STA-RITE SR200NA Service Manual page 47

SECTION FOUR – Routine Maintenance and Professional Servicing
Combination Gas Control Valve
To Air Flow
Switch
To Air Flow
Switch
To Gas
Valve Vent
Connection for
Service
I I I I n n n n s s s s t t t t r r r r u u u u c c c c t t t t i i i i o o o o n n n n s s s s F F F F o o o o r r r r C C C C h h h h e e e e c c c c k k k k i i i i n n n n g g g g t t t t h h h h e e e e G G G G a a a a s s s s P P P P r r r r e e e e s s s s s s s s u u u u r r r r e e e e
T T T T h h h h r r r r o o o o u u u u g g g g h h h h t t t t h h h h e e e e C C C C o o o o m m m m b b b b i i i i n n n n a a a a t t t t i i i i o o o o n n n n G G G G a a a a s s s s C C C C o o o o n n n n t t t t r r r r o o o o l l l l V V V V a a a a l l l l v v v v e e e e
T T T T h h h h e e e e s s s s e e e e i i i i n n n n s s s s t t t t r r r r u u u u c c c c t t t t i i i i o o o o n n n n s s s s a a a a r r r r e e e e f f f f o o o o r r r r t t t t h h h h e e e e u u u u s s s s e e e e o o o o f f f f q q q q u u u u a a a a l l l l i i i i f f f f i i i i e e e e d d d d
s s s s e e e e r r r r v v v v i i i i c c c c e e e e t t t t e e e e c c c c h h h h n n n n i i i i c c c c i i i i a a a a n n n n s s s s o o o o n n n n l l l l y y y y ! ! ! !
D D D D o o o o n n n n o o o o t t t t a a a a t t t t t t t t e e e e m m m m p p p p t t t t t t t t h h h h i i i i s s s s p p p p r r r r o o o o c c c c e e e e d d d d u u u u r r r r e e e e u u u u n n n n l l l l e e e e s s s s s s s s y y y y o o o o u u u u h h h h a a a a v v v v e e e e b b b b e e e e e e e e n n n n
t t t t r r r r a a a a i i i i n n n n e e e e d d d d a a a a n n n n d d d d c c c c e e e e r r r r t t t t i i i i f f f f i i i i e e e e d d d d i i i i n n n n t t t t h h h h e e e e c c c c a a a a r r r r e e e e a a a a n n n n d d d d r r r r e e e e p p p p a a a a i i i i r r r r o o o o f f f f g g g g a a a a s s s s - - - - f f f f i i i i r r r r e e e e d d d d
a a a a p p p p p p p p l l l l i i i i a a a a n n n n c c c c e e e e s s s s ! ! ! !
D D D D o o o o n n n n o o o o t t t t a a a a t t t t t t t t e e e e m m m m p p p p t t t t t t t t h h h h i i i i s s s s p p p p r r r r o o o o c c c c e e e e d d d d u u u u r r r r e e e e i i i i f f f f t t t t h h h h e e e e f f f f o o o o l l l l l l l l o o o o w w w w i i i i n n n n g g g g i i i i n n n n s s s s t t t t r r r r u u u u c c c c - - - -
t t t t i i i i o o o o n n n n s s s s a a a a r r r r e e e e c c c c o o o o n n n n f f f f u u u u s s s s i i i i n n n n g g g g ! ! ! !
This appliance is equipped with an unconventional gas
control valve that is factory set with a manifold pres-
sure of –.2"wc. Installation or service must be per-
formed by a qualified installer, service agency, or the
gas supplier. If this control valve is replaced, it must be
replaced with an identical control.
The Combination Gas Valve incorporates dual shut-off
valves and a negative-pressure regulator. For proper
operation, the regulated pressure at the outlet manifold
of the valve must be 0.2"wc below the reference pres-
sure at the blower mixer inlet, and the gas valve
S S S S a a a a f f f f e e e e t t t t y y y y P P P P r r r r e e e e c c c c a a a a u u u u t t t t i i i i o o o o n n n n s s s s : : : :
Risk of fire or explosion. Improper
installation, adjustment, alteration, service, or
maintenance of the Combination Gas Control Valve
can lead to fire or explosion, causing loss of life,
personal injury, or property damage.
NOTE:
omitted for clarity; make this test with all gas piping
connected (as for normal service).
To High Side
of Differential
Pressure Gauge
To Low Side of
Differential
Pressure Gauge
Connection for
Test
4-15
The gas piping and unions have been
'VENT' tap must be connected to the Endcap/Air
Orifice as shown.
Do not attempt to adjust the gas input by adjusting the
regulator setting. The correct gas regulator setting is
required to maintain proper combustion and must not
be altered.
Verify the maximum and minimum regulated gas pres-
sures from the gas supply. These pressures must be
within the range listed on the conversion plate.
T T T T o o o o c c c c h h h h e e e e c c c c k k k k t t t t h h h h a a a a t t t t t t t t h h h h e e e e g g g g a a a a s s s s p p p p r r r r e e e e s s s s s s s s u u u u r r r r e e e e s s s s e e e e t t t t t t t t i i i i n n n n g g g g i i i i s s s s c c c c o o o o r r r r r r r r e e e e c c c c t t t t , , , , u u u u s s s s e e e e
t t t t h h h h e e e e f f f f o o o o l l l l l l l l o o o o w w w w i i i i n n n n g g g g p p p p r r r r o o o o c c c c e e e e d d d d u u u u r r r r e e e e : : : :
1. Turn off the electrical supply to the heater; turn off
the pump; turn off the manual gas supply valve to
the heater.
2. Unbolt and separate the top jacket halves.
3. Use a 3/16"hex key to remove the plug from the
'PRESSURE TAP' port on the outlet side of the
Combination Gas Control Valve.
(Continued on the next page)
Note: Your model may be
equipped with an ON-OFF
toggle switch instead of
the Gas Control Knob.