Troubleshooting a Leaky Steam Boiler

If you use a steam boiler to help heat your home, there may be times that it starts to leak. Sometimes, the problem is with the boiler itself and may be related to pipe or valves that are connected to it. This article will address common problems that cause leaks in steam boilers and some suggestions on how to correct them.

Check for Leaky Valves

One of the most common problems with leaking steam boilers is the temperature and pressure valve, or T&P valve as it is sometimes referred to it. Over time, the T&P valve can become damages from excessive pressure created by the boiler.

A way to check if the T&P valve is defective is to simply place a bucket under the overflow pipe. Then, flush the T&P valve to make sure that it is clear of any debris that may cause the valve to remain open and leak. If the leak remains, you will probably need to replace the temperature and pressure valve. However, as a temporary measure, you could try reducing the temperature on the thermostat setting to help prevent the boiler from overheating and opening the T&P release valve.

Checking for Pipe Leaks

Another common source of leaks with steam boilers is the water piping that leads to the boiler. Therefore, you should inspect the entire length of the pipe and check for any leaks or corroded joints that may be causing the leak. Also check for small amounts of metal shavings as this is an indication that the pipe may be punctured or corroded.

If you're able to find leaks, you'll need to plug them as quickly as possible. If the leak is that one of the coupler or T-connectors, you may be able to simply replace the fitting and use  Teflon tape to make sure the water doesn't leak out of the joined pipes. If the corrosion or puncture is in the middle of a water pipe, you can purchase a pipe coupler to repair the leaking area. This will require that you saw the pipe and remove a portion of it so that you can replace it with the coupler. You'll need a pipe threader to thread the ends of the pipe so the coupler can be properly fitted.

Inspect Tank for Corrosion

Although not very common with newer steam boilers, older boilers are susceptible to corrosion and rust in the base of the tank. So, if you have an older steam boiler, and you're experiencing leaks, you should inspect the bottom of the boiler tank to make sure that there is no rust or corrosion that maybe eating through the metal.

If the steam boiler itself is corroded or leaking at the base of the tank, it is generally a good idea to simply replace the steam boiler; rather than try to repair it. If immediately replacing the steam boiler is cost prohibitive or otherwise not possible, you may be able to use a silicon water sealant as a temporary stopgap measure. However, you should not rely on these types of sealants to keep the steam boiler from leaking for very long. If at all possible, replacing the boiler will save you a lot of work and money in the end.