SYMPTOM WHAT TO CHECK
a.
Lighting procedure. See the "Operation" section of
this manual.
b.
For defective switching across either the water
level control or the pressure switches by testing for
continuity. Replace defective units. (Ref. 22 or 23,
24).*
c.
For defective gas valve and replace if necessary
(Ref. 10).*
Pilot light does not stay lighted.
d.
Pilot gas adjustment and readjust, if necessary
(Ref. 17).*
Generator builds up pressure, shuts down, and fails to
come on again.
a.
Pilot light. If out. see "Operation" section of this
manual.
a.
Pilot light. If it is out, see the "'Operation" section
of this manual.
Main burners will not light.
b.
Gas valve. Replace, if defective (Ref. 10).*
a.
That electric power is being supplied to the unit.
b.
For 115V input to the control module (Ref. 31)*
c.
For a 24 V supply at the transformer (Ref. 31).'
d.
For 24 V between pins "2" and "4" of the control
module (Ref. 25).'
e.
Voltage of supply to the igniter by removing the
igniter plug from the receptacle of the control
module and reading voltage across the pins of the
igniter receptacle (Ref. 25).* If 115 V is not
present, replace the control module. (Ref. 25).*
C. Model NGB/Eonly
Glow coil does not heat.
f.
Voltage across the terminals of the main gas valve
solenoid. If 24 VAC is present. replace the gas
valve assembly. If not, replace the control module.
(Ref. 10 and 25)*
a.
Voltage across the terminals of the gas valve
solenoid. If 24 VAC is present, replace the gas
valve assembly. If not, replace the control module.
(Ref. 10 and 25).*
b.
Ground connections of module terminal. "12"
(green wire) for firm attachment (Ref. 25)*
c.
Flame sensing probe and wire "11" (blue) for a
short to ground. If necessary, correct the short or
replace the probe (Ref. 20).*
d.
For a short to ground at the 24 V source. If the
transformer is shorted, remove the short and
replace the control module. (Ref. 31 and 25).*
Burner does not come on. but the glow coil
heats.
e.
After the transformer has been replaced, check the
flame sensing function. If flame sensing is not
working. reverse the leads of either the 115 V or
24 V side of the control transformer (Ref. 20 and
31).*
14
Содержание NGB
Страница 18: ......
Страница 20: ......
Страница 22: ...For NGB 2 NGB 2 E Made After August 7 1991...
Страница 23: ...Electrical Schematics For NGB 2 made between January 1 1988 and August 7 1991...
Страница 24: ...Electrical Schematics For NGB NGB E made before January 1 1988...
Страница 25: ...Wiring Ladder Diagrams...