Reznor EURO-C 4000 RJL, Instruction Document

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Euro-C 4000 RJL-GBEN 15/26
5.7.2 Modureg V7335A 2000 series modulation
system
Figure 9: Modureg V7335A
Legend :
1 : Shaft
2 : Adjustment screw (7mm) for maximum
pressure setting
3 : Adjustment screw (9mm) for minimum pressure
setting
4 : “O” ring
5 : 6.3mm AMP terminals
6 : M5 pressure feedback connection
The Modureg V7335A 2000 Series Modulating
gas pressure regulators are an optional addition
which can be used on "Honeywell"
Multifunctional gas controls for modulating the
burner gas pressure for firing over the range 50%
to 100% of the nominal high fire burner rate.
Two model types are used dependant on the gas
type. They are identified Grey cover = Natural
gas, outlet pressure range 1,5 - 20,0 mbar.
Yellow cover = Propane/Butane gas, outlet
pressure range 4,0 - 37,0 mbar
(1)
Caution:
Reznor air heaters must be controlled so that
burner start-up takes place in the high fire
(100%) mode.
Modureg gas pressure regulators require to be
powered by a maximum 24 V DC voltage over
the range 15 - 165 mA maximum. Maximum
outlet pressure occurs at the high set point value
(high fire). Minimum outlet pressure occurs at
low set point value (low fire). The power signal
may be obtained from a system amplifier which
may be an integral control within the appliance
or, from a remote control system designed to
provide the required controlling voltages.
Adjusting the V7335A Regulator
Refer to figure 9.
To check the minimum or low fire and maximum
or high fire pressures for limits of modulation use
the following procedures.
Fit a manometer to appliance burner pressure test
point.
Important :
allow time for gas pressure to stabilize before
making adjustments.
To Set Minimum (low fire) 50% or 30% rate (see
table)
1. Remove regulator cover cap;
2. Disconnect electrical connection to the
regulator coil;
3. Energize operator, set control in operation
and wait until outlet pressure is recorded on
manometer;
4. Use a 9 mm wrench to turn the minimum
rate adjustment screw clockwise to increase
or counter-clockwise to decrease the
minimum pressure setting
The minimum pressure setting must be adjusted
first, because any adjustment of the minimum
pressure setting influences the maximum
pressure setting.
To set Maximum (high fire) 100% rate
1. Follow point 1 above. Connect electrical
connection to the regulator coil and ask for
maximum heat;
2. Using a 7 mm wrench to turn the maximum
adjustment screw clockwise to increase or
counter-clockwise to decrease the maximum
pressure setting to the value stated on the
appliance data plate;
3. Replace cover cap, re-wire coil in circuit;
4. Operate burner several times in high,
intermediate and low pressure modes and
check performance on the manometer.
FAULT FINDING “MODUREG” OPERATION :
follow setting procedure for fault finding
1. Minimum or Low Fire unobtainable :
- Ambient temperature too high in location
of regulator max 70°C;
- Check input voltage to coil,
Zero volts is low fire mode, shaft out;