Blodgett SB-6G Installation Operation & Maintenance page 14

4.0 OPERATION INSTRUCTION FOR BOILERS WITH CSD-1 CONTROLS
(Continued)
Firing Cycle
The gas valve is operated by pressure sensing devices. On the initial operation of the
boiler, steam generation should reach 11 psi in approximately 15 minutes. At this point
the "Operating Pressure" switch will open, closing the gas valve. When pressure drops
to 9 psi, the pressure switch closes, the gas valve will open and ignition should occur.
Should the pressure rise more than 14.5 psi the "Override Pressure Switch" will close
the circuit to the override solenoid valve, releasing excess steam.
Condensing Drain
A thermostat is located in the drain assembly and is activated by the temperature of
steam. The thermostat opens the cooling solenoid valve, in turn supplying water to the
drain to condense steam.
Automatic Blowdown Valve
If the unit has an automatic blowdown valve, it is activated by the main power switch.
The boiler will be drained should the main power switch be turned "OFF".
SAFETY LOCKOUT CONDITIONS
High Temperature Condition
A high temperature safety device is installed on the boiler. Should the temperature
exceed the limit of this device, the boiler will be shut down and put in a state of lockout.
The "Temperature" pilot light (red), and the "Standby" pilot (amber), will come on.
High Pressure Condition
A high pressure safety switch is installed on the boiler. Should the pressure exceed the
limit of this device, the boiler will be shut down and put into a state of lockout. The
"Pressure" pilot light (red), and the standby pilot light (amber), will come on. Should this
device fail to operate, the safety relief valve will open.
Low Water Condition
A second low water safety cut off is supplied with the boiler. Should the water level fall
below normal operating levels, this device will shut down and put the boiler in a state of
lockout. The "Low Water" pilot light (red), and the "Standby" pilot light (amber) will come
on.
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