hot/boiling water down the drain and let it melt the ice.

What do plumbers use to unfreeze pipes?

Tip #7: A Thaw Machine Will Be Your Savior

It's exactly what it sounds like: a portable device that plumbers use to thaw pipes quickly.

How do you unfreeze a frozen sewer line?

Most frozen icy waste removal jobs can be completed using the cold water supply from a garden hose. Heated water is usually not required. Use a sewer jetter with a nozzle that has a forward jet to help penetrate the icy clog.

Will salt melt ice in the drain?

Really! Salt “melts” ice by lowering the freezing point of water to about 15 degrees.

Should I turn my faucet on if my pipes are frozen?

Keep the faucet open. As you treat the frozen pipe and the frozen area begins to melt, water will begin to flow through the frozen area. Running water through the pipe will help melt ice in the pipe.

How do I make sure frozen pipes don't burst?

Here is a list of eight things that you can do to avoid water pipe bursts:
  1. Keep Water Faucets Running. ...
  2. Direct Warm Air to Cold Areas of Your Home. ...
  3. Leave Your Cabinet Doors Open. ...
  4. Disconnect Your Hose from the Outside Faucet. ...
  5. Install Heat Tape. ...
  6. Seal Leaks That Allow Cold Air into Your Home. ...
  7. Check Your Home's Temperature.

How to thaw a frozen toilet supply line?

Turn a hair dryer on low and blow the heat from the dryer onto the frozen pipeline. Turn a hair dryer on low and blow the heat from the dryer onto the frozen pipeline. Go back and forth along the entire pipeline until the pipe heats to the touch and the water begins to fill the toilet tank.

How long does it take for toilet pipes to unfreeze?

It will take roughly 30-40 minutes of using a heat source to thaw exposed pipes. If the pipes are enclosed it will take longer for heat to penetrate the insulation between your heat source and the pipe.

Can frozen pipes cause toilet to clog?

Frozen Pipes and Water Blockages

Frozen pipes are usually not a local problem — they typically lead to system-wide pressure failure and other problems. If water cannot move freely through other fixtures, the toilet may not flush properly, making it more susceptible to clogging.

How do I keep my toilet water line from freezing?

How to Keep Toilet Pipes from Freezing Again
  1. Add insulation to the area around the toilet pipes. ...
  2. Add heating cables to the pipes on exterior walls, including your toilet pipes.
  3. If you'll be away from home for an extended period, turn off your home's main water supply valve.

How do you unfreeze pipes you can't reach?

If possible, locate the section of pipe that is frozen and thaw it yourself using gentle heat (slowly warm it up). If you heat the pipes up too quickly, they can crack or melt due to the quick change in temperature! Try wrapping an electronic heating pad around the pipe, heating the area with a hair dryer, or both.

How do I know if my main sewer line is frozen?

Read on to learn the signs of a frozen sewer pipe so that you can catch the problem before it gets worse.
  1. No Running Water. ...
  2. Visibly Frosty Pipe. ...
  3. Strange Sounds. ...
  4. Sewage Smells. ...
  5. Leaks.

What do you pour down drains to unfreeze pipes?

Easy ways to thaw a frozen drain pipe include turning up interior temperatures and wrapping pipes in hot towels. The job goes more quickly by pouring hot water or a mixture of vinegar, baking soda and salt water down the drain.

Will running hot water unfreeze pipes?

Pipe-thawing options: There are several things you can do to thaw your home's pipes. Here's a list: Probably the most popular and safest pipe-thawing option is to use hot water.

Can frozen pipes thaw without bursting?

And once the temperature outside dips below 32F, unprotected pipes are at a greater risk of freezing and potentially bursting. That said, it's still possible for your pipes to thaw without bursting. The key is to release the pressure and allow the pipes to thaw slowly.

How do you thaw frozen sewer pipes?

You can bring a small heater up on the roof and direct the heat into, it may help. You will have the best success if you remove the melting water with a shop vac. Both the salt and hot water options will work eventually but I think the hot water will work the best, aside from the mess.

Should I turn off water if pipes are frozen?

Thaw Frozen Pipes

Turn off the water immediately at the main shut off valve. Open the faucet so that water will flow through the pipe once the area is melted. This will help melt more ice.

Will boiling water damage pipes?

The pipes are held together with glue that becomes susceptible when the boiling water rushes over it. The damage is often not observed immediately but rather progressively deteriorates as time goes on. Additionally, your own health should be taken into consideration.

What is the best way to unfreeze plumbing?

How to unfreeze pipes
  1. Turn on the faucet. Keep it running. ...
  2. Apply heat to the frozen area. Slowly apply heat using a hair dryer. ...
  3. Continue to apply heat. Don't stop heating until the full water pressure is restored. ...
  4. Check all faucets and prevent pipes from freezing in the future.

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