CleaverBrooks CBLE, Operation And Maintenance Manual

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750-91 (revised 2009)
Model CB-LE Packaged Boiler Manual 1-11
1.6 — IFGR Components
1.6.3 — Over-Travel Mechanism
The over-travel mechanism has two functions. It allows the linkage to pass through the front door, and it allows
jackshaft rotation to exceed (over-travel) IFGR linkage movement. A set of springs allows the linkage to stay in a
fixed position while the jackshaft rotates.
1.6.4 — Fuel Change-Over Linkage
When a boiler is equipped to fire either gas or oil (dual fuel boilers), and the required NO
X
levels are below 60 ppm
on natural gas, a dual linkage arrangement is used to provide the different recirculation rates required for each fuel.
Two jackshaft drive arms are provided, one for oil and one for gas. The linkage is manually connected to the appro-
priate arm, based on the fuel being used.
On dual fuel boilers with two jackshaft drive arms, as defined above, a proximity switch is used to prove that the
correct linkage connection is made. (Refer to the wiring diagram provided with the boiler.)
FIGURE 1-8.
Damper Linkage