Morco II Series Technical Instructions
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Morco II Series Technical Instructions

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BOILER OUTPUT
BOILER OUTPUT
To Domestic Hot Water:
GB24/30 Minimum 8.0 kW (27,296 Btu/h)
GB24 Maximum 24.2 kW (82,570 Btu/h)
GB30 Maximum 30.3 kW (103,384 Btu/h)
UIN 212458 A08
July 2018
GB24 & GB30
Series II
Technical Instructions
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Morco House, Riverview Road, Beverley, East Yorkshire, HU17 0LD
Morco Products Ltd
Tel: 01482 325456
Website:
www.morcoproducts.co.uk
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GB24
Series II
To Central Heating:
GB24/30 Minimum 8.0 kW (27,296 Btu/h)
GB24/30 Maximum 24.2 kW (82,570 Btu/h)
Fax: 01482 212869

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Summary of Contents for Morco II Series

  • Page 1 GB24/30 Minimum 8.0 kW (27,296 Btu/h) GB24 Maximum 24.2 kW (82,570 Btu/h) GB24/30 Maximum 24.2 kW (82,570 Btu/h) GB30 Maximum 30.3 kW (103,384 Btu/h) Morco House, Riverview Road, Beverley, East Yorkshire, HU17 0LD Morco Products Ltd Tel: 01482 325456 Fax: 01482 212869 Website: www.morcoproducts.co.uk...
  • Page 2 Morco GB24 & GB30 Series II Destination Country: BE = Belgium Combination Boiler CH = Switzerland CZ = Czech Republic DE = Germany ES = Spain FR = France GB = UK GR = Greece IE = Ireland IT = Italy...

  • Page 3: Table Of Contents

    Introduction ..............................5 Boiler Dimensions, Services & Clearances....................7 Boiler Assembly .............................8 INSTALLATION .............................9 Fluing ................................9 Condensate Drain ............................14 Wiring ................................16 SERVICING ..............................17 FAULT FINDING ............................34 Operating Modes ............................34 Fault Codes..............................35 Fault Finding Charts............................36 Morco reserve the right to vary specification without notice...

  • Page 4: General

    SECTION 1 - GENERAL Table 1 - General Data Morco GB Series II Gas Supply - G31 - 37mbar (I - G31 - 30mbar DE) 2H3P Gas Supply Connection 15mm copper compression Injector Size 3.75 3.75 Inlet Connection Domestic Hot Water G ½...

  • Page 5: Introduction

    1.1 INTRODUCTION This boiler may require 2 or more operatives to move it to its The Morco GB Series II range of boilers are wall mounted, full installation site, remove it from its packaging base and during sequence, automatic spark ignition, low water content, fanned movement into its installation location.
  • Page 6 Servicing Instructions or as otherwise recommended by Morco in writing. If in doubt please enquire. Any direct connection of a control device not approved by Morco could invalidate the certification and the normal appliance warranty. It could also infringe the Gas Safety Regulations and the above regulations.

  • Page 7: Boiler Dimensions, Services & Clearances

    SECTION 1 - GENERAL 1.2 BOILER DIMENSIONS, SERVICES & CLEARANCES all dimensions in mm The boiler connections are made on the boiler bulkhead fittings. (24”). Where the space into which the boiler is going to be installed is less than the length of flue required the flue must The following minimum clearances must be maintained for be fitted from the outside.

  • Page 8: Boiler Assembly

    SECTION 1 - GENERAL 1.3 BOILER ASSEMBLY - Exploded View Note that item numbers are linked to the spares list PRESSURE GAUGE ASSY GAS COCK ELECTRODE DETECTION PUMP HEAD PIPE - GAS INLET IGNITER UNIT AIR VENT PUMP GAS VALVE FLOW THERMISTOR DIVERTOR VALVE MOTOR PIPE - GAS INJECTOR...

  • Page 9: Installation

    SECTION 2 - INSTALLATION 2.1 DETERMINING THE FLUE LENGTH IMPORTANT. The boiler must be installed in a vertical position in accordance to the installation instructions. STANDARD FLUE KITS Horizontal Flue Terminal RSF303 (600mm long) - contains: Flue turret, non telescopic single piece flue incorporating a terminal and inner rubber wall seal.
  • Page 10 SECTION 2 - INSTALLATION 2.2 DETERMINING THE FLUE LENGTH FIGURE 1 REAR FLUE SIDE FLUE Cut flue length = distance from edge of turret to outside of Cut flue length = distance from edge of turret to outside of wall dimension A + 47mm. wall dimension B + 47mm.
  • Page 11 SECTION 2 - INSTALLATION 2.4 INSTALLING THE FLUE FITTING FLUE THROUGH THE WALL 1. Ensure the seam and the outlet terminal are at the top and fitted as shown. 2. Once the flue is installed it is IMPORTANT that the white air duct protrudes from the aluminium flue collar (RSF 060) at least 17mm.
  • Page 12 SECTION 2 - INSTALLATION 2.5 FLUE EXTENSIONS RSF341 (OPTIONAL) For side outlet refer to section 1.2 before commencing any work. INNER PIPE ASSEMBLY INSTRUCTIONS 1. Make sure that ‘top hat’ on the collar (A) fits over the 3. Slide the pipe and collar assembly back into the outer rectangular form on the inner plastic pipe (B).
  • Page 13 SECTION 2 - INSTALLATION 2.8 FITTING THE OPTIONAL ROOF FLUE KIT RSF345 (OPTIONAL) - Flat or Pitched- Note. A 5º or 14º pitched roof plate (not supplied) is required before proceeding with the installation of this kit. This kit is suitable for both 5º and 14º pitched roof terminations, using a concentric flue to run vertically from the top of the boiler and terminating above roof level.

  • Page 14: Condensate Drain

    SECTION 2 - INSTALLATION 2.10 CONDENSATE DRAIN Internal Drain Connections Wherever possible, the condensate drainage pipe should be routed to drain by gravity to a suitable internal foul water discharge point such as an internal soil and vent stack or kitchen or bathroom waste pipe etc.
  • Page 15 SECTION 2 - INSTALLATION CONDENSATE DRAIN - CONT’D..Figure 3 - Connection of a Condensate Pump Typical Figure 4 - Connection of Condensate Drainage Pipe to Method (see manufacturers detailed instructions) External Soil & Vent Stack Boiler Water/weather Visible air break with 75mm proof insulation Boiler...

  • Page 16: Wiring

    SECTION 2 - INSTALLATION 2.11 WIRING DIAGRAM...

  • Page 17: Servicing

    0.004 AND the integrity of the complete flue system and combustion circuit seals have been verified and the inlet gas pressure have been verified, then contact Morco. Ensure all caps and seals are re-fitted after use...
  • Page 18 SECTION 3 - SERVICING 3.2 BOILER UPPER & LOWER FRONT PANEL REMOVAL / REPLACEMENT REMOVAL REPLACEMENT 1. Lift the lower front panel access panel. 4. Hook the upper panel onto the top retaining clips. 2. Unscrew the two fixing screws, close the access panel to 5.
  • Page 19 SECTION 3 - SERVICING 3.4 BURNER REMOVAL AND CLEANING 1. Ensure the sump is fully drained 2. Undo the two screws and remove the sump cover retaining the lower flue manifold. 3. Lift the manifold to clear the bottom sealing gasket and remove manifold.
  • Page 20 SECTION 3 - SERVICING 3.6 CLEANING THE HEAT EXCHANGER Note: Ensure the condensate trap/siphon is fully drained before cleaning. Refer to Ignition Electrode Flame Detection Frame 3.17. 1. Remove ignition and flame detection electrodes. Refer to Frames 3.12 & 3.13. 2.
  • Page 21 SECTION 3 - SERVICING 3.8 REPLACEMENT OF COMPONENTS GENERAL IMPORTANT. Ensure all gas valve connections are gas tight with a gas When replacing ANY component soundness check up to the gas control valve. 1. Isolate the electricity supply. When work is complete, the front panels must be correctly refitted - ensuring that a good seal is made.
  • Page 22 SECTION 3 - SERVICING 3.10 BURNER INJECTOR REPLACEMENT 1. Refer to Frame 3.8. 2. Disconnect the electrical leads from the fan. 3. Remove the clip from the gas valve to venturi pipe and ease the pipe upwards, rotate and ease down to remove. 4.
  • Page 23 SECTION 3 - SERVICING 3.12 IGNITION ELECTRODE REPLACEMENT 1. Refer to Frame 3.8. 2. Remove the burner. Refer to Frame 3.10. 3. Unplug the ignition lead from the electrode. Ignition Electrode 4. Remove the earth lead from the ignition electrode. 5.
  • Page 24 SECTION 3 - SERVICING 3.14 SPARK GENERATOR REPLACEMENT 1. Refer to Frame 3.8. 2. Disconnect the leads from the spark generator. 3. Pull the spark generator to unclip Spark Generator from the mounting bracket. 4. Fit the new spark generator and re- assemble in reverse order ensuring that the the earth lead is replaced.
  • Page 25 SECTION 3 - SERVICING 3.16 DIVERTER VALVE ACTUATOR REPLACEMENT To remove the motor: 1. Refer to Frame 3.8. 2. Remove the condensate trap/siphon. Refer to Frame 3.17. 3. Disconnect the inline connector block. 4. Place a flat bladed screwdriver in the actuator slot provided and ease out the actuator.
  • Page 26 SECTION 3 - SERVICING 3.18 MAIN PCB REPLACEMENT * Note. that production boiler PCB’s are factory pre-set to operate for boiler range and output, but when ordering Primary PCB as a spare, an additional Boiler Chip Card (BCC) MUST also be purchased for your specific boiler range and output.
  • Page 27 SECTION 3 - SERVICING 3.19 USER CONTROL PCB REPLACEMENT Note. Fit the earth strap provided with the PCB to your wrist and a suitable earth on the boiler chassis. 1. Refer to Frame 3.8. 2. Remove the main PCB, refer to Frame 3.18. 3.
  • Page 28 SECTION 3 - SERVICING 3.21 DRAINING THE BOILER CENTRAL HEATING CIRCUIT 1. Refer to Frame 3.8. 2. Close all the CH water isolating valves on the boiler inlet. 3. To drain the primary heat exchanger circuit: Open the drain valve and attach a length of hose to the CH drain point. 4.
  • Page 29 SECTION 3 - SERVICING 3.24 SAFETY RELIEF VALVE RENEWAL 1. Refer to Frame 3.8. 2. Drain the boiler. Refer to Frame 3.21. 3. Remove the return thermistor. Refer to frame 3.32. 4. Pull out and remove the clip (positioned behind the safety valve) retaining the safety valve.
  • Page 30 SECTION 3 - SERVICING 3.26 DIVERTER VALVE BODY ASSEMBLY REPLACEMENT To remove the valve body assembly: 16. Twist and remove the DHW manifold. 1. Refer to Frame 3.8. 17. Remove the two diverter valve body fixing screws and withdraw the diverter valve body assembly. 2.
  • Page 31 SECTION 3 - SERVICING 3.29 CH WATER PRESSURE SWITCH REPLACEMENT 1. Refer to Frame 3.8. 2. Drain the boiler. Refer to Frame 3.21. 3. Pull off the two electrical connections. 4. Using a suitable tool, pull out the metal retaining clip. 5.
  • Page 32 SECTION 3 - SERVICING 3.32 RETURN THERMISTOR REPLACEMENT 1. Refer to Frame 3.8. 2. Drain the boiler. Refer to Frame 3.21. 3. Unplug the electrical connection. 4. Using a suitable tool, pull out the retaining clip. 5. Carefully pull the thermistor upwards to remove. 6.
  • Page 33 SECTION 3 - SERVICING 3.34 EXPANSION VESSEL RECHARGING & REPLACEMENT RECHARGING 1. Refer to Frame 3.8. Recharge Point 2. Remove the charge point cover. 3. Recharge the tank pressure to 0.75 bar. 4. Re-assemble in reverse order 5. Check operation of the boiler. Refer to Frames 28 &...

  • Page 34: Fault Finding

    SECTION 4 - FAULT FINDING 4.1 OPERATION MODES DESCRIPTION DISPLAY CODE ON BOILER The boiler is in standby mode awaiting either a central heating call or hot water demand. The boiler has a call for central heating but the appliance has reached the desired temperature set on the boiler.

  • Page 35: Fault Codes

    Check system water pressure is between 1 & 1.5bar on the system pressure gauge (G). To re- pressurise the system see Section 3. If the boiler still fails to operate then please contact Morco (if under warranty) or alternatively a Gas Safe Registered Engineer if outside of the warranty period.

  • Page 36: Fault Finding Charts

    SECTION 4 - FAULT FINDING 4.3 ALTERNATING ‘L’ AND ‘1’ - FLOW TEMPERATURE OVERHEAT LOCKOUT Is the Boiler and CH System filled with water and all Fill and vent the system and open all isolation and radiator valves open? isolation valves, then reset boiler Is the Flow/Return Differential across the Boiler in Check that the Pump is rotating freely.
  • Page 37 SECTION 4 - FAULT FINDING 4.5 ALTERNATING ‘L’ AND ‘5’ - 5 RESETS WITHIN 15 MINS Turn power off and on 4.6 ALTERNATING ‘L’ AND ‘6’ - FALSE FLAME LOCKOUT Check routing and integrity of internal boiler Reset the boiler, does Boiler Work OK? wiring is OK.
  • Page 38 SECTION 4 - FAULT FINDING 4.8 ALTERNATING ‘F’ AND ‘2’ - FLAME LOSS Is the Gas Pressure available at Does the boiler ignite for a short Check gas supply and the Boiler Inlet (>34.5 mbar or >28 time and then extinguish? rectify fault mbar in DE)? Check the detection electrode and...
  • Page 39 SECTION 4 - FAULT FINDING 4.10 ALTERNATING ‘F’ AND ‘4’ - FLOW THERMISTOR FAULT Check the resistance using a suitable multimeter Fit a new Thermistor connected across the thermistor’s terminal pins. At 25 expect 9,700 - 10,300 Ohms At 60 expect 2,400 - 2,600 Ohms...
  • Page 40 SECTION 4 - FAULT FINDING 4.12 ALTERNATING ‘F’ AND ‘7’ - LOW MAINS VOLTAGE Reset the boiler Has the boiler reset? Contact electricity provider RESET PROCEDURE - To reset boiler, turn mode knob to reset position and immediately turn knob back to required setting. 4.13 ALTERNATING ‘F’...
  • Page 41 SECTION 4 - FAULT FINDING 4.16 NO CH OPERATION BUT HW WORKS OK Move the mode knob to the Winter position Is the mode knob in the Winter position? Are the Timer and the Room Thermostat switched Switch the Timer and Room Thermostat On Open the Radiator Valves Are the Radiator Valves Open? There is no Voltage from the Timer/Room Stat.
  • Page 42 SECTION 4 - FAULT FINDING 4.17 NO HW BUT CH ON Is hot and cold pipework crossed? Does the display show “d” when a tap is on? Adjust flow rates to achieve 35º Are the flow rates correct?. temp rise and check filter fitted in turbine is not blocked with debris.
  • Page 43 NOTES...
  • Page 44 For more detailed servicing information, workshop manuals, technical advice, spare parts, product training, please phone us on 01482 325456 or contact us at the address below: MORCO PRODUCTS LTD Morco House, Riverview Road, Beverley, East Yorkshire HU17 0LD TEL: 01482 325456 FAX: 01482 212869 EMAIL: sales@morcoproducts.co.uk WEBSITE: www.morcoproducts.co.uk...

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Gb24Gb30Gb24 seriesGb30 series

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