Operating instructions
59
Is field wiring loose or faulty?
Is power supply between 59 
and 61 Hz?
NO
YES
_ P _ _ _ 
Blocking Error E 4 5 
Net frequency error
Correct wiring
Is power supply circuit breaker 
loose or faulty?
Provide frequency 
stabilized power 
supply rated at 60 Hz 
+/- 2%
Replace Control 
Module
YES
YES
NO
NO
Replace circuit 
breaker
13 - TROUBLE SHOOTING
Fix the connection.
These error messages are displayed 
when the control board detects fault in 
blower motor system. 
Check wire connector to blower. 
Check connector J9 on control board is 
any connection loose? 
YES
NO
Replace blower motor. Does 
this correct the problem?
YES
NO
Boiler is operating 
properly
Replace Control Module










