CleaverBrooks FLX Operation, Service And Parts Manual page 86

Chapter 6
Problem
SHUTDOWN OCCURS
DURING FIRING
MODULATING MOTOR
DOES NOT OPERATE
Excessive Rust On Tubes
Water On Base
6-4
7. Improper air/fuel ratio (lean fire).
A. Slipping linkage.
B. Damper stuck open.
C. Fluctuating fuel supply.
1). Temporary obstruction in fuel line.
2). Temporary drop in gas pressure.
8. Interlock device inoperative or defective.
1. Manual-automatic switch in wrong position.
2. Linkage loose or jammed.
3. Motor does not drive to open or close during pre-purge or close on burner shutdown.
A. Motor defective.
B. Loose electrical connection.
C. Damper motor transformer defective.
4. Motor does not operate on demand.
A. Manual/automatic switch in wrong position.
B. Modulating control improperly set or inoperative.
C. Motor defective.
D. Loose electrical connection.
E. Damper motor transformer defective.
1. Condensation of the flue gases on cool tubes is causing rust.
A Change system so return temperatures are above 120
assure water temperatures entering boiler are above 120
2. Open stack or condensate running down stack or breeching.
A. Stack should be offset. Insulate and drain stack.
3. Frequent cold starts.
A. Reset controls for less cycling.
1. A cold environment and/or intermittent firing may allow inner casing to heat up above
the condensation temperature of the flue gasses.
A. Increase temperature of the cold boiler room if possible.
B. Verify insulation is in place between inner and outer casing and replace if missing.
C. Reset controls for less cycling to allow boiler to run for longer periods of time to heat
inner casing above condensation temperature.
Troubleshooting
Solution
F or install blend pump to
°
F.
°
750-177