Document KRK2ZdpQp7b3qLk5z17p2pYmw

Heating Ventilating Air Conditioning Guide 1939 Chapter 13, Heating Boilers dampers, cleanouts and trimmings. The space at the rear of the boiler should be ample for the chimney connection and for cleanouts. With large boilers the rear clearance should be at least 3 ft in width. The boiler room height should be sufficient for the location of boiler u/h re a return header is used on a cast-iron sectional boiler to distribute 1 ' turns to both rear tappings, it is advisable to provide full size the r, tees instead of elbows where the branch connections enter the plugg tappingS. This facilitates cleaning sludge from the bottom of the accessories and for proper installation of piping. In general the ceilin height for small steam boilers should be at least 3 ft above the normal boiler water line. With vapor heating, especially, the height above the boiler water line is of vital importance. ^sections through the large plugged openings. An equivalent clean"t lug should be provided in the case of a single return connection. ^Mow-off or drain connections should be made near the boiler and so Janeed that the entire system may be drained of water by opening the When steel boilers are used, space should be provided for the removal and replacement of tubes. A^n cock. In the case of two or more boilers separate blow-off connec. must'be provided for each boiler on the boiler side of the stop valve CONNECTIONS AND FITTINGS Pii'the main return connection. ' Water service connections must be provided for both steam and water The velocity of flow through the outlets of low pressure steam heating boilers should not exceed 15 to 25 fps if fluctuation of the water line and undue entrainment of moisture are to be avoided. Steam or water outlet connections preferably should be the full size of the manufacturers' hollers for refilling and for the addition of make-up water to boilers. This ' connection is usually of galvanized steel pipe,- and is made to the return main near the boiler or boilers. For further data on pipe connections for steam and hot water heating tapping and should extend vertically to the maximum height available systems, see Chapters 16 and 17 and the A.S.M.E. Boiler Construction above the boiler. For gravity circulating steam heating systems, it isrecommended that a Hartford Loop, described in Chapter 16, be utilized in making the return connection. Particular attention should be given to fitting connections to secure con Code for Low Pressure Heating Boilers. Smoke Breeching and Chimney Connections. The breeching or smoke pipe from the boiler outlet to the chimney should be air-tight and as short and direct as possible, preference being given to long radius and 45-deg formity with the A.S.M.E. Boiler Construction Code for Low Pressure instead of 90-deg bends. The breeching entering a brick chimney should Heating Boilers. Attention is called in particular to pressure gage piping, water gage connections and safety valve capacity. not project beyond the flue lining and where practicable it should be grouted from the inside of the chimney. A thimble or sleeve grout Steam, gages should be fitted with a water seal and a shut-off consisting usually is provided where the breeching enters a brick chimney. of a cock with either a tee or lever handle which is parallel to the pipe Where a battery of boilers is connected into a breeching each boiler when the cock is open. Steam gage connections should be of copper or should be provided with a tight damper. The breeching for a battery brass when smaller than 1 in. /.P.5.9 if the gage is more than 5 ft from the of boilers should not be reduced in size as it goes to the more remote boiler connection, and also in any case where the connection is less than boilers. Good connections made to a good chimney will usually result in in. I.P.S. a rapid response by the boilers to demands for heat. Each steam or vapor boiler should have at least one water gage glass and two or more gage cocks located within the range of the visible length of the glass. The water gage fittings or gage cocks may be direct connected to the boiler, if so located, by the manufacturer, or may be mounted on a separate water column. No connections, except for combustion regu ERECTION. OPERATION. AND MAINTENANCE yThe directions of the boiler manufacturer always should be read before -"'the assembly or installation of any boiler is started, even though the lators, drains or steam gages, should be placed on the pipes connecting contractor may be familiar with the boiler. All joints requiring boiler the water column and the boiler. If the water column or gage glass is con nected to the boiler by pipe and fittings, a cross, tee or equivalent, in which a cleanout plug or a drain valve and piping may be attached, should be placed in the water connection at every right-angle turn to facilitate cleaning. The water line in steam boilers should be carried at the level specified by the boiler manufacturer. Safety valves should be capable of discharging all the steam that can be generated by the boiler without allowing the pressure to rise more than 5 lb above the maximum allowable working pressure of the boiler. This should be'borne in mind particularly in the case of boilers equipped with mechanical stokers or oil burners where the amount of grate area has little significance as to the steam generating capacity of the boiler. putty or cement which cannot be reached after assembly is complete must be finished as the assembly progresses. The following precautions should be taken in all installations to prevent damage to the boiler: 1- There should be provided proper and convenient drainage connections for useif the boiler is not in operation during freezing weather. f 2. Strains on the boiler due to movement of piping during expansion should be prevented by suitable anchoring of piping and by proper provision for pipe expansion and contraction. 3. Direct impingement of too intense local heat upon any part of the boiler surface, as with oil burners, should be avoided by protecting the surface with firebrick dr other refractory material. : Condensation must flow back to the boiler as rapidly and uniformly as possible. Ketum connections should prevent the water from backing out of the boiler. A-S.Af.E. Code. Identification of Piping Systems. ~. Automatic boiler feeders and low water cut-off devices which shut off the source 264