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Vapor Power International LLC
551 S County Line Road, Franklin Park, Il 60115
Phone: 630-694-5500 Fax: 630-694-2230
NOTE: PER CODE, BOILERS WITH GREATER THAN 100 GALLONS NORMAL WATER
CONTENT MUST HAVE 2 BLOWDOWN VALVES IN SERIES. A QUICK
OPENING VALVE IS RECOMMENDED FOR THE REDUNANT BLOWDOWN
VALVE AND SHOULD BE MOUNTED UPSTREAM OF THE SLOW-OPENING
VALVE..
Blowdown piping must be at least the same size as the blowdown valves and
must be directed to an unrestricted discharge drain, separator or tank,
depending on the local code requirements. Pitch the pipe toward the drain so
that the boiler will drain completely by gravity.
NOTE: IF THE POINT OF BLOWDOWN DISCHARGE IS ABOVE THE BOILER
BLOWDOWN CONNECTION, THEN AN ADDITIONAL VALVE SHOULD BE
ADDED TO FACILITATE DRAINING THE BOILER BY GRAVITY (IE, WITHOUT
BOILER PRESSURE).
2.3.1 SURFACE BLOWDOWN
If the boiler is supplied with an automatic surface blow down valve, pipe to a
point common with the bottom blowdown piping.
2.3.2 WATER COLUMN BLOWDOWN
If the boiler is not supplied with a water column blowdown valve, install such
a valve on the bottom cross of the water column and pipe to a point common
with the bottom blowdown piping.
2.4
SAFETY VALVE(S)
The ASME approved safety valves(s), supplied with the boiler, should be
factory set at or below the design pressure of the boiler as stated on the boiler
nameplate.
NOTE: THE SYSTEM OPERATING PRESSURE MAY BE LIMITED BY THE SYSTEM
COMPONENTS OTHER THAN THE BOILER, IT IS THEREFORE ADVISABLE
TO CHECK THE SAFE WORKING PRESSURE OF ALL COMPONENTS IN THE
SYSTEM AND IF NECESSARY, REPLACE THE SAFETY VALVE WITH A VALVE
SET AT A LOWER PRESSURE, BUT WITH SUFFICIENT CAPACITY (3.5 x KW =
LBS/HR REQ’D) TO ASSURE COMPLETE SYSTEM PROTECTION.
