Maintaining Your Steam Boiler (Articles)
Bornstein Sons shares information about the Maintenance of Your Steam Heating System
As cold weather approaches, you gaze at your older NJ home and at the radiators that provide warmth to you and your family. It’s a classic New Jersey castle- cherry wood doors and moldings. Fireplace... oversized windows, elegant Victorian radiators and…… a steam heating system. The former owner has left you some notes on how to care for your system, but the paper is yellowed and aged, and the words can no longer be read at all.
If you are accustomed to other contemporary types of home heating be it forced air or hydronic baseboard, you need to be educated. A steam heating system is a living force in your home... it hungers, it speaks, and it even breathes! It is your responsibility as its keeper to provide for all its needs. This accomplished, it will give you the warmest, toastiest home you can imagine. Its embrace will keep you and your family warm on the coldest winter nights when your friends with other systems will be jealous of you!
Follow these simple steps…
Draining your steam boiler:
Cast iron steam boilers absorb heat from fuel and turn water into steam. The steam travels along steel pipes and through cast iron fittings to cast iron radiators. The radiators give off the steam’s heat, causing the steam to condense into water. The water returns back to the boiler through those same cast iron fittings and steel piping where it again absorbs the energy from the burn fuel, and the process is continually repeated. As steam and water flow through all those steel and cast iron surfaces, minute amounts of iron become oxidized… they rust. This rust is continually washed and drained back to the boiler. Water, once pure and clear will begin to take on the color of mild tea or in severe cases, black coffee. Clean water boils faster and easier than dirty water. We need to keep the water as clean as possible.
Boiler manufacturers advise that water be drained periodically from steam boilers. Your boiler has drain valves on it, at least two of them. The drain valves look a lot like hose faucets you might see in your laundry room or outside your house. They have a standard male hose thread. There is one on the lower part of the boiler, near the bottom. A second one is located on the lowest part of the return piping. The manufacturers advise removing water from each drain once a month. As a professional, I urge you to perform this task twice monthly. If you forget, well, you are back on schedule. If you forget monthly service, before long, the winter is over. Drain about 2 quarts of water from each drain, or till the water runs clear. You are doing two things. You are flushing “boiler mud” from the low points in the boiler and return piping. Boiler mud serves as an insulator, preventing the heat from burnt fuel from traveling to the water. You are also “thinning the soup”- reducing the amount of rust in the system as a whole. Don’t take out too much water. Excessive fresh water is also a problem to be discussed shortly.
Feeding your steam boiler:
Ok... you have drained the proper amount of water from your boiler and you are on the way to achieving maximum steam boiler efficiency. Your system also loses water through the various radiator vents and main vents during normal operation. Now, we have to put that water back! See that glass tube on the front or side of your boiler? That indicates the water level in your system. We like to see it between half and three-quarters full. Boilers are filled two ways. Most are fed manually via a valve on the water feed line. Crack the valve open, using the dial or lever handle. Feed slowly. The water level will rise in the glass tube. Shut the valve off tightly when proper level is achieved. Failure to fully shut off the valve can cause continuous feeding of the boiler, until the water level rises and rises... to the top of the boiler, through the steam piping, even up to the radiators. If you see water pouring out of radiator vents, it’s a good sign that your system is flooded.
Many boilers are equipped with automatic feeder systems. These will replace normal water loss with no effort on your part. This DOES NOT absolve you from draining your boiler as previously described! A potential problem inherent with automatic feeder systems is that they will always maintain your boiler’s water level, regardless of the nature of water loss. Earlier we wrote that excessive fresh water in a boiler is a bad thing. Fresh water contains dissolved air in it. You can see the bubbles come up when you fill your water glass at the kitchen faucet. The dissolved oxygen and carbon dioxide, when present in excessive amounts, can form mild acids in your system that can rot your cast iron and turn it into the consistency of wet cardboard. Keep an eye on your system. Periodically, during normal operation, check the radiator air vents for excessive steam loss. Check the radiator shut off valves at the base of the radiators. Visually inspect steam piping and vents in the basement. If there are consistent leaks of either water or steam, call a professional contractor and have them repaired!
Servicing your steam boiler:
You can perform most normal maintenance on your steam system. It is however; suggested that periodically, your boiler and system should be examined and maintained by a professional steam heating expert. He will properly check the function of your automatic feeder, pressure control, burner, thermostats, pigtail and low water cut off control. He can clean or replace an obstructed gauge glass. He will check for proper and safe combustion. Your chimney vent will be checked for proper draft and leaks, if needed, replace defective radiator air vents, too. Vents stuck in the open position will leak steam and waste water. Vents stuck in the closed position will prevent the radiator from ever getting warm. We have our cars serviced, why not our heating systems? We use them so often and are very dependent on them. Your steam heat professional has the tools and parts and expertise to provide that extra level of maintenance to minimize your needs for emergency service.