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page no. 33 of 44
NVx Range Users, Installation & Servicing Instructions issue 6.4 Aug 2017.
Governor adjustment screw under cover cap (Honeywell
VK4105A1001B)
Fitted to the NVx 15 to 50
Governor adjustment screw under cover cap
(Honeywell VR4605AB1027)
Fitted to the NVx 60, 75, 90SF
Governor adjustment screw under cover cap (Honeywell
VK425AB1007)
Fitted to the NVx 120SF and 140SF
the burners have still not lit the control box will go to
lockout and the amber indicator light, internal and remote
lockout lights will be illuminated. To restart the ignition
sequence depress the illuminated reset button for about
1-2 seconds.
4. SHUT OFF Set the external controls to OFF or MIN.
2.6.6 Adjustments
2.6.6.1. Burner Gas Pressures
This is set for the required heat input before despatch.
In the case of Hi/Lo and Modulating units both high and
low pressures are set. Pressures should be checked in the
following manner:
2.6.6.1.1. Standard On/Off Units
1. Set external controls to ensure that the main burner is
off. Open the side access door. 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.
Compare the measured burner gas pressure to that
stated on the data plate. If necessary adjust the burner
gas pressure by turning the regulator screw anticlockwise
to decrease the pressure, or clockwise to increase the
pressure.
3. In addition it is advisable to check the gas rate using the
gas meter dial pointer. Ensure that no other appliances
supplied through the meter are in operation.
4. If required, after checking or setting the burner
pressures, the CO2 content in the flue gases can be
checked by sampling in the first section of flue fitted to the
flue outlet of the unit. Nominal CO2 values are given for
guidance in the table at the bottom of the previous page.
5. Turn off the main burner and disconnect the pressure
gauge and replace the sealing screw. Turn on the main
burner as above and test for gas soundness around
pressure test joint using a leak detection fluid e.g. soap
solution.