1136A Motorized Reduced Port Valves

, for combustion air* 

up to 250°F, have a port diameter one size less than line size 
to facilitate proper valve sizing without the expense of reducing 
pipes at the valve. These valves feature self-cleaning discs. 1136A 
Valves are available with bracket and linkage for most standard 
control motors. Available in 3" to 14" sizes. 1136A valves are not 
available for manual operation.

1145 (Manual) and 1146 (Motorized) Hot Air Valves

, for com-

1145-H (Manual) and 1146-H (Motorized) High Temperature 
Air Valves:

 Identical to the 1145/1146 valves except for combus-

1155 (Manual) and 1156 (Motorized) Valves

, for combustion air* 

1145 or 1155 Manual Wafer Valve

* Not for use with fuel gases.

up to 250°F, are available in 3" to 30" pipe sizes. Available with 
all options that are off ered with the 1145/1146.

Sizing.

 Full port wafer valves in lines of the same pipe size give 

increasing fl ow for a fi xed pressure drop until they are about 
60° or 70° open. At greater openings, fl ow dœ s not increase 
appreciably, although pressure drop across the valve falls off  
rapidly--downstream piping or burners, not the valve, become 
the limiting resistance in the system. At 90° open, the valves 
fl ow resistance is negligible--its pressure drop is practically zero, 
and it can be ignored in pressure drop calculations. For control 
sensitivity, wafer valves should be selected for maximum fl ow at 
not more than 70° open.

Product Overview | Wafer Valves

Bulletin 1136A-1156

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