Dunkirk WPSB Series II - Manual (Page 7)

7
CONNECTING SUPPLY AND RETURN PIPING
RELIEF VALVE
DISCHARGE
LINE
Check local
codes for
maximum
distance
from fl oor
or allowable
safe point of
discharge .
WARNING
Burn or Scald Hazard. Discharge line shall be installed to relief valve outlet connection to avoid burns,
scalding, or water damage due to discharge of steam and/or hot water during operation.
Discharge line shall:
• Connect to relief valve outlet and piped down to safe point of disposal. Check local codes for maximum
distance from fl oor or allowable safe point of discharge.
• Be of pipe size equal to or greater than that of the relief valve outlet over the entire length of discharge
line.
• Have no intervening shutoff valve between safety relief valve and discharge to atmosphere (do not plug
or place any obstruction in discharge line.
• Terminate freely to atmosphere where any discharge will be clearly visible and at no risk of freezing.
• Allow complete drainage of the valve and the discharge line.
• Be independently supported and securely anchored to avoid applied stress on the relief valve.
• Be as short and straight as possible.
• Terminate with plain end (not threaded).
• Be constructed of material suitable for exposure to temperatures of 375°F (191°C); or greater.
Refer to local codes and appropriate ASME Boiler and Pressure Vessel Code for additional installation
requirements.
!
Figure 1 - Safety Relief Valve