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Serial number ● Date purchased ● Installation location and type ● Error code, if any appears on the front panel display ● Version: 1.0(February, 2022) Navien LTD Building 2, Guildford Business Park, Guildford, GU2 8XH TEL 0844 332 2323 www.navien.co.uk...
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Manual These appliances are for use with natural gas or LPG. ● (An LPG conversion kit is included with the boiler.) Model GC Number NCB500-1.5S/37K Natural Gas NCB500-2S/41K NCB500-1.5S/37K NCB500-2S/41K Keep this manual near this boiler for future reference whenever maintenance or service is required.
1. Safety Information The following safety symbols are used in this manual. Read and DANGER follow all safety instructions in this manual precisely to avoid unsafe operating conditions, fire, explosion, property damage or personal injury. DANGER Indicates an imminently hazardous situation which, if not avoided, could result in severe injury or death.
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WARNING WARNING This appliance can be used by children aged from 8 years and above and persons with reduced physical, sensory or mental capabilities or lack of experience and knowledge if they have been given supervision or instruction concerning use of the appliance in a safe way and understand the hazards involved.
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CAUTION DANGER Do not turn on the boiler unless ● the water and gas supplies are fully opened. Doing so may damage the boiler. Do not turn on the water if the cold ● BURN water supply shut-off valve is closed. Doing so may damage the boiler.
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The Codes of good practice and regulations refer to the latest versions of the same. Navien ensures that this product contains no harmful The installation must also comply with the following European substances and that no harmful materials have been used in its Standards: manufacture.
If it seems like there is a problem, do not use the boiler. Contact your supplier. Keep the included items out of the reach of children, as they can be dangerous. When you no longer wish to use the boiler, disable any parts that could be potentially hazardous. KD Navien NCB-24LDWE...
2.3 Technical Data The following table lists the general specifications for the boiler. NCB500-1.5S/37K NCB500-2S/41K Specifications Unit Heat input range 26.8/4.6 26.8/4.6 DHW heat input range 37.0/4.6 41.0/4.6 Heat output range @ 80/60°C 26.0/4.5 26.0/4.5 DHW output range 37.0/4.6 37.0/4.6 Condensing heat output range @ 50/30°C...
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The following table lists the product information requirements (EU regulation No 811/2013 and No 813/2013) Specifications Unit NCB500-1.5S/37K NCB500-2S/41K Condensing boiler Low-temperature (**) boiler B1 boiler Cogeneration space heater Combination heater Rated heat output rated Seasonal space heating energy efficiency η...
The following diagram shows the key components of the boiler. Component assembly diagrams and particular parts lists are included in the Appendices. Fan & Motor Ignitor & Flame Rod Front Panel Gas Valve Circulation Pump NCB700-54C NCB500-1.5S/37K NCB500-2S/41K About the Boiler...
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Mixing Chamber Single Venturi Primary Heat Exchanger Secondary Heat Exchanger Gas Valve 3-Way Valve Return Adapter Filter Assembly Pressure Relief Valve Central Heating Supply Central Heating Return DHW Outlet DHW Inlet NCB500-1.5S/37K NCB500-2S/41K About the Boiler...
Cold water inlet (DHW) 15 mm Central heating return 22 mm Overhead View Bottom View 197.5 mm 163 mm 163 mm 41 mm 41 mm 75 mm 75 mm 103.7 mm 103.7 mm 94 mm 94 mm NCB500-1.5S/37K NCB500-2S/41K About the Boiler...
2.6 Operating Modes Exhaust Air In Air In 2.6.1 Operating in Central Heating Mode To operate the central heating mode: Ignitor Blow Fan 1. Press the Menu button ( ) to access the Main menu and select “2. Central Htg Operation” by pressing the OK button Heat Exchanger Circulation...
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The following table lists the central heating temperature When there is no further DHW demand, the burner ● range by k-factor setting value and the applicable outdoor switches off and the 3-way valve remains in DHW mode temperature range. position during a wait time (5 minutes by default), so that it can work more efficiently and provide more flexibility if the taps are continuously turned on and off.
2.7 Installation Procedure The flow diagram below provides a step-by-step description of the recommended procedure for clear, easy installation of the NCB500 boiler in its final location. A detailed description is given of the procedure in the sequenced sections below: Wall-mounting »...
Installing the boiler in a location Carefully consider the following factors when choosing an without a drain will void the warranty and Navien will not be installation location: responsible for water damage that occur as a result. For more information about condensate drainage, refer to “4.3 Connecting...
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Adequate installation clearances Clearance from: Indoor Installation 250 mm minimum CAUTION Front 600 mm minimum Bottom 200 mm minimum Do not install the boiler on carpeting. Sides 5 mm minimum Install the boiler in an area that allows for service and maintenance access to utility connections, piping, filters, Clean, debris and chemical-free combustion air and traps.
3.2 Mounting the Boiler to the Wall WARNING Navien NCB500 boilers come with an upper mounting bracket that is pre-drilled at 400 mm on center for easy installation on The boiler is heavy. Always lift the unit with assistance. Be ●...
For correct installation, all the requirements and recommendations described in the The primary and secondary heat exchangers of the Navien Regulation for Heating Installations in Buildings (RITE) must NCB500 boiler are designed to attain the highest level of be complied with, together with all other national and/or local heat transfer in a compact design.
Use only pipes, fittings, valves, and other components (such ● as solder), that are approved for use in potable water systems. The Navien NCB500 boiler provides domestic hot water Tighten the connection valves with care to avoid damage. ● continuously when flow is sensed by the flow sensor. This Keep the hot water piping system as short as possible, to ●...
Before connecting the condensate drain, choose one of the To connect the condensate drain: following disposal options: 1. Connect a drain line to the condensate trap. The condensate trap outlet will allow 21.5 mm. Use only corrosion-resistant material for the drain line, such as PVC or CPVC.
4.5 Pressure Relief Valve 4.7 Testing the Water System The requirements recommended for the pressure relief valve are as follows: WARNING The pressure relief valve is calibrated to be activated at a ● maximum pressure of 3 bar, and all the pipes and connections Ensure that the boiler is full of water before firing the burner.
5. Connecting the Gas Supply To connect the gas supply: WARNING 1. Connect the gas supply pope to the connection located on the underside of the appliance. If a gas type other than the one specified on the boiler ● reference plate is used, it could cause a fire or even an 2.
5.1 Gas Pipe Material 5.3 Measuring the Inlet Gas Pressure WARNING WARNING The boiler must be left running for 10 minutes before The boiler cannot function properly without sufficient inlet checking the gas pressure, to obtain thermal equilibrium. gas pressure. Measuring the inlet gas pressure should be performed by a licensed professional only.
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3. Leave the faucet on until the boiler shuts down due to a lack 5. Loosen the screws indicated in the figure below and of gas supply, and then turn off the hot water faucet. connect a manometer to the pressure port. Reset the manometer to zero before use.
6. Flue System The minimum distances between the flue exhaust terminal and the building elements must comply with those shown in the WARNING following table: Improper flue of the boiler can result in excessive levels of carbon monoxide, which can lead to severe personal injury. Flue should be performed only by a licensed professional.
6.2.1 Horizontal Coaxial Removal (Type C For vertical ducts, the outlet must be at least 60 cm Note ● from any opening. The dimensions (B, C, D, and E) may be reduced to ● Standard Removal System 25 mm, as long as the flue terminal is extended to clear any overhangs.
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6.2.2 Vertical Coaxial Removal (Type C Standard Removal System Ø60/100 => Max. length: A+B-(1 x 45°elbow) = 8-1 = 7 m Ø60/100 => Max. length: A = 8 m Ø80/125 => Max. length: A+B-(1 x 45°elbow) = 27-1 = 26 m Ø80/125 =>...
Carefully study the diagrams representing the different types of removal and select the one that best suits the conditions of your installation. To choose the removal accessories required for each installation, see the list of accessories on the NAVIEN price list. Maximum Total Length Pipe Diameter...
7. Setting the DIP Switches DIP SW2 CAUTION Switch Function Setting Do not remove the front cover unless the power to the Reserve boiler is turned off or disconnected. Failure to do so may result in electric shock. Reserve Reserve The boiler has 2 sets of DIP switches on the main circuit board 5&6 Country...
8. Connecting Electrical Supplies 2. Unfasten the 2 latches (at the top) and remove 2 screws (at the bottom) to remove the front cover and gain access to WARNING the internal components. Improperly connecting the electrical supplies can result in electrical shock and electrocution. Follow all applicable electrical codes of the local authority having jurisdiction.
8.2 Connecting the Power Supply Cables 4. Insert all these elements in the cable gland and press on the lid “A” until the cable is sufficiently fixed in place and the unit To correctly establish the boiler’s electrical connection, follow is sealed.
8.3 Connecting the Switched Live 8.5 Connecting the Outdoor Temperature Sensor The boiler is designed to be connected to a switched live. The switched live cables are to be connected to terminals 5 The boiler is designed to be able to function with an outdoor (Switched Live In) and 6 (AC Live) of the boiler terminal strip.
As the Navien NCB500 boiler has a dedicated connector for the Navien Smart Room Controller on the back of the front panel, terminal connection at the terminal block is not required.
After installing the boiler, review the following checklist. Complete the boiler start-up process by carrying out the checks listed in the table below. If you have additional questions or need assistance with installation, contact an official Technical Assistance Service (TAS), or refer to the technical support section of Navien’s website (www.navien.co.uk). Check Value measured...
10. Operating the Boiler 10.1 Using the Front Panel The front panel allows you to adjust the temperature and view the operating status or error codes. Remove the protective sheet from the front panel before using it. 10.1.1 Icons and Digital Display The icons and digital display on the front panel provide important information required for the boiler’s operation.
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10.1.2 Buttons Using the buttons on the front panel, you can turn on or off the boiler, monitor the current operation status, and set the values required for the boiler’s operation, such as central heating and DHW supply temperatures. Refer to the following table for detailed information. Menu button Back button Access to the Main menu screen.
3. Press the Up button ( ) or the Down button ( ) until the 3. Press the OK button ( ) to select the DHW temperature desired temperature appears on the display. You can adjust ( ). The highlighted section will flash. the temperature while the display is flashing.
10.6 Accessing Basic Menu Items Item Description 8. Inlet Temp Inlet temperature (°C) In the Main Menu screen, you can view the boiler’s operating conditions, configure the central heating and DHW 9. DHW Temp DHW temperature (°C) temperatures, and review error history. Press the Menu button ) to enter the Main Menu screen.
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1: Supply Temperature 5. Central Htg Control 2: Return Temperature Default: Supply Temperature ● Set the heat demand control type for Navien Thermostat, OpenTherm, CH Thermostat 6. CH Heat Demand and Switched Live. Default: Navien Thermostat ● Press the Up button (...
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If you select DHW Schedule, you can select the certain day to 10.6.3 Setting the DHW Operation schedule the central heating modes. To set the boiler’s DHW operation, press the Menu button ( and then select “3. DHW Operation”. Item Description Schedule a command for each 1.
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The schedule settings and checking function cannot Note be used when the Heat Demand function is set to Navien Thermostat. A list of 10 recent errors are displayed on the screen, with the most recent error displayed at the top of the list.
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10.6.6 Viewing Other System Information 10.6.7 Setting the Display Options To view the miscellaneous system information, press the Menu To set the front panel display options, press the Menu button button ( ), and then select “6. EMS Data”. ), and then select “7. Configuration”. Press the Up button ( ) or the Down button ( ) to switch...
10.7 Accessing Advanced Menu Items 10.7.2 Viewing Input and Output Status To view the boiler’s input and output status, press the Back button ( ) and the Menu button ( ) simultaneously for 10.7.1 Viewing Service Information 3 seconds, and then select “2. Input/Output Status”. To view the service information about the boiler, press the Back button ( ) and the Menu button (...
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10.7.3 Setting the Operation Parameters Press the Back button ( ) to return to the previous screen or menu. To set the boiler’s operation parameters, press the Back button ) and the Menu button ( ) simultaneously for 3 seconds, Item Description and then select “3.
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Item Description Item Description Set the central heating Set the service notification minimum heat capacity limit. according to the operating times. Setting range: Central heating ● minimum capacity (%) – Setting range: 300 – 36500 ● 10. CH Min Limit 20.
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10.7.4 Diagnosing the Boiler System Item Description To run a series of test procedures for a system diagnosis, Test the 3 way valve operation. press the Back button ( ) and the Menu button ( The 3 way valve is turned on ●...
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10.7.5 Setting the Special Operation Modes To operate the boiler in special operation modes, press the Back button ( ) and the Menu button ( ) simultaneously for 3 seconds, and then select “5. Special Operations”. Press the Up button ( ) or the Down button ( ) to switch between the operation modes.
10.8 Error Codes When an error code appears on the front panel, refer to the following chart for a definition and possible remedy for the situation. Item Error Code Description Reset E001 Overheating of heat exchanger Manual E003 Ignition failure Manual E004 False flame detection...
11. Maintaining the Boiler 11.1 Cleaning the Boiler 3. Disconnect the power supply from the boiler. 4. Close the gas valve. CAUTION Make sure the boiler is turned off and the power supply is disconnected before cleaning the boiler. The boiler may remain hot for several minutes after it is turned off.
The water that remains in the plumbing lines CAUTION will drain out. Damage due to freezing is not covered by the Navien limited warranty. If the boiler is connected to a circuit that could freeze, the circuit pipes must be suitably insulated. All pipes installed outdoors must be insulated according to applicable legislation.
11.5 Maintenance Schedules If hot water will not flow and you suspect that the boiler is frozen, follow these steps: 1. Press the Power button ( ) on the front panel to turn off Owner maintenance the boiler. Check boiler area ●...
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Addressing the Reported Problems WARNING Inspect any problems reported by the owner and correct before proceeding. Follow the service and maintenance procedures given ● throughout this manual and in component literature shipped with the boiler. Failure to perform the service Inspecting the Installation Area and maintenance could result in damage to the boiler or system.
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Checking the Ignition Ground Wiring WARNING 1. Check that the ground wire is in good condition and securely attached to the boiler casing. Failure to inspect for the above conditions and have them repaired can result in severe personal injury. 2.
4. Label all the wires on the PCB. Included Items: 5. Disconnect all the wires. Gas Orifice (refer to below table) ● 6. Loosen the five screws indicated in the figure. Model NCB500-1.5S/37K Ø6.3 Ø4.9 NCB500-2S/41K Ø6.3 Ø4.9 Table 1. Orifice Size Gas Pressure and Conversion Kit Number Labels ●...
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7. Remove the front panel assembly. 10. Once the gas inlet pipe is detached from the gas valve, find location B - the connection above the gas valve where it is attached to the fan motor assembly. Carefully remove the two screws by hand using a Phillips screwdriver and pull the gas inlet pipe away from the fan assembly to access the gas orifice.
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Navien NCB500 boilers are shipped ready to fire Replace the old Orifice piece with the new part for use with LP natural gas only.
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c. Fully open several hot water fixtures and set the boiler to operate, and proceed Gas Setup Wizard. DANGER For proceeding Gas Setup Wizard for gas type Note selection, refer to “10.3 Start-Up Wizard” on When conversion is required, be sure to set the front ●...
Gas flow Load Kcal/h Max. 22,360 26.0 26.8 2.870 0.273 NCB500-1.5S/37K NCB500-2S/41K Min. 4,040 1.986 0.189 12.2 Cleaning the Heat Exchanger 2. Disconnect the power supply to the boiler. 3. Turn off both gas and water supply to the boiler.
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6. Loosen the three screws holding the front panel and remove 8. Remove the screw connecting the fan motor assembly the front panel. and the mixing chamber, and then remove the fan motor assembly. When removing the front panel, label all wires and Note Remove the four bolts securing the chamber brackets.
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It is important to keep electric parts of the boiler Note ● safe from water. Navien recommends to use a hose. ● If the water pressure of the hose is too high, water ● may splash to other electric parts of the boiler.
3. Run the wires into the device body through the grommet opening. 4. Connect the wires to the terminal block. 5. Attach the cap to the body. Navien Outdoor Temperature Sensor Outdoor Temperature Sensor Installation Guidelines Avoid areas with temperature fluctuations by direct sunlight, ●...
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GAS BOILER SYSTEM COMMISSIONING CHECKLIST This Commissioning Checklist is to be completed in full by the competent person who commissioned the boiler as a means of demonstrating compliance with the appropriate Building Regulations and then handed to the customer to keep for future reference. Failuretoinstallandcommissionaccordingtothemanufacturer’sinstructionsandcompletethisBenchmarkCommissioningChecklistwillinvalidatethe warranty.Thisdoesnotaffectthecustomer’sstatutoryrights.
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SERVICE RECORD It is recommended that your heating system is serviced regularly and that the appropriate Service Interval Record is completed. Service Provider BeforecompletingtheappropriateServiceRecordbelow,pleaseensureyouhavecarriedouttheserviceasdescribedinthemanufacturer’sinstructions. Alwaysusethemanufacturer’sspecifiedsparepartwhenreplacingcontrols. SERVICE 01 SERVICE 02 Date: Date: Engineername: Engineername: Companyname: Companyname: TelephoneNo: TelephoneNo: GassaferegisterNo: GassaferegisterNo: Atmax.rate: COppm AND CO ²...
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