ELEKTROGAS – TECHNICAL MANUAL
3-12
Functioning and
application
The EVRM-NA /6NA type valve is a manual reset safety valve that is normally open. A manual
operation is therefore necessary to open the valve and to reset the mechanism consenting to
maintain this state. The powering by means of line current and/or condenser discharge, induced
by the leakage detector, safety thermostat or alarm system causes driving of the mechanism
and consequent closing of the gas orifice. If energizing of the sensor persists because of the
presence of gas, the valve remains under power and does not allow reset. When the causes for
locking have been eliminated, valve must be opened manually.
Fig.1
The /6NA versions are provided with a dual-shutter system for pressure compensation. To open
the valve pull the knob for the first step, wait for pressure compensation, and then pull the knob
completely up to full resetting (from 3/4" to 6”).
This kind of device is normally installed downstream a manual shut-off valve and upstream of
the gas regulating train. Figure 2 shows a example of installation.
Fig.2
WARNING
Location and mode of installation must be in compliance with local rules in force.
Gas
detector
Solenoid valve
manual reset
Gas
network
Consumer
