Draining A Boiler In Your Boston Home

In my last post, I talked about winterizing a property that will be vacant/unheated over the winter. In this post, I’ll talk about how to drain and winterize a boiler-based heat system in your Boston home.

If you have a boiler, you’ll need to turn off the heating source and drain the water from the system if you expect the home to be vacant during the winter months. Turn off the main circuit breaker that powers your boiler controls and if needed, extinguish any gas or fuel feeding the burner by closing off the appropriate valves, or extinguishing the pilot light. You’ll need to let the water in the system cool for two to three hours before you drain it. Turn off the main water supply for the boiler.

At the base of the boiler, you’ll find a drain port that looks like a garden faucet. Attach a garden hose to the drain and direct the water to a floor drain, utility tub or sump well. Because a hot water or steam heat system is pressurized, you’ll need to open the bleeder valve on the radiator located at the highest point in the house. Make sure all of the other radiators in the system are able to drain. Depending upon the size of the tank, the draining process may also take a while to complete.

At Boston Standard Plumbing & Heating, we add anti-freeze to boiler systems to prevent residual water from freezing and to inhibit corrosion of the empty system. We can also assist with refilling a formerly inactive system and bleeding the air out of the radiators and pipes.

As a side note, boiler water doesn’t smell very good. This is not unusual and doesn’t indicate a problem, but it is the sign of a biologically active process. (Yes, some water-borne bacteria can survive boiling.) The smell may be stronger if the boiler water has been stagnant for awhile, such as might be the case during the summer. If the smell of the water is bothersome, open a window or use a fan to provide fresh air during the draining process.

Regular boiler maintenance is important. You should be draining a boiler about once each year. Doing so will give you the opportunity to spot corrosion problems, and will also allow you to refresh the rust inhibitor in the system. Proper boiler maintenance can extend the life of your tank, too.

When you need to drain the boiler for winterization, you don’t need to do anything special, however you may want to provide a little extra attention to the system when you refill and restart it. Rust inhibitor is a must, and bleeding the air out of the system will help reduce noise and uneven heating throughout the home.
At Boston Standard Plumbing & Heating, we’re trained to maintain, winterize and restart boiler heat systems. If you want help or a consultation, please call (617) 288-2911. We’re available around the clock to help you with all of your heating needs.