Technical information

GAS SOLENOID VALVES
Model SIT 840 (single stage)
31
Mo
del SIT 843 (two stage)
PM
Main i
n
let pressure test point
PV Head pressure test point
RP Pressure adjusting screws
RP1 Cross cut screw low fire adjuster
RP2 Hexagonal screw high fire adjuster
GAS CONVERSION
The heaters are supplied ready for use with (G20) Natural Gas set as per the table below. Conversion kits are available
from the manufacturer
Natural Gas H (G20)
TYPE 1 2 3 4 5 6 7
Number of injectors 1 1 1 1 2 2 4 N°
Diameter of injector 310 410 480 555 500 540 450 mm/100
Gas supply pressure 20 mBar
Head pressure high fire 12,0 13,0 13,0 13,0 10,0 13,0 10,5 mBar
Head pressure low fire (two stage–dual
power)
6,0 7,0 6,5 6,5 7,0 6,5 5,0 mBar
BEFORE CHANGING INJECTORS ENSURE GAS SUPPLY IS ISOLATED
To convert to Propane G31
1. Change injectors
2. Adjust the inlet gas pressure
3. Adjust the head pressure gas
4. Fit primary air diaphragm (if required)
5. Fit adhesive label indicating gas type
6. Ensure settings are correct as per manual.