Gas Valve Fig, Expansion Vessel Fig | Potthof & Co 28kw, 24kw, 33kw

Sensing Pipe

Power Lead

Earth Lead

Gas Feed

Elbow

Fig. 103

Venturi Inlet

Pipe

Gas Valve

Throttle

Adjustment Screw

14.0Changing Components

14.24Gas Valve (Fig. 103)

IMPORTANT: After replacing the valve the CO2 must be checked and adjusted as detailed in Section 15.0 Setting the Gas Valve. Only change the valve if a suitable calibrated combustion analyser is available, operated by a competent person - see section 13.1.

1.Turn the gas cock off and undo the nut on the gas feed elbow under the boiler.

2.Remove the screws securing the gas valve to the boiler bottom panel.

3.Pull off the power lead, earth lead and sensing pipe.

4.Undo the nut on the gas pipe at the gas/air inlet and the gas valve. Remove the pipe, taking care not to lose the sealing washers. Remove the valve.

5.Reassemble in reverse order, ensuring that all seals are in place and the injector is fitted.

NOTE: To assist the boiler to light prior to final setting, use a suitable hexagon key to wind out the Throttle adjustment screw until it is flush with the valve body, then turn the screw 4 full turns clockwise (Fig. 103a). If the boiler will not light, or the correct CO2 cannot be achieved contact the ‘heateam’ technical helpline.

Retaining Bracket

Boiler Chassis

Fig. 104

Fig. 103a

Expansion Vessel

Lock Nut

14.25Expansion Vessel (Fig. 104)

1.Drain the primary circuit and undo the nut on the vessel connection pipe.

2.Undo and remove the locknut securing the vessel spigot to the boiler air box.

3.Remove the bracket and vessel from the boiler.

4.Locate the retaining bracket on the upper flange of the vessel and fit to the boiler.

5.Reassemble in reverse order.

50© Baxi Heating UK Ltd 2012

Image 50

Potthof & Co 28kw, 24kw, 33kw manual Gas Valve Fig, Expansion Vessel Fig

Contents

Installation & Service Instructions Natural Gas Benchmark Scheme Installer Notification Guidelines Scheme Members only Codes of Practice refer to the most recent version Important Installation, Commissioning, Service & RepairLegislation Preparation Safe Manual HandlingGeneral Technique Contents Description Contents of PackIntroduction Expansion Vessel Automatic Air Vent General LayoutLayout Circulation Pump Drain Off Point Frost Protection Mode Central Heating Mode FigDomestic Hot Water Mode Fig Appliance Operation Technical Data Gold Combi 24, 28 & 33 HE a Dimensions and Fixings Central Heating Circuit System DetailsInformation Bypass Expansion Vessel Central Heating only Safety Pressure Relief Valve FigSystem Filling and Pressurising Fig Hard Water Areas Domestic Hot Water Circuit FigShowers Clearances Figs Site RequirementsLocation At least Gas Supply Site RequirementVentilation of Compartments Electrical Supply Per Metre PerPipe run Minimum Fall Run 500mm min Minimum Fall50mm per Run Minimum fall Below windows or openings on pitched roofs 2000 Plume Displacement KitFlue Likely flue positions requiring a flue terminal guard Flue Options Total equivalent length = +B+C+2x90Bends Total Equivalent Length = +B+C+1x90Bend Telescopic Flue inc. elbow Flue AccessoriesKey Accessory Size Code No Air Duct Connection Flue Duct Connection Boiler Adaptor Twin Flue Duct AdaptorTwin Flue Connection Flue Trim Flue DimensionsFor Roof Terminals Terminal Guard Fig Plume Displacement Plume Displacement Kit Fig Example 28/33Determining Permissible Lengths Elbow 30mm 50mmGeneral Fitting Notes Using a suitable bit e.g mm, drill through Elbow to allow the flue to be installed as shown60Ø extension piece. It must be secured using two Extension and outlet. Secure using two of the screws Flushing InstallationUnpacking & Initial Preparation After considering the site requirements Fitting the Filling Loop Kit Condensate Drain see section Fitting the Safety Pressure Relief Discharge Pipe FigFitting The Boiler Tighten all the connections Ensure Elbow is fully engaged into Boiler Adaptor Fitting The FlueWall Thickness Flue Elbow Wall Thickness Waste Flue Ensure Extension is fully engaged into Boiler Adaptor Inner Flue Support Bracket25mm Extension Cut End Terminal Block Cover Cable Clamp Making The Electrical ConnectionsPreliminary Electrical Checks Commissioning the Boiler Selector Switch DisplayCommissioning Screw Pump Automatic Air Vent Check the Operational Working Gas Inlet Pressure Temperature Control Selector Switch DisplayTemperature Control Gas Pressure Test Point Gas Valve It is necessary to set the boiler to ‘Calibration Mode’ Setting the Timer Case Front Panel Facia Panel CompletionCompletion Annual Servicing Inspection Servicing13 .1 Annual Servicing Electrode Position 10 ±1 Spark and Sensing Electrodes Fig Changing ComponentsIgniter Fig Injector Fig Fan FigVenturi Fig Gasket Venturi Injector Cover Gas Inlet Pipe Fan Collector Extension Piece Burner FigInsulation Fig DHW Temperature Sensor NTC Fig Central Heating Temperature Sensor NTC FigSafety Thermostat Fig Flue/Heat Exchanger Thermostat Sensor Fig Automatic Air Vent Fig Pump Head Only FigPump Complete Fig Pressure Relief Valve Fig Pressure Gauge FigsHall Effect Sensor Fig Diverter Valve Motor Unit & Assembly Fig Plate Heat Exchanger Fig Selector Switch Fig 14.22 P.C.B. Fig Gas Valve Fig Expansion Vessel Fig Flue Adaptor Test Point Plug Analyser Probe Setting the Gas ValveSetting the Gas Valve CO2 check CO2 should be 8.4% ± Reduce CO2 Illustrated Wiring Diagram Electrical 426 Short Parts ListShort Parts List 315316 311 404419 422 400 415 Error Codes Fault FindingInitial Fault Finding Checks Reset position for 5 seconds Error 133 flashingGo to section ‘A’ Turn the selector switch to Pump runs Open DHW tap fully Error 133 flashing Go to section ‘I’Turn Domestic Hot Water Close DHW tap Fan jammed or faulty winding Replace PCB PCB X3 connector terminals 3Switch terminal Replace water Gas at burner Check wiring Viewing WindowReplace sensor or PCB E28 Replace gas valve Replace sensor Replace safety thermostatReplace PCB Is there 230V at Pages for Notes Pages for Notes GAS Boiler System Commissioning Checklist Service Record Potterton