Advertisement

MH 3M & MH 4M
SERVICE MANUAL
SM_MH 3M_4M Ver.1.2_May 2016

Advertisement

Table of Contents
loading
Need help?

Need help?

Do you have a question about the MH 3M and is the answer not in the manual?

Questions and answers

Subscribe to Our Youtube Channel

Summary of Contents for Nilfisk-Advance MH 3M

  • Page 1 MH 3M & MH 4M SERVICE MANUAL SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 2 Preface This service manual contains detailed description of the main repair work on the hot HPW MH 3M & 4M. Repair work requires a suitable testing workplace with the necessary water and power supply. If operating errors are evident, refer the customer to the operating instructions.
  • Page 3: Table Of Contents

    Safety instructions Technical data 5-24 Construction 25-40 Function 41-56 Troubleshooting 57-59 Service / Repair 60-81 Adjustment / Test 82-90 Wiring diagrams 91-98 I. Special tools...
  • Page 4: Safety Instructions

    Safety instructions For your own safety Observe valid safety regulations for electrical equipment. In particular, observe the following regulations: IEC 60335-2-79 EN 60335-2-79 Additionally: Repair work should be carried Also see national regulations out by persons instructed in electrical installations or by trained electricians only.
  • Page 5: Technical Data

    Technical data SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 6 Technical data SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 7 Technical data SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 8 Technical data SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 9 Technical data SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 10 Technical data SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 11 Technical data SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 12 Technical data SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 13 Technical data SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 14 Technical data SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 15 Technical data SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 16 Technical data SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 17 Technical data SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 18 Technical data SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 19 Technical data SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 20 Technical data SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 21 Technical data SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 22 Technical data SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 23 Technical data SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 24 Technical data SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 25: Construction

    Construction MH 3M MH 3M variats: MH 3M -140/580 PA ”EU”, 230/1/50/16 MH 3M -100/600 PA ”EU”, 230/1/50/13 MH 3M -160/770 PA ”EU”, 400/3/50/8 Operating panel Lance holder Water outlet Hook f. HP hose Water inlet Lock f. service door Holders f.
  • Page 26 Construction MH 3M AntiStone adjustment AntiStone valve Exhaust temp. Reset Lid for adding Anti-freeze Lid for Water Break Tank Outlet HP hose Fan housing Flow switch Ignition electrodes Safety valve Flame sensor Chimney Exhaust temp. sensor Boiler Lock f. service door...
  • Page 27 Construction MH 4M FA AntiStone adjustment AntiStone valve Exhaust temp. Reset Lid for adding Anti-freeze Lid for Water Break Tank Outlet HP hose Fan housing Double Flow switch Ignition electrodes Double non-return valve Flame sensor Chimney Exhaust temp. sensor Boiler Lock f.
  • Page 28 Construction MH 4M PA AntiStone adjustment AntiStone valve Exhaust temp. Reset Lid for adding Anti-freeze Lid for Water Break Tank Outlet HP hose Fan housing Flow switch Ignition electrodes Safety Valve Flame sensor Chimney Exhaust temp. sensor Boiler Lock f. service door Oil container Micro switch box High Pressure Outlet Pipe...
  • Page 29 Construction MH 3M Detergent dosing valve Operating panel MH 3M Cold water mode Thermostat ECO—mode: EcoMode for low con‐ ON/OFF switch Hot water mode sump on hea ng stage at  60°C.  Boiler overheated Ecological mode Power ON AntiStone low No flame Service interval due/expired SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 30 Construction MH 4M Operating panel MH 4M Cold water mode Thermostat ECO—mode: EcoMode for low con‐ ON/OFF switch Hot water mode sump on hea ng stage at  60°C.  Pump oil level low Boiler overheated Ecological mode Power ON AntiStone low No flame Service interval Fuel tank level low due/expired SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 31 Construction MH 3M & MH 4M Board with LED’s Thermostat ON/OFF switch Detergent dosing valve AntiStone tank Contactor The control transformer is placed below the NEO main circuit board. Push on the 3 plastic clips on the side of the of the circuit board to remove it for ac- cess to control transformer.
  • Page 32 Construction MH 3M and MH 4M Boiler The boiler is the heat generating part of a hot water machine. It consists of a labyrinth-constructed tube coil, which encloses the combustion chamber. The tube coil is enclosed by a double container with boiler jacket, bottom, and top in a sandwich construction, between which the combustion air is routed into the combustion.
  • Page 33 Construction MH 3M & MH 4M Water Break Tank Before removing the lid, the wires clicked into the Water break tank holders on top of the lid must be removed. To remove the lid from the water break tank 4 clips must be opened.
  • Page 34 Construction MH 3 & MH 4 Chassis SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 35 Construction MH 3 & MH 4 Cabinet SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 36 Construction MH 3 & MH 4 Hose reel SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 37 Construction MH 3M PA Pump components Motor components SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 38 Construction MH 4M PA Motor-pump components Motor-pump components Unloader components SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 39 Construction MH 4M FA Motor-pump components Motor-pump components By-pass valve components SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 40 Construction MH 3M—MH 4M Flow switch Flow switch MH 4M FA. Flow switch MH 3M & 4M PA. Flow piston Flow piston Reed switch Reed switch Double non-return valve Safety valve Flow piston SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 41: Function

    Function MH 3M If the machine and the power supply are working correctly the following will happend during start up. Suction from pump Cold water mode ON/OFF switch Hot water mode Thermostat Detergent Detergent dosing valve Connected to water tank ECO—mode:...
  • Page 42 Function MH 3M If the machine and the power supply are working correctly the following will happend during start up. Suction from pump Cold water mode ON/OFF switch Hot water mode Thermostat Detergent Detergent dosing valve Connected to water tank ECO—mode:...
  • Page 43 Function MH 4M If the machine and the power supply are working correctly the following will happend during start up. Suction from pump Cold water mode Detergent A Detergent A ON/OFF Hot water mode Thermostat Manometer Detergent dosing valve switch Connected to water tank ECO—mode: EcoMode for low fuel con‐...
  • Page 44 Function MH 4M If the machine and the power supply are working correctly the following will happend during start up. Suction from pump Cold water mode Detergent A Detergent A ON/OFF Hot water mode Thermostat Manometer Detergent dosing valve switch Connected to water tank ECO—mode: EcoMode for low fuel con‐...
  • Page 45 Function MH 3M and MH 4M Boiler Air distributor Water outlet Exhaust temp. switch Chimney Fuel nozzle and electro- Water inlet Heating coil pipes Inner boiler jacket Outer boiler jacket The heat exchanger is the functional link between the heating subsystem and the water subsystem.
  • Page 46 Function MH 3M and MH 4M Boiler Air distributor Water outlet Exhaust temp. switch Chimney Fuel nozzle and electro- Water inlet Heating coil pipes Inner boiler jacket Outer boiler jacket At the same time fuel is drawn in from the fuel tank by the fuel pump through the fuel filters. The fuel is supplied by the fuel pump (when the solenoid valve is open) to the nozzle nozzle.
  • Page 47 Function Sensors: (Depending on model) A1: PCB Processor A2: PCB Display A3: PCB Temperature A4: PCB AntiStone B1: Temperature sensor in the outlet from the boiler. Controls the combustion (Y1 on/off) according to setting. B2: Flow switch senses the flow out of the pump into the boiler and controls solenoid Y1 on/off. B4: Micro switch signals to the control board if there is flow of water out of the pump or not.
  • Page 48 Function MH 3M Schematic drawing 1 ~ The schematic drawing of the pump head below is made to get a better understanding of the function. NOTE ! In the schematic drawing of the pump head is shown a two-way easy start valve, which is the layout for all the single phase machines.
  • Page 49 Function MH 3M Schematic drawing 3 ~ The schematic drawing of the pump head below is made to get a better understanding of the function. NOTE ! In the schematic drawing of the pump head is shown a two-way easy start valve, which is the layout for all the single phase machines.
  • Page 50 Function MH 4M FA model, Function By-pass system Water runs under pressure from the pump through the injector nozzle, where there is a pressure drop made. Water also enters the chamber between the by-pass pistons. Due to a higher pressure between the pistons than under the lower piston, the by-pass valve is closed and the machine runs in working mode.
  • Page 51 Function MH 4M PA model, Function Unloader system Pressure Activated Unloader— working pressure (open spray handle Motor/pump Unloader—Open spray handle. Machine in stand-by with stand-by pressure. Motor/pump Unit. Mounted with a lance and high pressure nozzle Micro switch. the spray handle (8) is now activated. Activation arm.
  • Page 52 Function MH 4M PA model, Function Unloader system Pressure Activated Unloader— by pass (closed spray handle) Motor/pump Unloader—Closed spray handle. The machine is started with closed spray handle (8). The pressure rises until the cut-off pressure is reached. Motor/pump Unit. The unloader piston (5) is pressed forward caused by the Micro switch.
  • Page 53 Function MH 4M PA model, Function Unloader system Unloader in Stand-by (closed spray handle) and open water regulator Valve for water regulation is open. Approx. 50% of water volume is run- ning in by-pass (back to suction side in pump) Water can pass through the non-return valve Opening between pressure and suction side in pump, because unloader piston has lifted the ball from its seat.
  • Page 54 Function MH 4M PA model, Function Unloader system Unloader in working pressure position (open spray handle) and open water regulator Valve for water regulation is open. Approx. 50% of water volume is run- ning in by-pass (back to suction side in pump) Water can pass through the non-return valve Non-return valve is open and water can pass through and flow to the outlet of the machine...
  • Page 55 Function MH 4M PA model, Function Unloader system Unloader in working pressure position (Now CLOSING spray handle) with open water regulator Valve for water regulation is open. Non-return valve is closing for opening to the water regulation valve for building up the pressure with open water regulator. This is happeing when the spray handle is closing Unloader piston will lift the ball from its seat, when cut-off pressure has been reached.
  • Page 56 Function MH 4M PA model, Function Unloader system Damper valve The function of the PBV is to close the opening to the water regulator valve, so pressure can be builed up to the cut-off pressure (for stopping the pump). Now Damper valve is introduced. The function of the damper valve is to make sure the unloader stem move slower after opening the spray handle.
  • Page 57: Troubleshooting

    Troubleshooting MH 3M & MH 4M SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 58 Troubleshooting MH 3M & MH 4M SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 59 Troubleshooting MH 3M & MH 4M Nilfisk Service Tool can also be used for trouble shooting. For more information please read TSB-PPW-2016-006 Nilfisk Service Tool Instructions MH 3M_4M Nilfisk Service Tool must be used for re-setting the service light, and changing the service hours.
  • Page 60: Service / Repair

    Service / Repair MH 3M Pump Open service door by turning the two quarter turns Pump seen through service opening Remove the U-pin to dismount the water inlet con- Remove screw for micro switch bracket nection Remove the U-pin to dismount the micro switch Pull off the micro switch box from the unloader SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 61 Service / Repair MH 3M Pump Pull off the cylinder head Dismount the 3 cylinder head bolts Dismount the 4 bolts holding the cylinder block Dismount the cylinder block Dismount the bearing disc and bearing Pull off the wobble disc.
  • Page 62 Service / Repair MH 3M Wobble disc & Oil Seals Wobble disc, bearing and bearing track Pull out the 3 oil seals from the cylinder block. (Use e.g. a Disassemble the 3 spacers. Bahco Puller type 4521 N-F. Bahco puller (not shown) for puller is type 4524 G) Oil seals must be installed by using punch 1210996.
  • Page 63 Service / Repair MH 3M Cylinder head and water seals disassembling Trust colar and water seals pulled out with puller. Pull out the water seals and trust collars. (Use e.g. a Bahco Puller type 4521 N-F. Bahco puller (not shown) for puller is type 4524 G) Trust collar and water seals.
  • Page 64 Service / Repair MH 3M Non-return valve disassembling Disassemble the outlet coupling and fitting Non-return valve housing Spring and non-return piston can be pulled up with a pair of Non-return components. pliers. Regulator Safety Block disassembling Loosen and dismount fitting f/micro switch.
  • Page 65 Service / Repair MH 3M Unloader Unloader disassembling Loosen unbloader valve Pull out the unloader valve Counter nut Adjustment screw Housing Lock pin Lock ring for lock pin Washer f/spring Spring Valve cone housing Unloader components Valve cone O-ring SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 66 Service / Repair MH 3M PumpTorque Settings SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 67 Service / Repair MH 4M pump Dismount the outlet, automatic venting valve, ma- Use a small screwdriver for pulling out the pin for nometer and water inlet connections. the water inlet connection Pull out the water inelt connection from the water Remove the 3 screws for the by-pass valve inelt manifold Remove the 3 screws for the cylinder head...
  • Page 68 Service / Repair MH 4M pump Remove the 3 secondary water seals, if left on the pistons Pull out the cylinder head Remove the Cylinder block Remove the 2 screws (one in each side) for the Remove the bearing track and the roller bearing Remove the screw which holds the wobble disc.
  • Page 69 Service / Repair MH 4M pump Pull out the wobble disc using a 16 mm bolt. Remove the 3 secondary water seals Remember to remove the braing track sitting in the Remove the 3 thrust collars with an expandable Remove the 3 primary seasl with an expandable puller.
  • Page 70 Service / Repair MH 4M pump Trust collar, water seals, distance ring, suction val- ve and cylinder head Remove the 3 O-rings from the pressure vavles Remove the 3 pressure valves Remove the 3 pressure valves Pull up the 3 pressure valve seats. Use a 5mm Remove the 3 distance rings for the oil seals screw—there are thrads inside the pressure valve SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 71 Service / Repair MH 4M pump Pull out the oil seals from the cylinder block using an expandable puller. Mount the oil seals by using a 19 mm box spanner Replace the complete wobble dsic system and make sure the components are assemb- The curved edge (A) of the bearing tracks led as shown on the next 2 pictures must be mounted against the D-bearing...
  • Page 72 Service / Repair MH 4M pump Torque specificcations 55 Nm 20 Nm 10 Nm 40 Nm Bolt for wobble disc: 20 Nm SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 73 Service / Repair MH 4M pump 3-6: Automatic venting valve Injector nozzle for control piston Return valve for by-pass water By-pass valve housing Handle for water regulation Plug for by-pass valve Control piston Safety valve SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 74 Service / Repair MH 3 & MH 4 Hose reel Caryfully install the back-up ring (pos. 9) for the O- Do NOT open the back-up ringas shown above ring )pos. 10), by ”rolling” it onto the swivel Push in the back-up ring before sliding in the bea- Lubricate the svivel with silicone grease ring bushing (pos.
  • Page 75 Service / Repair Heating system. Support foot when removing boiler or rear wheels Support foot Support foot must be placed below the two fork lift symbols Machine supported by the support foot When the support foot is positioned, plase your foot on the support foot as show above, ,and pull the machine against you SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 76 Service / Repair Heating system. Dismount the water inlet and water outlet connecti- Boiler top view ons. Dismount the 2 screws and the cable tie for the exhaust temperature sensor, and pull out the sensor. Dismount the 2 screws for the flame sensor and the Dismount the fuel hose.
  • Page 77 Service / Repair Heating system. After the 4 nuts are dismounted the heatiing coil Dismount the 4 brass nuts and washers from the in- including the inner boiler top can be lifted up. ner top. It is recommended to replace the insulation when servicing the boiler.
  • Page 78 Service / Repair Heating system. If the exhaust temperature reaches 270°C (518°F) the The exhaust temperature sensor is fitted with 2 screws machine cuts out. The thermostat for the sensor is in the chimney. placed in the E-box, and can be reset by dismounting the cap, and push the button.
  • Page 79 Service / Repair Heating system. Check and clean fuel filter in fuel tank inlet. Replace fuel filter on fuel line. Pull off the fuel filter from the plug and replace. Dismount the plug below the fuel outlet port. Fuel pressure adjustment scsrew SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 80 Service / Repair Heating system. Fuel tank dismount Remove cabinet. Dismount the front bumper, by re- Remove bumper by pulling the bumper up (see red moving the 4 screws (See red arrows in picture arrows), and then pull bumper against you. above) Remove the right wheel, fuel tank lid, pump outlet Remove screw for support pipe...
  • Page 81 Service / Repair Heating system. Fuel tank dismount Lift the fuel tank a little bit, and then pull the tank out Water break tank lifted from its bracket as shown above. When the fuel tank is as far out as shown above, the fuel hoses (2), and the fuel level sensor (if installed) must be dismounted before re- moving the tank completely.
  • Page 82: Adjustment / Test

    Adjustment / Test Boiler Settings Introduction Every fuel-burning appliance such as pressure washers depends on a proper mix of fuel and air for proper combustion. Therefore some adjustment of the air supply to the burner may be necessary to take account of altitude and the resulting air pressure. This is true whether your fuel is Diesel or Ker- osene.
  • Page 83 Adjustment / Test Boiler Settings Manometer Max 20 bar for fuel pressure Connection for manometer Flue Gas Measurement Step no: Description Picture Mount the fuel pressure manometer on the fuel pump, or on the pipeline between fuel pump and fuel nozzle.
  • Page 84 Adjustment / Test Boiler Settings Set the oil pressure according to Technical Data in the service manual Start up the flue gas analyzer. Wait until the instru- ment is calibrated ( See flue gas analyzer manual) Place the flue gas probe in the centre of the chimney Set the air damper until specified CO is obtained.
  • Page 85 Adjustment / Test Boiler Settings Demount the fluegas analyser and measure the soot with soot pump or Testo 308 in the centre of the chimney. Soot test must be done according to the soot test equipment manual. ( For soot pump 10 strokes, slow- Soot <...
  • Page 86 Adjustment / Test MH 3M Unloader Adjustment of the retaining pressure Adjustment of retaining pressure Check of retaining pressure The retaining pressure is adjusted on the un- Install test pressure gauge 1206358 between loader machine outlet and the high pressure hose.
  • Page 87 Adjustment / Test MH 4M Unloader Unloader - Retaining pressure adjustment. Counter nut Adjusting nut Unloader spring Install the test manometer, 1206358, between the machine outlet and the high pressure hose. Run machine with full pressure and water volume (water regulator closed). Close the spray handle, let the motor stop and read the retaining pressure on the test manometer The retaining pressure is adjusted by tightning or loosening the unloader spring.
  • Page 88 Adjustment / Test MH 4M By-pass valve By-pass valve—opening pressure adjustment. Adjustment screw Counter nut Install the test manometer, 1206358, between the outlet of the machine and the high pressure hose. Start machine in cold water with full water volume (water regulator closed) with correct high pressure nozzle, and read the output pressure on the test manometer.
  • Page 89 Adjustment / Test MH 4M By-pass valve Water regulator adjustment With dismounted blue handle for the water regulator, and machine without pressure do the following to adjust the water regulator: Turn gently the small brass shaft (1) counterclockwise until it JUST touches the surface of the plug (2) Push down the blue handle (3)on the top of the shaft, and position it so the...
  • Page 90 Adjustment / Test MH 3M & 4M AntiStone valve Adjustment knob for AntiStone valve Adjustment knob for settings SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 91: Wiring Diagrams

    Wiring diagrams SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 92 Wiring diagrams SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 93 Wiring diagrams SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 94 Wiring diagrams SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 95 Wiring diagrams SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 96 Wiring diagrams SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 97 Wiring diagrams SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 98 Wiring diagrams Fuses How to trouble shoot a blow fuse. This is meant as a guideline for finding the component that is the root cause to a blown fuse. Fuses: Check the components in the order they are listed below. Fuse Components to check for root cause M2;...
  • Page 99: Special Tools

    Special Tools / Spare Parts Part Number Description Remarks Special Tools Adjustment unloader & By- 1206358 Test Pressure Gauge pass valve 17246 Fuel pressure gauge Measurering fuel pressure Connecting HP hose to Test 1220126 Male coupling Pressure Gauge 101221030 Nilfisk Service Tool Accessing NEO circuit board Supporting machine when re- 106403200...
  • Page 100 Notes SM_MH 3M_4M Ver.1.2_May 2016...
  • Page 101 Nilfisk A/S Industrivej 1 9650 Hadsund Denmark www.nilfisk.com...

Table of Contents

Save PDF