Nu-Way PO160, Installation & Maintenance Manual

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PO Series Technical Specification Page C.14
B BB
BB
URNER URNER URNER URNER URNER
S S
S S S
EQUENCE EQUENCE EQUENCE EQUENCE EQUENCE
C C
C C C
ONTROLLER ONTROLLER ONTROLLER ONTROLLER ONTROLLER
: L : L
: L : L : L
ANDIS ANDIS ANDIS ANDIS ANDIS
& S & S
& S & S & S
TTTTTAEF AEF AEF AEF AEFA AA AA
L L
L L LAL2.25
AL2.25
AL2.25 AL2.25 AL2.25
Enlarged Detail Of Sequence Indicator
Sequence
Indicator
P
1
I
In the event of a fault condition the sequence
disc stops rotating, with the symbol appearing
above the indicator mark indicating the nature
of the fault.
If the fault leads to a lockout condition the
orange lockout indicator will be illuminated.
Symbol Lockout Fault
No
No
Yes
Yes
No
None Yes
Yes
Yes
1
Failure of one or more of the pre-start checks. Before allowing the
sequence to begin the unit carries out the following checks:
Burner Controller not in lockout position.
Air Damper Closed (proved by limit switch supplying voltage from terminal
11 to terminal 8).
Fuel Valves closed (proved by limit switch supplying voltage to terminal 12)
Fuel pressure switch, Limit Thermostat or Limit Pressure Switch all closed
(proved by continuity between terminals 4 and 5)
Interruption to sequence whilst controller waits for the air damper to drive to
open position (proved by servo motor limit switch).
Lockout caused by the failure of the air pressure switch to changeover from
the 'no air' position shortly after the pre-purge.
Lockout caused by a fault in the flame supervision circuit.
Interruption to sequence whilst controller waits for the air damper to
drive to start position (proved by servo motor limit switch).
Lockout during the pre-ignition period not marked by a symbol is
usually caused by premature flame signal.
Lockout caused by the absence of a flame signal at the end of the first safety
period (time for start flame establishment).
Lockout caused by the loss of the flame signal during normal operation.