69-0668—1 8

VR8300A CONTINUOUS PILOT COMBINATION GAS CONTROL

4. If the desired outlet gas pressure or gas flow rate
cannot be achieved by adjusting the gas control,
check the gas control inlet pressure using a
manometer at the inlet pressure tap. If the inlet
pressure is in the normal range (refer to Table 7 or
8), replace the gas control. Otherwise, take the
necessary steps to provide proper gas pressure to
the gas control.
Check Safety Shutdown Performance
WARNING
Fire or Explosion Hazard.
Can cause property damage, severe injury,
or death
Perform the safety shutdown test any time work is
done on a gas system.
1. Place the gas control knob in the PILOT position.
Main burner should go off and pilot should remain lit.
2. Extinguish the pilot flame. Pilot gas flow should stop
within 2-1/2 minutes. Safety shutoff of pilot gas
proves complete shutdown since safety shutoff
valve prevents main burner and pilot gas flow.
3. Relight pilot burner and operate system through one
complete cycle to ensure all controls operate
properly.
MAINTENANCE
WARNING
Fire or Explosion Hazard.
Can cause property damage, severe injury,
or death.
Improper cleaning or reassembly can cause gas
leakage. When cleaning, ensure that control is
reassembled properly and perform gas leak test.
Outlet Pressure
Nominal Nominal Factory Setting Setting Range
Model Type of Gas Inlet Pressure Range Step Full Rate Step Full Rate
Standard-opening Natural 5.0 - 7.0 — 3.5 — 3.0 - 5.0
LP 12.0 - 14.0 — 11.0 — 8.0 - 12.0
Outlet Pressure
Nominal Nominal Factory Setting Setting Range
Model Type of Gas Inlet Pressure Range Step Full Rate Step Full Rate
Standard-opening Natural 1.2 - 1.7 — 0.9 — 0.7 - 1.2
LP 2.9 - 3.9 — 2.7 — 2.0 - 3.0
Regular preventive maintenance is important in applica-
tions that place a heavy load on system controls such as in
the commercial cooking and agricultural and industrial
industries because:
• In many such applications, particularly commercial
cooking, the equipment operates 100,000-200,000
cycles per year. Such heavy cycling can wear out the
gas control in one to two years.
• Exposure to water, dirt, chemicals and heat can
damage the gas control and shut down the control
system.
The maintenance program should include regular check-
out of the gas control as outlined in the Startup and
Checkout section, and the control system as described in
the appliance manufacturer literature.
Maintenance frequency must be determined individually
for each application. Some considerations are:
•

Cycling frequency

. Appliances that may cycle 100,000
times annually should be checked monthly.
•

Intermittent use

. Appliances that are used seasonally
should be checked before shutdown and again before
the next use.
•

Consequence of unexpected shutdown

. Where the
unexpected shutdown is costly, the system should be
checked more often.
•

Dusty, wet, or corrosive environment.

In these environ-
ments the gas control can deteriorate more rapidly so
the system should be checked more often.
The gas control should be replaced if:
• It does not perform properly on checkout or trouble-
shooting.
• The gas control knob is hard to turn or push down, or it
fails to pop up when released.
• The gas control is likely to have operated for more than
200,000 cycles.
Table 7. Pressure Regulator Specification Pressures in in. wc.
Table 8. Pressure Regulator Specification Pressures in Kpa.