page no. 28 of 44
HEMNVx & HEMSL Range Users, Installation & Servicing Instructions Doc Ref M103 issue 3.6 Mar 2020.
Minimum Setting
Disconnect electrical connection to the regulator and turn
the burner back on and wait until the burner pressure has
stabilised.
Use a screwdriver to turn the slotted adjustment screw
clockwise to increase and counter-clockwise to decrease,
until the required pressure is obtained.
Reconnect high/low regulator and check high fire
pressure.
Repeat both steps if necessary and then replace cover
cap.
5. Turn off the main burner, disconnect the pressure
gauge and replace the sealing screw.
‘O’ ring
Adjustment nut (9mm)
for minimum pressure setting
Adjustment nut (7mm)
for maximum pressure setting
Cap
Shaft
6.3mm AMP terminals
1. Set external controls to ensure that the main burner is
off. Open the side access panel. Connect a pressure gauge
to the burner pressure test point on the multifunctional
control.
2. Set external controls so as to turn on the main burner
and maintain high fire. Compare the measured burner gas
pressure to that stated on the data plate.
In addition it is advisable to check the gas rate using the
gas meter dial pointer ensuring that no other appliances
supplied through the meter are in operation.
3. Repeat 2 above with external controls set to maintain
low fire.
4. If it is necessary to adjust either the high fire or low fire
pressures proceed as follows after removing the plastic
cover from the Modulating regulator.
Note: Minimum fire setting must be adjusted
first after which the high fire setting can be
set. Any adjustment of the minimum fire
setting alters the maximum setting.
Minimum Setting.
Disconnect electrical connection of modulating regulator
and turn burners back on and wait until the burner
pressure has stabilised.
Turn 9mm adjustment nut for low fire pressure clockwise
to increase and counter-clockwise to decrease until the
required pressure is obtained.
Reconnect modulating regulator and check high fire
pressure, readjust if necessary.
Maximum Setting.
Disconnect electrical connection of modulating regulator
and turn burners back on and wait until the burner
pressure has stabilised.
Push shaft gently downwards to the maximum
adjustment screw and hold there. Turn 7mm adjustment
nut for high fire pressure, clockwise to increase and
counter-clockwise to decrease, until the required pressure
is obtained. Release shaft.
Repeat both settings if necessary and then replace cover
cap.
5. Turn off the main burner, disconnect the pressure
gauge and replace the sealing screw.
Standard control for modulating burners, this MGV board
is fitted to the module and interfaces between a 0-10VDC
control signal and the modulating regulator.
Basic operation method
.
1. With the 0 to 10 signal at 0, the gas valve drive signal
will be de-energised.
2. When the input control signal goes to >2V, the gas valve
drive output will be at its maximum output value for a
preset 2 minutes.