Document G56GpXa3wRron0db6gv5oRMrv
Hoffman Specialty Co.
Specialties
No. 4 Hoffman Quick
Vent Valve
For quick venting mains, blast coils or for any service where water is not a factor. Vent port %" dia. Pipe connection either H" or
List Price, $2.80
No. 5 Hoffman Quick
Vent Float Air Valve
Permits quick vent in return line vapor systems or for service where water is encountered and must not be permitted to pass through the vent port. Pipe connections 34"- Specify A" port for pressures of 3 lbs. or over; A" port for less than 3 lbs.
List Price $8.00
No. 6 Hoffman Quick Vent Float Air and Vacuum Valve
Is adapted for venting
return lines and for other
service where return of
air to the system is not
desirable. Pipe connec
tions
Specify A"
port for pressures of 3
lbs. or over; A" port for
less than 3 lbs.
List Price, $ 12.00
The No. 4 Hoffman Valve is suitable for venting steam or vapor lines, when water is not encountered, nor vacuum required..
The No. 5 Hoffman :Valve is suitable for venting steaih'or vapor lines where water might be encountered. The No. 5 valve will freely vent. air and close against steam or water.' ~
The No. 6 Hoffman Valve operates the same as No- 5 valve except that it closes after venting air, preventing re turn of air to the system.
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Fig. 1 shows correct applica tion of Nos. 4, 5 or 6 Hoffman Valve for venting end of steam or vapor main.
l<=~^0=c Fig. I
Fig.- 2 shows correct applica tion of Nos. 4, 5 or 6 'Hoffman Valve for venting indirect radiator.
Fig. 3 shows correct applica tion of Nos. 5 or 6 Hoffman Valve for venting False Water line loop, providing by-pass for draining or cleaning.
Fig. 4 shows correct applica tion of Nos. 4, 5 or 6 Hoffman Valve for venting steam coil in stor age tank.
Hoffman Specialty Co.
Specialties
l dValve Body (7)CaGE
^Spacing
fit) Special Spring Bronze Diaphragms
[iJIlii
(4)Valve Pin (io) Valve Port yi-
SCCTtONAl view
(B)Valve Body Cap (9)FlaT Phosphor Bronze Spring '6)Thermostatic Chambers OHJnion Nut
(12) Cage Port
HOFFMAN RETURN LINE VALVES No. 8 and No. 9
Special Operative Features
The Hoffman Return Line Valve positively distinguishes between steam;- air and water, freely passing the air and water but stopping the steam. It is nonadjustable. The thermostatic parts are interchangeable and may be shifted' from onq valve body to another of the same size without affecting the proper operation of the valve. Under atmospheric conditions the thermostat is set to maintain a wide open valve at 200 degrees Fahr., but, when steam, under atmospheric conditions (i. e., no pressure) but with a temperature of 212 degrees reaches the valve the thermostat fully and completely expands, tightly closing the exhaust port of the
valve.
One of the chief features of the Hoffman Return Line Valve is its consistency of operation within a pressure range of from 13" vacuum to 50 pounds pressure. Within this range, condensation at a temperature of 10 to 12 less than the tem perature corresponding to the steam pressure will cause a full valve opening
In determining the valve capacity for blast coils~the condensing power of such coils should be calculated on the basis of being four to eight times greater than radiator cast iron surface, the minimum outside temperature determining which
factor to use.
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