Roberts Gorden UHD[X][S][R] 125 User Manual

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 UHD L
OW
 P
ROFILE
 D
UCT
 F
URNACE
 I
NSTALLATION
 O
PERATION
 
AND
 S
ERVICE
 M
ANUAL
24 
Figure 13: Automatic Burner Control Sequence
Figure 14: Gas Valve 
Burner Sequence for Ignition Control
Flame Signal
Start Gas Valve
Ignition Spark
Thermostat 24 V
SHUT DOWN
RUN
START
 ts = 10 Seconds
Signals Output By Control
Required Incoming Signals
Flue Blower
Pressure
Switch
P
C
NO
NC
30 Seconds Purge*
*Purge time begins at pressure switch change over.
30 Seconds Post 
If at any stage the flame fails, the control will retry 
for ignition. The control has four trials for ignition 
before a one hour lockout.
½PSI
IN
C
ON
OFF
Regulator
Outlet
Pressure
Gas Inlet
Inlet Pressure
TOP VIEW
END VIEW
Description
Part Number
  Gas Valve NG
90032505
  Gas Valve LP
90032506