Hamworthy Sherborne Series, Installation, Commissioning And Servicing Instructions

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HAMWORTHY HEATING LTD
16
SHERBORNE 500001167/E
7.0 BOILER CHECKS
IMPORTANT: BEFORE PROCEEDING TO LIGHT THE BOILER, ENSURE THAT THE PRE-COMMISSIONING
CHECKS HAVE BEEN CARRIED OUT & THE RESULTS SATISFACTORY.
7.1 Boiler Gas System Leak Check (Transport & installation may cause leaks)
Switch the appliance manual gas service valve to the OFF position &
follow the procedure below. Care must be taken not to allow leak detec-
tion fluid on or near any electrical parts or connections.
To Check Appliance Isolating Valve (B)
•
Turn off the electrical power & gas to the appliance.
•
Connect the manometer to gas valve test point.
•
With A, B closed open C & monitor manometer over a 2 minute
period, a rise indicates a leak on valve B.
To Check Main Gas Valve (A)
•
Open C.
•
Open B to produce the main gas supply pressure between A & B.
•
Close B
•
System may be considered sound if over a period of 2 minutes any
drop in pressure is less than 0.5 mbar.
Note: - Main gas supply pressure - G20 - 20mbar
- LPG - 37mbar
NOTE: Allow a manometer stabilisation period of approximately 1-minute before
each 2 minute check period. Following soundness tests close valve B & remove
manometer connections & tighten test points.
7.2 Checks Prior to lighting the boiler
NOTE!
Refer to Appendix A for Natural Gas / LPG maximum gas inlet pressures for normal operation.
The following checks must be made prior to lighting the boiler.
•
Check gas supply is connected but turned to "off" position.
•
Check unions/fittings are correctly tightened & test points closed.
•
Check the ignition & probe leads are connected correctly.
•
Check flow & return sensors are correctly fitted (in the flow & return pipes)
•
Ensure the electrical mains supply is correctly connected but the boiler module isolator(s) are switched off.
•
Check all wiring loom connections such as fan or gas valve, are correct or secure.
•
Test safety thermostat by removing clip & bulb from the pocket in the front of the heat exchanger & care-
fully applying heat source to the bulb. The thermostat reset button should operate. To reset, remove the
black screw cover & depress the button, once the sensing bulb has cooled down. If satisfactory, refit the
cover & the bulb in the pocket & secure with the clip.
•
Check setting of temperature limit thermostat (Factory set at 95°C & must not be set above 100°C)
•
Check setting of control thermostat (factory set to a flow temperature of 80°C & must be re-set to suit the applica-
tion– see section 8 for controls operation)
•
Check the resistance of the hot surface igniter. This should be checked cold, using a suitable ohmmeter, by
disconnecting the igniter from the control panel cable & measuring the resistance across the pins of the 2
way connector. The reading should be between 70 & 110 ohms.
Gas System Leak Check Diagram
Test Point Location On Gas
Valve
Test Point