Potterton SIRIUS FS, Installation & Servicing Instructions Manual

Page 1: ...hydraulic and flue connections Easier to connect and less space needed for working access Compact dimensions and small footprint Requires less space for installation Built in boiler control User friendly control panel includes operation status weather compensation timer for heating and DHW fault diagnostics and where relevant cascade operation Controls can be programmed to work with solar thermal ...

Page 2: ...experts can guide you through building regulations legislation and building service engineering standards Our dedicated sales team is never more than a phone call away Reliability Our boilers are all factory tested before sale and we will commission them for you to make sure they work reliably and efficiently We also offer parts and labour warranties for extra peace of mind Efficiency Our modulati...

Page 3: ...ng the boiler 14 4 3 Power connection requirements 16 4 4 Requirements for heating circuit water 16 4 5 Hydraulic pump requirements 18 4 6 Application examples 20 5 0 Installation 5 1 Water connections to low temperature circuits 23 5 2 Condense connections 23 5 3 Electrical connections 24 5 4 Installing room and outside sensors 29 5 5 Flue and ventilation 33 5 6 Gas connections and tightness test...

Page 4: ...Removing and changing components 52 7 4 Component parts list 61 7 5 Component illustrations 63 7 6 Recommended parts list 66 7 7 Fault code table 69 Potterton Commercial s policy is one of continuous improvement and therefore the information in this manual whilst correct at the time of publication may be subject to revision without prior notice ...

Page 5: ...precise gas air mixture throughout the full modulation range A common combustion air intake manifold takes air from the boiler room type B23 An air non return valve gas mixing system is integrated into the air gas mixture supply of each burner to ensure that flue products cannot contaminate the air supply when the other burner is not in operation A separate electronic management system monitors th...

Page 6: ...ife CAUTION Indicates a potentially dangerous situation for the boiler and the environment INFORMATION Suggestions to assist the user in implementing instructions in this guide ADDITIONAL READING Reference to additional information in other documents 1 3 FOR WHOM IS THIS MANUAL INTENDED This manual is intended for the heating specialist who installs commercial industrial heating plant and equipmen...

Page 7: ...ncerning the use of it by a person responsible for their safety Children should be supervised to ensure they do not play with the boiler 2 1 3 Engineer Competency The installation adjustment servicing of this boiler must be carried out by a competent person In the UK by a Gas Safe Registered Engineer and in IE by a RGII Registered Gas Installer and installed in accordance with current standards an...

Page 8: ...ance I E E Regulations for the Electrical Equipment of Buildings The installation of the appliance must be in accordance with the relevant requirements of Health and Safety at Work act 1974 Building Regulations 2010 Electricity at Work Regulations 1989 Management of Health and Safety at Work Regulations 1998 Manual Handling regulations 1992 Model Water By Laws 1986 BS 7671 1992 Requirements for El...

Page 9: ...CLASS 5 MAX WATER PRESSURE 6 bar MAX OPERATING TEMPERATURE 90ºC POWER SUPPLY 230V 50 P I N CODE 0558CP37 COUNTRIES OF DESTINATION GB IE Manufactured by Malvern Boilers Limited Year Serial No 2015 ADJUSTED FOR G20 20 m 2H 2 4 CE MARKING There are two data plates located on the appliance One is mounted on the inside of the front LH side panel which becomes visible when the front door panel is remove...

Page 10: ...lue Ø180mm Low Voltage Cable Entry 230V Cable Entry 1550 1625 Wiring Centre Access panel Remove Door to allow access for pallet truck from front Remove Base Trim x2 to allow access for pallet truck from side 1 5 BSP Female DN40 0 5 BSP Female x2 DN15 1465 1405 692 1466 1506 258 356 1341 1405 86 561 192 1011 346 590 Gas 2 BSPT DN50 Male Flow 2 5 DN65 PN6 Return 2 5 DN65 PN6 Thermal Fuse Access pane...

Page 11: ...5 346 590 Rear pallet truck opening 230V Cable Entry Low Voltage Cable Entry 246 1173 566 1620 1557 356 Flow 3 DN80 PN6 Return 3 DN80 PN6 Gas 2 BSPT Male DN50 86 1 5 BSP Female DN40 0 5 BSP Female x2 DN15 Wiring Centre Access panel Remove Door to allow access for pallet truck from front Remove Base Trim x2 to allow access for pallet truck from side 1474 1405 1466 1550 1625 692 1506 258 ...

Page 12: ...heat output net 108 1 108 6 Seasonal Efficiency part L2 CV gross 97 0 97 3 Operating pressure min normal max bar 1 0 4 0 6 0 1 0 4 0 6 0 Max permitted flow temperature o C 90 90 Flow Return connections Flange size DN65 PN6 DN80 PN6 Minimum flow rate m3 h 6 75 9 0 Electrical Electrical supply voltage Hz V Hz 230 50 230 50 Minimum power consumption A W 0 1 24 0 1 24 Maximum power consumption A W 1 1...

Page 13: ...5699 95 786 20 12488 100 677 25 10000 105 586 30 8059 110 508 35 6535 115 443 40 5330 120 387 3 3 2 1K Sensor outside temperature sensor Temperature o C Resistance Ohms Temperature o C Resistance Ohms 20 7578 12 1690 15 5861 13 1621 10 4574 14 1555 5 3600 15 1492 4 3435 16 1433 3 3279 17 1375 2 3131 18 1320 1 2990 19 1268 0 2857 20 1218 1 2730 21 1170 2 2610 22 1125 3 2496 23 1081 4 2387 24 1040 5...

Page 14: ...Sirius FS 12 GB IE 3 4 WIRING DIAGRAM PCB 1 ...

Page 15: ...Sirius FS 13 GB IE 3 4 WIRING DIAGRAM PCB 2 ...

Page 16: ... taken to protect the boiler from damage and prevent any extraneous matter from being stored on or around the boiler See BS 6644 Clauses 4 5 and 6 for details Any combustible material adjacent to the boiler must be so placed and shielded as to ensure that it s temperature does not exceed 66ºC There must be easy access to the plant room and boiler at all times The boiler must be located in an area ...

Page 17: ...Sirius FS 15 GB IE 4 2 1 Space Requirements Model Dimension 400 525 A 800mm 800mm B 600mm 600mm C 400mm 400mm D 600mm 600mm E 600mm 600mm ...

Page 18: ...ecessary to thoroughly clean out the old system first This is best achieved by using a suitable cleaning solution If cleansing of the existing system is not possible e g very old or large systems it is recommended that this system water is separated from the boiler system by means of a secondary heat exchanger Please ensure you have considered the following before installation of the new boiler If...

Page 19: ...e supply water should be compared at regular intervals If the Chloride value of the system water is considerably higher than the supply value this would indicate that there is system leakage and water is being lost to evaporation This will result in Chloride concentration and premature boiler failure if left untreated If Chloride concentration levels have exceeded 200mg l the system should be flus...

Page 20: ...operation has stopped Failure to ensure minimum water circulation when the burners of the boiler are in operation may result in premature heat exchanger failure A system which proves the operation by means of water flow or motor current of the boiler circulation pumps before the burners of the boiler can operate is recommended to ensure long service life The use of a mixing header fitted between t...

Page 21: ...r 20K 25K 35K T T T T T T 4 5 2 Water Pressure Loss The boiler pump must have a delivery head which can ensure the water flow rate in the following diagrams Water pressure loss graphs Data table 500 380 5 30 50 10 100 150 15 180 300 20 300 510 25 460 800 30 680 1120 35 900 0 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300 1400 5 10 15 20 25 30 Flow rate m3 h Pressure loss mbar 25K 20K 35K ...

Page 22: ... N N Q2 HC1 Pump QAC34 P N 5104726 L N B9 Outside sensor Main Power supply L E N Switched Supply for Clipins B3 DHW Tank Sensor QAA55 75 Room Unit G CL CL Q14 System Pump Y1 Y2 T B1 Y1 Y2 Mixer Valve Actuator H2 M BX21 BX22 U M Module No 2 L N QX23 QX22 QX21 N N B1 Flow temperature Sensor QAD 36 P N 5103867 230V 1A max Close Open RC1 QAA55 RC1 QAA75 Room Controller Room Controller P N 5138511 P N ...

Page 23: ...Sirius FS 21 GB IE 4 6 1 3 BASIC HEATING CIRCUIT HC1 HC2 DHW 4 6 1 4 BASIC HEATING CIRCUITS HC1 HC2 DHW SOLAR ...

Page 24: ... H2 M BX21 BX22 U M Module No 1 2 L N QX23 QX22 QX21 N N Q2 HC1 Pump Q6 HC2 Pump HC2 Thermostat P N 5117503 QAC34 P N 5104726 L N B9 Outside sensor Main Power supply L E N Switched Supply for Clipins B3 DHW Tank Sensor QAA55 75 Room Unit G CL CL B1 Flow temperature Sensor QAD 36 P N 5103867 HC1 QAA55 HC1 QAA75 Room Controller Room Controlle P N 5138511 P N 5117802 Mixer Valve Actuator 230V 1A max ...

Page 25: ...pproximately 4 5 It is advised that the 1 BSP threaded outlets provided on the boiler flow pipe are used for the fitting of the safety valve 5 2 CONDENSE CONNECTIONS Condensation is formed in the normal operation of the boiler and this must be continuously discharged into a drain Given the acidity level of condense discharge pH 3 5 4 5 only plastic material can be used for the discharge pipe work ...

Page 26: ... EARTHED Isolate the mains electrical supply before starting any work and observe relevant safety precautions 5 3 1 Access to electrical wiring panel 1 1 Undo 1 4 turn fasteners and lift panel vertically upwards 2 Undo single screw and lift panel vertically upwards 2 ...

Page 27: ...AGU2 5 Expansion Module supplied Low voltage channel 5 3 3 BMS Control Use of H2 Expansion modules 1 3 Remote enable The operating mode of the heating circuits or DHW when defined in the configuration lines 6046 6054 or 6062 can be turned on or off remotely using switched contacts between the H2 terminals Opening the contacts will switch the defined circuit s off Closing the circuit will bring it ...

Page 28: ...built in frost protection program will activate when the temperature detected inside the boiler drops below 5O C This results in the boiler switching on its burners until the water temperature inside the boiler reaches 16O C at which point the burners switch off and the boiler returns to standby mode again The circulation pump MUST operate during this process Failure to provide adequate water circ...

Page 29: ...tion 7 2 for details Using a small flatblade screwdriver set the pointer of the pot to the required delay in minutes 0 10 minutes range Flame on When no heat engines are in operation the circuit is open When the boiler burners are in operation a relay on the interface PCB will activate and close the circuit LPB OZW Communication Two wires provide communications with an external Siemens cascade con...

Page 30: ...ability Change parameters and view fault messages through PC and Smartphone Plant visualisation in the web browser or customised plant web pages Send fault messages to maximum of 4 e mail recipients Create custom system monitoring logs over hours days or weeks and send them automati cally to 2 e mail recipients every day week or month 2 digital inputs for reporting plant room failures or limitatio...

Page 31: ...r refrigeration sources about 1 5 metres above the floor The base provides the power for QAA55 and QAA75 When the units are removed from their base power is cut off i e the units are out of operation Connections 5 4 INSTALLING ROOM AND OUTSIDE TEMPERATURE SENSORS 5 4 1 Locating Room Thermostat Units all types Siemens QAA55 58 Siemens QAA75 78 Terminal Designation QAA55 QAA75 1 2 3 CL CL G BSB data...

Page 32: ...perature measurements and individually setting of heating circuit 2 However operating the occupancy button of unit 1 will activate all heat circuits Example settings QAA75 unit 1 QAA75 unit 2 Operating line 40 Room unit 1 Room unit 1 Operating line 42 Heating circuits 1 and 2 Heating circuit 2 Operating line 44 Independently Independently Operating line 46 Independently Independently Operating lin...

Page 33: ...Function Used as 40 Direct adjustment ru 1 ru 2 ru 3 P1 1 The room unit is addressed as RU1 default setting The room unit is addressed as RU2 The room unit is addressed as RU3 Automatic storage default setting A set point readjustment with the knob is adopted either by pressing the operating mode button or without any further confirmation time out Parameter Display Function Operation lock P1 2 P2 ...

Page 34: ...lation should be chosen so that the sensor can capture the room temperature as accurately as possible without getting adversely affected by direct solar radiation or other heat or refrigeration sources about 1 5 metres above the floor See section 5 4 1 for illustration Using the Left hand HMI of the appliance enter Commissioning mode see section on user levels and select Configuration menu Here ar...

Page 35: ...t to windows or openings on pitched and flat roofs Below windows or opening on pitched roofs 300 300 600 600 300 1000 600 2000 5 5 2 B23 Flue System This is an open flued arrangement where the air for combustion is drawn from the room and because of this the room must be ventilated If the boiler is installed in a compartment then it will require both a high level and a low level vent The flue prod...

Page 36: ...follows A compartment containing an open flued appliance shall be labelled as follows IMPORTANT Do not block the vents Do not use the compartment for storage 5 5 4 B23 Flue Ventilation Seasonal Adjustments Where a boiler is to operate in summer months the above allowance should be sufficient provided it does not operate for more than 50 of the time If the boiler is to be operated at 75 then an add...

Page 37: ... additional air inlet may be needed from outside to counter the effect of any such fans 5 5 6 Maximum Flue Lengths The overall resistance of the combined flue pipe work and flue terminal must not exceed a pressure drop of Each flue accessory such as bends and straight lengths restrict the flue system and decrease the boilers output To ensure that the output of the boiler matches the approved ratin...

Page 38: ...ow 3 10 1 30 3 90º Elbow 1 17 6 17 6 1m Straight lengths 2 5 0 10 0 Flexible flue liner m 8 13 9 110 8 Flue Terminal H D 1 0 Zeta 1 0 1 50 4 50 4 Total Flue Resistance Pa 264 4 180mm Flue outlet size Flue diameter 180mm Flue diameter 200mm Straight 1m 3 0 1 8 T piece boiler outlet 25 5 16 7 90º elbow 9 9 6 5 45º elbow 5 7 3 7 Flue terminal Zeta 0 05 conical 1 4 0 9 Flue terminal H D 1 0 Zeta 1 0 2...

Page 39: ...lation see section 2 3 for guidance It is recommended that the gas supply pipe work is fitted with a suitable union so that the boiler can be safely removed for major service or repair The gas meter regulator and supply pipe work must be sized so as to provide an adequate supply to the boiler in addition to any other appliances connected to the supply See section 3 2 for G20 gas consumption rates ...

Page 40: ...ur supplying electricity to the boiler Open the front facia flap and turn on the boiler The display should then proceed with system start up checks which may take several minutes When the boiler has finished these checks it should be displaying the default screen Cascade flow temperature on the left hand side HMI display screen The right hand HMI display screen should be displaying Boiler temperat...

Page 41: ...to controller stop mode refer to section 6 3 Operate at 0 load Remove safety cap from adjustment screw 5 for low load Set CO2 content on the adjustment screw 5 for low load according to the performance data section 3 2 with a TX40 Torx key Ensure CO levels do not exceed 150 ppm Clockwise CO2 content is increased anti clockwise CO2 content is decreased Replace safety cap on the adjusting screw 2 No...

Page 42: ...be adjusted in accordance with the Wobbe Index at any given time refer to gas supply company The CO2 content can be decided as follows CO2 content 9 3 WoN Wocurrent 0 5 6 4 DECOMMISSIONING DISPOSAL AND RECYCLING Only qualified competent persons should decommission and dismantle the appliance Before dismantling and removing please ensure you safely remove the power supply and isolated the appliance...

Page 43: ... the heating demand and forces the individual burner to operate manually The level of modulation can be controlled by pressing the information button and selecting a modulation level Push function A long press 3 seconds enables the DHW Push function This will give sole priority to the heating of DHW and cannot be cancelled once activated Once DHW has reached set temperature the controls return to ...

Page 44: ...ion has been manually activated Error message If this symbol appears for more than 30 seconds an error in the appliance has occurred Heating temporarily switched off ECO func tion active Info level activated Programming activated Timed heating programme Permanent Comfort temperature Permanent Reduced temperature Standby by with Frost protection Hot water on off Frost protection mode Hot water sele...

Page 45: ...Sirius FS 43 GB IE 6 5 3 Setting the Time and Date ...

Page 46: ...scroll wheel 7 Press OK 8 Rotate scroll wheel and select 1st phase off Press OK to change 1st time off with scroll wheel 9 Press OK button 10 Repeat steps 6 9 for up to 3 periods of on and off times 6 5 5 Setting the Hot Water Temperature The DHW set point can be altered by performing the following actions from the default screen 1 Press the OK button 2 Using the scroll wheel select Domestic Hot W...

Page 47: ...o button for more than 3 seconds Select Engineer from the list using the Wheel then press OK Use the Wheel to scroll down to Fault and press OK Step through the lines 6800 to 6995 to list the last 20 faults The first screen gives the general fault and the time and date of its occurrence Example screen Prog No 6800 09 32 26 01 2012 Fault History 1 133 Safety Time Exceeded Page two of fault history ...

Page 48: ...tion and adjustment of the temperature thermostats and radiators for the economic use of the system Remind the user that in order to comply to the regulations in force the boiler has to be inspected and serviced regularly as indicated by the manufacturer Explain the frost protection systems for this appliance If the internal water temperature of the appliance falls below 8o C the system pumps will...

Page 49: ...he integrity of flue seals Check condensate syphon and pipe work for leaks Check the combustion CO CO2 and gas running pressure Clean out filter strainer in return system Check the water inside the boiler is free of air and the automatic air vent operation Follow the procedures given in section 7 3 for full details on inspection and parts re moval Once maintenance has been completed it is recommen...

Page 50: ...radation Gaskets Inspect the condition of the door rope gasket silicone lip gasket and the gasket connecting the air flap to the burner door Replace if the rope gasket if it is damaged Replace the gaskets if they appear worn brittle or damaged Ignition and ionisation electrodes clean all electrodes with a fine wire brush and check the ceramic insulation is free from cracks or damage Check the igni...

Page 51: ... build up of dust particles Be careful when cleaning the fan to avoid force which may cause the fan to become unbalanced It is recommended that the following actions should be carried out after the above checks have been completed the boiler has been re assembled and reconnected to the electrical and gas supply Flue gas piping Inspect flue piping for gas tightness damage correct support and traces...

Page 52: ...ers and lift panel vertically upwards 2 Remove the locking screw and slide rail backwards 15mm then lift rail vertically upwards 3 Undo 1 4 turn fasteners and pull top of door outwards and lift door upwards 4 Remove 4 screws from the top and 2 screws from the bottom of panel and pull outwards 5 Remove 2 screws on front of panel and loosen 2 screws at rear of panel and pull forwards 1 2 3 4 Locking...

Page 53: ...to Flow sensor water pressure transmitter flow over heat cutoff device 7 Remove six screws to reveal access to Return sensor Cascade sensor condense blocked flue pressure switch condense pipe work upstanding pipe work couplers 8 Remove four screws to reveal access to Flue sample point rear overheat protection fuse 9 Remove four screws to reveal access to Rear overheat protection fuse 10 Remove two...

Page 54: ... control PCB LMS14 7 3 3 LPB communications bus 7 3 4 LMS14 Interface PCB 7 3 5 Relays 7 3 6 Flow and return temperature sensors 7 3 7 Water pressure transmitter 7 3 8 Flow high temperature limit thermostat 7 3 9 Rear High temperature thermal fuse 7 3 10 High temperature door limit thermostat 7 3 11 Spark generator 7 3 12 Spark and ionisation electrodes 7 3 13 Combustion fan 7 3 14 Gas valve 7 3 1...

Page 55: ...s Disconnect the electrical connection Using a screwdriver unscrew all 4 screws securing the HMI to the panel Remove display Replacement is the reverse 7 3 2 Heat Engine Boiler Control PCB LMS14 See Section 7 2 items 3 5 for access to electrical components Carefully pull off all the connectors on the PCB Release all 7 PCB supports by pinching the end of each pilar with a pair of pliers and slowly ...

Page 56: ... Undo the one nut providing earthing to the PCB Earthing post PCB Supports Fault delay adjustment Release the 3 PCB supports by pinching the end of each pillar with a pair of pliers and slowly withdraw the PCB from the supports Replacement is the reverse Set fault delay using the adjustable pot 0 10 minutes 7 3 5 Control Relays See Section 7 2 items 3 5 for access to electrical components Remove t...

Page 57: ...nscrew pressure switch from heat exchanger Replacement is the reverse When replacing any item screwed directly into the heat exchanger there will always be a quantity of water which will escape from the opening In order to minimise water loss place a small container directly below the item being changed and perform the exchange as quickly as possible 7 3 8 Flow High Temperature Limit Thermostat Se...

Page 58: ...the boiler after replacement of this thermostat inspect the insulation attached to the inside of the heat exchanger door to ensure that it is complete and undamaged Failure to do so could result in permanent damage 7 3 11 Spark Generator See section 7 2 item 3 for access Remove the front access door using a flat bladed screwdriver to release the catches at the top of the door Lift the top of the d...

Page 59: ...asket recommended 7 3 13 Combustion Fan See section 7 2 items 1 2 3 4 for access Remove the front access door using a flat bladed screwdriver to release the catches at the top of the door Lift the top of the door outwards and then upwards to remove it Unplug the two electrical connectors from the rear of the fan Remove the six bolts connecting the fan to the venturi Remove the four bolts connectin...

Page 60: ... bolts connecting the valve to the venturi top of valve and the 4 bolts connecting the gas valve to the gas pipe bottom of valve Carefully slide out valve Replacement is the reverse Refit with new O rings Recommission gas burner see section 6 4 7 3 15 Air Control Valve Remove fan see section 7 3 13 Disconnect the six way electrical connection underneath the air control valve Unscrew the five screw...

Page 61: ...inspection see section 7 3 17 If necessary replace burner tube by removing the air control valve see section 7 3 14 and pulling out the old tube Inspect condition of rubber seal and replace if worn or damaged Ensure that the seal is correctly located with its tab in alignment inside the aluminium cut out on the door Re assembly is the reverse 7 3 17 Burner Head Removal with Air Control Valve remov...

Page 62: ...deposits apply white vinegar to the coils using a hand sprayer and leave for 3 minutes Remove deposits using a nylon brush and rinse with plenty of clean water repeat if necessary Inspect condition of door seals and replace if there is any sign of wear or damage Do not use chemical treatments to clean out deposits from the heat exchanger Use only clean water or white vinegar as instructed above Wh...

Page 63: ...42139 23 LMS14 PCB 1 2 FS400 5142140 24 LMS14 PCB 1 2 FS525 5142141 25 LMS14 Interface PCB 5142142 26 PCB1 Multi connection cable HMI AGU2 5 5142143 27 PCB2 Connection cable 5142144 28 OCI345 Communication device c w cable 5142145 29 Power switch 5142146 30 Reset switch 5142147 31 Spark electrode lead 5142148 32 Spark electrode c w gasket screws 5142149 33 Spark generator 5142150 34 Water pressure...

Page 64: ...Sirius FS 62 GB IE 7 5 COMPONENT ILLUSTRATIONS 25 2 37 36 35 23 24 23 24 38 39 28 28 33 33 38 39 44 42 43 ...

Page 65: ...Sirius FS 63 GB IE 7 5 COMPONENT ILLUSTRATIONS CONTINUED 11 10 19 17 17 16 34 17 12 19 ...

Page 66: ...Sirius FS 64 GB IE 7 5 COMPONENT ILLUSTRATIONS CONTINUED 30 29 8 13 18 5 1 3 4 32 21 15 14 7 9 20 6 ...

Page 67: ...nded that spares are carried for these components 13 Combustion fan 18 Gas valve 23 LMS14 Control PCB 1 2 FS400 24 LMS14 Control PCB 1 2 FS525 32 Spark electrode c w gasket and screws 21 Ionisation electrode c w gasket and screws 44 AGU2 5 Clip in Extension 7 6 2 First Aid Kit A First Aid Kit has been designed to include a selection of the major spare parts for each model These items are available...

Page 68: ... 5142134 18 Gas valve c w seals 5142135 19 Heat exchanger rear overheat protection fuse 318O C 5142136 20 HMI display screen 5142137 21 Ionisation electrode c w gasket screws 5142138 23 LMS14 PCB 1 2 FS400 Kit only 5142140 24 LMS14 PCB 1 2 FS525 Kit only 5142141 25 LMS14 Interface PCB 5142142 28 OCI345 Communication device c w cable 5142145 31 Spark electrode lead 5142148 32 Spark electrode c w ga...

Page 69: ...Sirius FS 67 GB IE 7 6 3 First Aid Kit Parts List continued 13 1 5 31 25 33 28 20 43 42 10 18 24 23 44 15 ...

Page 70: ...SLT Lockout Overheat protection has been activated Allow appliance to cool down before resetting If problem persists establish causes of over heating before resetting appliance or replacing thermal fuses and rectify overheat devices Also check connector X18a and all flow return sensors 111 Shutdown limit thermostat Heat exchanger temperatures have been exceeded Investigate flow speeds and controls...

Page 71: ...age or restriction and pressure switch operation Check pressure switch value is 100 Pa above the maximum pressure generated inside the flue system when the boiler is operating from cold 166 Air Pressure Switch Air control valve operation closing has not been detected by the control system after the fan has switched off Check the operation of the air control valve position sensor relays and check t...

Page 72: ...easy integration with new or existing heating systems Technical Specification Works every time Features Benefits Lightweight aluminium heat exchanger For reliable highly efficient heat transfer Top hydraulic and flue connections Easier to connect and less space needed for working access Compact dimensions and small footprint Requires less space for installation Built in boiler control User friendl...