Jordan Valve Mark 78 Series – Globe Style Control Valve - Manual (Page 5)

If You Experience Overriding:
 Usually caused by scale or foreign matter holding the
plug open - inspect and clean or replace.
 May be caused by failure of the diaphragm – replace
diaphragm as needed.
 May be caused by too high a spring setting – adjust
if necessary.
 May be caused by insufficient instrument output pres-
sure.
If You Experience Leakage or Erratic Regulation:
 Excessive pressure drop - reduce with pressure regu-
lating valve.
 Plug may be binding.
 There may be excessive foreign matter in seat.
Ordering Spare Parts
Use only genuine Jordan Valve replacement parts! Re-
placement parts for this Jordan Valve product are kept in
stock for immediate shipment. The use of other than gen-
uine Jordan Valve parts may impair their ability to serve
you. Jordan parts are held to close tolerances to eliminate
field machining and grinding (on plugs and rings) or ream-
ing (plug guide bushings).
When ordering parts, refer to the drawings at the end of
this document and reference the appropriate part name.
When ordering replacement parts, please supply the fol-
lowing information: valve model name, serial number (if
available), part name, actuator size, body material, valve
action and Cv.
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