7
6 - 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 2 - Safety Relief Valve
