® U.S. Registered Trademark
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INSTALLATION INSTRUCTIONS
69- 1304
VS8420C,M
Millivolt Gas Valve
APPLICATION
The VS8420 Millivolt Gas Valve is compact and has a
low capacity. The design makes it ideal for central heat-
ing, fireplace, and space heating applications.
The VS8420 Millivolt Gas Valve is approved in accor-
dance with existing European standards.
SPECIFICATIONS
Main Gas Connection:
Valve:3/8" ISO 7/1 internal thread for 12 mm outside
diameter tube.
Inlet connection at inlet side or at bottom.
Outlet connection at outlet side or at bottom.
Pilot Gas Connection and Flow:
Connection Size: M10 x 1 for 4 or 6 mm outside diame-
ter tube. At inlet side or at bottom.
Flow: Adjustable from 0.014 m3/h air at 35 mbar inlet
pressure to 0.105 m3/h at 7.5 mbar.
Thermocouple and Pilot Threads:
Metric and UNS.
Thermocouple connection: M10 x 1 at bottom. Optional at
the outlet side with use of a thermocouple re-route.
Ambient Temperature Range: 0°C to 80
°
C (32°F to
175°F).
Maximum Inlet Pressure: 60 mbar (24 in. wc)
Pressure Regulation (Standard Regulator):
Servo regulator with adjustable outlet pressure; in
accordance with EN 88, class C.
Natural Gas: 9 mbar, typical.
LP: 27 mbar, typical.
Regulator Adjustments (Standard Regulator):
Natural Gas: 7.5 mbar to 12.5 mbar field adjustable.
LP: 20 mbar to 30 mbar field adjustable.
In appliances where no regulation is required, the pres-
sure regulator must be blocked by turning the pressure
regulator adjustment screw fully down. The regulator
will then be set at 30 mbar.
Voltage: VS8420: 750 mV operator, 30 mV thermocou-
ple.
Approvals: European Community (CE) Certificate: CE-
0063AU1270.
Other Features:
Pressure Tap: 9 mm outside diameter at inlet and outlet
sides in accordance with EN 126.
Screen: Fine mesh inlet screen.
Interrupter (ECO) Connection: 6.3 mm tab connectors.
Piezo Sparker: Optional piezo sparker.
INSTALLATION
When Installing this Product...
1.
Read these instructions carefully. Failure to follow
them could damage the product or cause a haz-
ardous condition.
2.
Check the ratings given in the instructions and on
the product to make sure the product is suitable
for your application.
3.
Installer must be a trained, experienced service
technician.
4.
After installation is complete, check out product
operation as provided in these instructions.
WARNING
Oxygen Depletion Hazard.
Can cause injury or death due to asphyxia-
tion.
Use only vented gas valve models on vented
appliances. Use only unvented gas valve mod-
els on unvented appliances.