Honeywell VR8205, Руководство пользователя

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68-0049—2 12
VR8205; VR4205
OPERATION • SERVICE
regulator maintains outlet pressure at the preset step rate for
several seconds. Then the regulator valve is forced fully
open by the timing diaphragm, which is operated by bleed
gas. When the low pressure regulator is fully open, the high
pressure regulator maintains the desired full-rate outlet
pressure as described for the standard regulator.
The step model requires approximately 60 seconds to
reset once the main burner goes off. If it is reenergized
within 60 seconds, it may bypass or shorten the length of
the low pressure step. The burner may relight at the full
flow rate.
WHEN THE CALL FOR HEAT ENDS
When the call for heat ends, the first automatic valve and
the second automatic valve operator close, bypassing the
regulator(s) and shutting off the main burner and the pilot.
As pressure inside the gas control and underneath the
automatic valve diaphragm equalizes, spring pressure closes
the second automatic valve to provide a second barrier to
gas flow.
Fig. 11—Position of gas control components during burner on cycle.
Service
! !
WARNING
FIRE OR EXPLOSION HAZARD
CAN CAUSE PROPERTY DAMAGE,
SEVERE INJURY OR DEATH
Do not disassemble the gas control; it contains no
replaceable components. Attempted disassembly
or repair may damage the control.
CAUTION
Do not apply a jumper across (or short) the valve
coil terminals, even temporarily. Doing so may
burn out the heat anticipator in the thermostat or
damage the DI module.
IMPORTANT: Allow 60 seconds after shutdown before
re-energizing step-opening model to assure lightoff
at step pressure.
FIRST
AUTOMATIC
VALVE
SOLENOID
CONTROL
KNOB
GAS
CONTROL
INLET
SECOND AUTOMATIC
VALVE OPERATOR SECOND
AUTOMATIC
OPERATOR
SOLENOID
SECOND
AUTOMATIC
OPERATOR
VALVE DISC
SERVO PRESSURE
REGULATOR
GAS
CONTROL
OUTLET
SECOND AUTOMATIC
VALVE DIAPHRAGM
FIRST AUTOMATIC VALVE
NOTE: SECOND AUTOMATIC VALVE OPERATOR AND
SERVO PRESSURE REGULATOR SHOWN OUTSIDE
GAS CONTROL FOR EASE IN TRACING GAS FLOW.
SLOW-OPENING GAS CONTROL HAS A GAS FLOW RESTRICTOR IN THIS PASSAGE.
M9115
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