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Type 1805P
D100675X012
Instruction Manual
Form 5088
October 2009
Type 1805P Pilot-Operated Relief Valve
Failure to follow these instructions or
to properly install and maintain this
equipment could result in an explosion
and/or fire causing property damage and
personal injury or death.
Fisher
®
regulators must be installed,
operated, and maintained in accordance
with federal, state, and local codes, rules
and regulations, and Emerson Process
Management Regulator Technologies,
Inc. instructions.
If the regulator vents gas or a leak
develops in the system, service to the
unit may be required.
Failure to correct trouble could result
in a hazardous condition. Call a gas
service person to service the unit. Only
a qualified person must install or service
the regulator.
Introduction
Scope of the Manual
This manual describes and provides instructions for
the installation, adjustment, maintenance, and parts
ordering information for the Type 1805P pilot-operated
relief valve. Instructions and parts lists for any other
Fisher equipment mentioned in this instruction manual
are found in separate manuals.
Description
The Type 1805P pilot-operated relief valve is used to
provide protection from overpressuring a downstream
system. This relief valve is suitable for service on
natural gas, air, propane, or any other operating
!
WaRnIng
Figure 1.
Type 1805P Pilot-Operated Relief Valve
medium not corrosive to the internal parts. Very little
build-up over the set pressure is required for the main
valve to go wide-open for maximum relief capacity.
Smooth opening action minimizes system pressure
surges during emergency action.
Specifications
Some of the specifications for a given relief valve as
it comes from the factory appear on the nameplate
attached to the Type 1805 main valve spring case.
Other specifications appear on the Type 6358B pilot
spring case.
W6913
