How to Fix a Toilet that will not Flush Due to Frozen Pipes?

What to do when your pipes are frozen and you cannot flush your toilet.

Waking up or coming home to a toilet that will not flush is a horrible thing to have to deal with. It is much worse when you realize that it is due to frozen water lines. Now you may not know how to thaw your water lines, where your water lines are, or if you will have any broken lines once the ice melts. This article is here to help you get through this trying time and get you back to flushing your toilet with confidence.

What are the first steps to fixing your toilet?

The first thing you will need to know is where the main shut-off to your house is located. Depending on the residential area, it may be in your yard under a manhole cover or in a basement or utility room. You will need to know where this is because frozen water expands, which means the icy water within your pipes could have expanded and cracked your water lines. Once the water thaws out, it will begin to leak water into your home, and you will need to be able to shut it off quickly.

You should now flush your toilet if you have yet to do so. This will allow the water to fill the toilet once it has thawed and alert you of the returning water pressure. Next, try and find out which water line feeds your toilet. If your home is on a slab, then the frozen line will be in a wall or at the edge of the concrete. Neither of which will allow you to access them. 

If the water line goes down into a basement or crawlspace, then you can attempt to locate them. There are several ways to tell which water line is frozen. Lightly tap on it with a screwdriver handle is one. The pipe will sound solid if it is frozen or hollow if it is not. Sometimes the pipe will have frost around the outside of the pipe, which is also a dead giveaway. Or you can feel the lines. All of them will feel cold, but the frozen ones should be noticeably colder.

How do you thaw the frozen pipe?

Now that you have found the frozen pipe, how do you get it thawed out? You have several options for this as well. 

  • Blow dryer: Using a blow dryer on its lowest setting is an excellent way to defrost the pipe. Start at the place closest to the toilet and work the hairdryer up and down the line in sweeping motions until your toilet begins to run.
  • Heat tape: There is a product commonly referred to as heat tape. It will wrap around your pipe and plug into an outlet or extension cord. Heat tape will gently warm the line as far as you have installed the heat tape and begin to melt the ice.
  • Heating pad: If you have a heating pad that you would use for sore muscles, then this is another excellent option. It will work with a similar concept to heat tape by gently warming up the pipe.
  • Space heater: Depending on where your pipe is frozen, you may be able to place a space heater near it. If it is above or directly underneath the floor, turning up your home’s heater may also help to warm the pipe.
  • Hot towels: An option is to use hot water to warm towels and place them onto the pipe. You will want to replace them as they cool off.

A word of caution

Using any flame to try and thaw the pipes can be extremely dangerous. For example, using a hand torch may melt the line, burn the sheetrock, or catch your home on fire. Although it may take longer for it to thaw through the other methods, it is much safer than attempting to use an open flame to heat your plumbing pipes.

What can you do to prevent frozen water lines?

If your residence has a basement or crawlspace underneath it, one option is to seal this area before the colder months affect you. Closing all the exterior vents, shutting, sealing any exterior doors, and sealing any windows will help tremendously.

Specific pipes can be wrapped with electrical heat tape, which will keep them above freezing. With heat tape, you will need to remember to plug and unplug the heat tape as the weather threatens your water lines. You may need to use some form of tape to keep the electrical heat tape in place. If you are using a secondary tape product, you will need to ensure that your tape is rated for a temperature above what the heat tape will produce. Commonly heat tape requires a tape product with at least a 176-degree Fahrenheit heat rating.

Pipe insulation may help tremendously. This is sold by big box stores and local hardware stores alike. Traditionally it looks like a black pool noodle with a slice from one end to the other that allows you to slide it around the pipe. This insulation will be sold in specific diameter sizing, so you will need to know which size of water line you need to insulate.

Time to flush

If you have begun to heat your pipes, it will be time before you have water again. Once the water does start to flow back into your toilet, you will want to do a thorough examination to ensure that you do not have any broken water lines. This could happen anywhere from under your sink to under your house. Having water spraying from a broken pipe is not only costing money, but it can damage the structure of your home and will need to be dealt with immediately. Hence, turning the main water valve that we referenced at the beginning of this article. 

If you cannot solve the frozen pipe issue yourself or have any trouble, you should call a professional. Broken water lines can cause a significant amount of damage. Call a professional if you don’t know what to do next or feel overwhelmed. They will know precisely how to handle your situation.

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