The Golden State: Where & How to Live, Secure, Visit, Enjoy and Thrive in California
Care And Repair Of The House
Heating And Ventilating
1. HOW TO FILL A HOT-WATER OR STEAM-HEATING SYSTEM
The method used in filling a hot-water heating system is the reverse of that used in draining the system (explained in Ch. XI, sec. 3). The filling is more easily done if two persons work together—one controlling the flow of water into the boiler and the other operating the radiator relief valves.
Open all radiator shut-off valves and be sure that the air valve on each radiator is closed. See that the draw-off cock at the lowest point in the system is closed, and then open the valve in the supply pipe which feeds the boiler. As soon as the water begins to rise in the pipes, open the air valve on each radiator, beginning at the one nearest the boiler, to release the air so that the, radiators may fill with water. When water begins to spurt from the air valve, shut it off and proceed to the next radiator. Repeat this operation until all radiators are free from air and full of water.
When adding water to a boiler with fire under it, be sure that the fire is low, and let the water in gradually. A large volume of cold water suddenly injected into a hot boiler may cause it to crack.
Gravity System.
In the case of the gravity system, the supply-pipe valve should be shut off when the water has risen to such a height that the expansion tank at the top of the system is one-third full. (The expansion tank is usually located on an upstairs closet shelf or in the attic, preferably near the chimney, to protect it from freezing.) The height of water in the tank is usually indicated on a water gage glass attached to it. Always keep the water at the level mentioned, to insure complete circulation throughout the system.
Pressure System.
In the case of a pressure system, see that the radiators are all well filled with water. Whether or not they are full may be determined by opening the air valves. The flow of water from the supply pipe is usually controlled by a separate automatic valve, which shuts off the supply when the water rises to the proper height. Expansion of an oversupply of water is taken care of by an automatic release valve attached to the outlet pipe, which opens and allows excess water to flow out of the system. When the water falls below the required height, the automatic valve opens, allowing enough water to enter to fill the system. The regular shut-off valve in the supply pipe is left open where an automatic valve is used.
