Nu-Way MGN 2800N, Инструкция по установке и обслуживанию

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MGN 2800N HP 17
BURNER PRE-COMMISSIONING
Check both gas and electricity supplies to the burner are turned off. Remove the cover and fit a link between
terminals 2 & 3 of the low gas pressure switch. Remove the control panel cover and remove the low flame hold
link (two stage burners). Set the air pressure switch to minimum. Replace the control panel cover.
Momentarily switch on the burner and check the motor rotation, which should be anticlockwise, viewed from the
motor end.
If the direction of rotation is incorrect, please refer to Fault Finding to correct it. Switch on the burner.
Depending on the type of the control box, the burner will go through its operating sequence.
a. Immediately if it has previously been working but switch off during a normal operating cycle.
b. On pressing the reset button on the control box.
The burner motor will run. If at this stage the burner goes to lockout, please refer to the Fault Finding section
on page 23.
Check that the ignition spark is present. For actual timings refer to the Sequence Diagram and Timing Chart on
page 14.
If at this stage there is no ignition spark and the burner goes to lockout, the air pressure switch may require
adjustment. Following the safety lockout time (T3) the ignition spark should cease and the burner go to lockout.
Switch off the electrical supply to the burner.
Remove the control panel cover and refit the Low Flame Hold Link. Replace the control panel cover.
Remove the temporary link between terminals 2 & 3 of the low gas pressure switch and refit and secure the
cover.
Safety system proved. Burner commissioning can proceed. Switch off the power to the burner.
BURNER COMMISSIONING
Check that the appliance is in a proper and safe state to be fired (for instance, is there water in the
boiler?).
Set the appliance controls to call for heat.
Check for Valve Closure (Burners Without Valve Proving System)
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All gas train assemblies are fully tested for function and valve security before despatch.
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A soundness test of the gas valve is difficult without specialised pressure testing equipment.
However, the following check can be performed to measure the security of the valve system.
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Ensure that the gas supply pipework to the burner gas line is sound and that gas is available at
the required inlet pressure for the burner. Fit a manometer to the test point at the inlet to the
upstream main safety valve. Open the main upstream manual valve for a few seconds and then
close and secure the gas supply.
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The space between the upstream manual valve and the gas train inlet should now be filled with
gas at inlet pressure. If the pressure remains stable over one minute then this indicates that the
valve train is secure, but not necessarily in the main valve. If the pressure decreases then this
indicates that the main and one other valve is leaking or that there is a leak between the upstream
manual valve and the main gas valve.
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Secure the upstream test point and fit the manometer to the test point situated between the main
and control valves.
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Check the reading on the manometer, this should now show near atmospheric pressure. Open
the upstream manual valve and look for an increase in pressure over one minute. If no rise is
detected, this indicates that the main valve is closing correctly.
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The next stage of the procedure requires the burner to be momentarily started. Open the
upstream manual valve and switch the burner on. The burner will attempt to start and will either
establish a flame (in which case switch the burner off immediately) or “lockout”. Isolate the
electricity supply.
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The space between the main and control valves should now be filled with gas at near inlet
pressure. If the pressure remains stable over a period of one minute, this indicates that the valve
system is secure.
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If the pressure decreases, this indicates that there is a leak in the valve system and the valve train
assembly should be returned to the factory for a full examination. Remove the manometer and
close the test point.