Document bMnj4M6OZnGQrEbvYDy27RBZ

Hoffman Specialty Co., Inc.________ Specialties, Heating VENTING VALVES FOR ONE-PIPE VACUUM SYSTEMS , RT___ Fu>aT wuyc pinq>--, In construction, the No. 2 Valve is similar to the No 1 --Am check wit> the addition of a vacuum diaphragm in the base an5* an air check over vent port. Upon steam contact, float diaphragm (7) expands closing port (2). When pressure goes below atmosphere vacuum diaphragm (8) follows up contracting float diaphragm, maintaining port closed against air intake. Air check (1) functions only in the case of a half-hot radiator when float diaphragm (7) is not expanded by steam contact. With a cessation of steam generation, air check holds port closed against air intake until pres sure goes below atmosphere and when a 1 in. vacuum forms diaphragm (8) expands, closing port, relieving air check.of any further function. The superiority of the diaphragm controlled port compared with valves having air check only is indicated by the fact that the total pressure exerted in holding No.! Hoffman Siphon Air and Vacuum Valve vent port closed is approximately 20 times greater than that exerted in maintaining an air check closed. This greater pressure, exerted by the vacuum dia- phragm holds the valve pin more tightly against its seat and also aids in crushing or pushing away dirt particles which might be caught between the valve pin and its seat. Radiator Connection J-fi in. Maximum guaranteed operating pressure 10 lb. Fur nished with special short siphons for narrow pattern radiators. The No. 6 Float Air and Vacuum Valve is similar in design and application to the No. 5 with the additional feature of the Air Check or Vacuum starter above vent port and vacuum diaphragm in base. Used for venting ends of mains, vento stacks, etc., where water is liable to be present. Pipe connection, % in.; vent port for less than 3 lb. is itfe in.; for 3 lb. and over is Yg in. Unless otherwise ordered, will be shipped with Y\ G in. port. Maximum guaranteed operating pressure, 10 lb. The No. 16 Air and Vacuum Valve is used for venting ends of steam and dry return mains. Valve is 3% in. high overall, permitting installation in lines close to ceiling. If has the special Hoffman feature, the combined air check and vacuum diaphragm for preventing return of air to system. Pipe connection, % in. Vent port Yl6 in. dia. , No. S Maximum operating pressure, 10 lb. No. 10 The No. 3 Hoffman Air Line Valve is specially designed for Air Line, or as they are frequently termed "Paul" Systems. It is sensitive in action and closes the instant steam fills the radiator. Radiator connection, H in.; Air Line connection, Ys in. Maximum guaranteed operating pressure, 10 lb. THE HOFFMAN VALVE LOCK Prevents theft of No. 1 and No. 2 valves in public buildings, etc. No extra tapping is required as lock is easily applied when valve is inserted, in radiator. By using set screws, valve is locked in position and can only be removed by a special key. Hoffman Valve Lock Write for Descriptive Circular--Locking the Door Against the Heat Thief 800 a Hoffman Specialty Co., Inc. Specialties, Heating HOFFMAN "CONTROLLED HEAT" EQUIPMENT The No. 7 Hoffman Adjustable Modulating Valve-- For use in Vapor or Vapor Vacuum systems, is made in % in. size, angle pattern only, having a range of adjust ment up to 200 sq. ft. of direct cast-iron radiation. After installation, whether the system is in operation- or cold, the port of each valve is adjusted for the size of the radiator to which' it is attached. Adjustment is simple; loosen a locknut; turn valve handle until proper number of graduations are visible on the dial plate; then tighten locknut. The valve handle may then be moved to admit sufficient steam to heat a quarter, half, three-quarter, or entire radiator. The valve stem stuffing box has a frictionless metallic fibre.packing No. 7--Hoffman Ad- that will last indefinitely and require no iuetable Modulating attention, giving at the same time, a valve Valve action so free that the pressure of only one finger is required to open the valve. TOP DIAL PLATE ADJUSTMENT Pori Area for 00 eq. ft. . Radiator Pori 'Area for 60 tq. ft. Radiator Dial tel for 00 eg. ft. Dial eel for 60 eg. ft. The visible adjustment aids the designing engineer by enabling heating contractor to make a final accurate adjustment which compensates for slight irregularities in pipe sizes, failure to ream pipe, installation of extra fittings not foreseen in original layout, etc. The advantages of an adjustable port in forced hot water systems to secure proper balance makes the No-. 7 Valve especially adaptable for such use. The No. 7 Valve is regularly supplied with lever handle. On special orders, it can be furnished with wood wheel, lock shield, closed top, extension stem and handle, or chain pull. The Nos. 8 and 9 Hoffman Return Line Valves--These valves are automatic, non-adjustable, thermostatic and relieve all air and condensation without the loss of steam from radiators, pipe coils, indirect radiation, steam mains and risers, steam kettles, sterilizers and other devices where it is desired to get full efficiency and economy without waste of steam. In service, they have established a reputation for efficiency and consistency of operation with the same degree of sensitiveness under either high or low pressure. The body of the valve is made of cast steam metal; cap Sectional View and tail piece are hot brass forgings; the thermostat of a Noe. 8 and 0 Return Line Valves special Hoffman alloy. In continued operation the ther-. mostats will not break, stretch or lose their tension, giving long life and perfect operation. CHIEF FEATURES The valve consistently operates under a pressure range from 13 in. of vacuum to 50 lb. steam pressure. Water at a temperature of approximately -12 deg. less than, the temperature corresponding to the steam pressure- causes full valve opening and free discharge of condensation. Write for Descriptive Circular--Hoffman "Controlled Heat" 801 it