Absolute ABS-1500 - Gas; Air Ratio Control; Gas Valve Adjustment

Absolute Boilers ABS 1500-2000-2500-3000-4000
52
6.3 Gas / air ratio control
The boiler has a pressure dierential gas/air ratio control. This gas/air ratio control maintains the correct balance of gas
and air quantities to the burner at a constant level under variable loads. This ensures clean and reliable combustion and
high part load eciency across the entire load range. Minimum airow is monitored before a start by an air pressure
sensor.
6.4 Gas valve adjustment
WARNING
Adjustments shall only be performed by a service representative specify trained and certied by Innovative Industrial
Inc. Verify proper operations after servicing.
CAUTION
For high altitude adjustment ( greater than 2,000 feet above sea level) see page # 89
The gas valves are located directly underneath the pre mix blower assembly. The gas valve is mounted on a adjustable
stand that fully supports the gas valve.
Check the combustion using a calibrated combustion analyzer and adjust the fuel-air ratio of the valve being used
according to the procedures below.
To adjust High re:
Required tools: Flat head screw driver and combustion analyzer.
Start the boiler and observe the proper operating parameters for the system. Set the boiler to high re, to achieve
maximum ring rate of the boiler. Check combustion readings using the combustion analyzer. If combustion readings
are not within the range specied, adjust as follows,
A- Open the front panel of the boiler
B- Locate the Karl Dungs gas valve
C- Adjusts the orice adjustment screw, located on the downstream side of the gas valve., into the direction indicated
on the sticker to either increase or decrease the ow of natural gas. Increasing the gas ow decreases the
combustion exhaust O2., while decreases the natural gas ow increases the combustion exhaust O2. Note, There
will be a slight delay of 30 seconds from the time the adjustment is made until the gas combustion reads alter. It
is best to make small adjustments of 1 indication marker every 30 seconds to allow the combustion to stabilize
before making further adjustments. When desired adjustments are complete, do a nal test and adjust low re if
necessary.