Datasheet Content
VMRNA
Automatic vent valve
for gas appliances
3/4”- 1”½
delta-elektrogas.com EE169 - 1118
ELEKTROGAS – Technical Sheet EE169 - 1118
VMRNA
Contents
Description .. 2
Features .. 2
Functioning and application . 3
Technical specifications 4
Gas flow chart .. . . 5
Ordering information . 6
Special versions . 7
Options .. . . 7
Standards and approvals .. . 7
Description The VMRNA type is an automatic vent valve for gas appliances. It is suitable for discharging
excess or leakage gas into relief lines.
Features VMRNA valve is a reverse acting solenoid valve: when de-energized, the valve is open (N.O.
normally open).
The valves are made of aluminum alloy with connections from 3/4” or 1”½. Pipe connections
meet group 2.
Sealings are made of NBR-based rubber certified for use with air gas (EN 549). Suitable for
use with air and non-aggressive gases included in the 1st, 2nd and 3rd families (EN 437). Special
versions for aggressive gases (e.g. biogas).
Qualified for continuous service (100% ED).
Provided with G1/4 pressure gauge on two sides in inlet chamber to connect manometers,
pressure switches, or other gas equipment.
Provided with G1/8 connection to fit an open position indicator switch (see PCS datasheet - This
device shall be ordered separately).
VMRNA valve can be integrated in Elektrogas VMM valve, resulting in a very compact system
(see VMM datasheet for details).
All components are designed to withstand any mechanical, chemical and thermal condition
occurring during typical service. Effective impregnation and surface treatments have been used
to improve mechanical sturdiness, sealing and resistance to corrosion of the components.
Valves are 100% tested and fully warranted.
WARNING
This control must be installed in compliance with the rules in force.
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ELEKTROGAS – Technical Sheet EE169 - 1118
Functioning and
application
The VMRNA type valve is a vent valve
for relief line. When it is de-energized,
the spring pushes on the magnetic core
and the disc is open, hence gas can flow
to relief line. This device is usually
integrated in burning system: when the
system is de-energized, upstream safety
shut off valves are closed, while vent
valve is open, so that fuel gas inside
pipe can be discharged in a safe area.
In case of leakages of shut off valves,
gas goes to relief line in a safe
condition.
When the system is powered, vent valve
closes while the main shut off valves
open, hence fuel can flow to burner.
Fig. 1 shows a scheme of VMRNA
valve.
Fig. 1
This kind of valve is usually installed as safety device in gas trains, for industrial applications
and gas firing systems. Fig. 2 shows an example of installation, in combination with other
Elektrogas devices.
Vent valve
VMRNA Safe
with open discharge
position switch area
Pressure PCSRA
regulator with
filter
RF Pressure
Ball gauge Pressure
Valve switch
VSG PSG
Gas Burning
network system
Safety Safety
Fig. 2 shut off valve shut off valve
VMR VML
WARNING
Location and mode of installation must be in compliance with local rules in force.
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ELEKTROGAS – Technical Sheet EE169 - 1118
Technical
specifications Tab. 1
Internal threaded ISO 7-1 Rp3/4 - Rp1½
Connections
or ANSI-ASME B1.20 3/4”NPT – 1½”NPT (special ver.)
230 VAC 50/60 Hz
110 VAC 50/60 Hz 24V AC/DC
Voltage
500mbar (7psig) 200mbar (3psig)
Max. operating pressure
or or
6bar (90psig) - only ¾”-1” 2bar (30psig) – only ¾”-1”
Voltage tolerance -15% to +10%
Power consumption 35W
Ambient temperature -15°C / +60°C (+5°F to +140°F)
Opening and closing time < 1 second
Protection class IP54 (EN 60529) - optional IP65
Terminal box: M20x1,5 - 2,5 mm2 max.
Cable gland and wire section or ISO plug (optional): PG9 - 1,5 mm2 max.
Materials in contact with gas Aluminum alloy, Brass, Stainless steel, Plated steel,
Anaerobic adhesive, Nitrile rubber (NBR), Fluoro
elastomer (FPM), Polytetrafluoroethylene (PTFE)
Fig. 3
Tab. 2
A B C D Weight
Model Connection
(mm) (mm) (mm) (mm) (Kg)
VMRNA2.. ¾” 83 95 151 174 2,9
VMRNA3.. 1” 83 95 151 174 2,9
VMRNA35.. 1”¼ 115 152 178 211 4,0
VMRNA4.. 1”½ 115 152 178 211 4,0
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ELEKTROGAS – Technical Sheet EE169 - 1118
Gas flow chart
Fig. 4
Formula of conversion Tab. 3
from air to other gases Gas type Specific gravity
1.25
ρ k=
[Kg/m³] ρGAS
VGAS = k ⋅ VAIR 1 - Natural gas 0,80 1,25
2 - LPG 2,08 0,77
3 - Air 1,25 1,00
Standard conditions: 15°C, 1013 mbar, dry
When the flow read on the diagram is referred to operating pressure instead of standard
conditions, the pressure drop ∆p read on the diagram must be multiplied for the factor:
(1+ relative pressure in bar)
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ELEKTROGAS – Technical Sheet EE169 - 1118
Ordering Information
Tab. 4
VMRNA 2 -5 -
Valve type VMRNA
Connections size
2 = ¾”
3 = 1”
35 = 1”¼
4 = 1”½
M = integrated in VMM 1”¼-3” (*)
Supply voltage and operating pressure
-5 = 230V AC 500mbar
-60 = 230V AC 6bar (only ¾”-1”)
-5.B = 110V AC 500mbar
-60.B = 110V AC 500mbar (only ¾”-1”)
-2.C = 24V AC/DC 200mbar
-20.C = 24V AC/DC 2 bar (only ¾”-1”)
Special version
N = NPT connection and 120V AC voltage
J = version for bio gas
Example: VMRNA2-5.B : valve 3/4”, 110V AC, 500mbar
(*) Pictures below show a VMM valve assembled with an integrated VMRNA element:
VENT LINE
TO BURNER
VMM…
