Navien NFC-250/175H Installation Manual
  1. Manuals
  2. Brands
  3. Navien Manuals
  4. Boiler
  5. NFC-250/175H
  6. Installation manual

Navien NFC-250/175H Installation Manual

Condensing combi-boilers
Hide thumbs Also See for NFC-250/175H:
Table of Contents

Advertisement

Quick Links

Installation Manual
NFC-H Condensing Combi-Boilers
Model
NFC-250/175H
NFC-250/200H
NSF/ANSI 372
H
WARNING
If the information in these instructions is not followed exactly, a fire or explosion may result,
causing property damage, personal injury, or death.
Do not store or use gasoline or other flammable vapors and liquids in the vicinity of this or
any other appliance.
WHAT TO DO IF YOU SMELL GAS
Do not try to light any appliance.
●
Do not touch any electrical switch; do not use any phone in your building.
●
Immediately call your gas supplier from a neighbor's phone. Follow the gas supplier's instructions.
●
If you cannot reach your gas supplier, call the fire department.
●
Installation and service must be performed by a qualified installer, service agency or the gas
supplier.
The installation must conform with local codes or, in the absence of local codes, the
National Fuel Gas Code, ANSI Z223.1/NFPA 54 and/or CSA B149.1, Natural Gas and Propane
Installation Code.
Keep this manual near this boiler for future reference
whenever maintenance or service is required.
* The wetted surface of this product contacted by consumable
water contains less than one quarter of one percent (0.25%) of
lead by weight.

Advertisement

Table of Contents
loading

Related Manuals for Navien NFC-250/175H

Summary of Contents for Navien NFC-250/175H

  • Page 1 Installation Manual NFC-H Condensing Combi-Boilers Model NFC-250/175H NFC-250/200H Keep this manual near this boiler for future reference whenever maintenance or service is required. NSF/ANSI 372 * The wetted surface of this product contacted by consumable water contains less than one quarter of one percent (0.25%) of lead by weight.
  • Page 2 Requirements for the State of Massachusetts NOTICE BEFORE INSTALLATION This appliance must be installed by a licensed plumber or gas fitter in accordance with the Massachusetts Plumbing and Fuel Gas Code 248 CMR Sections 4.00 and 5.00. IMPORTANT: In the State of Massachusetts (248 CMR 4.00 & 5.00) For all side wall horizontally vented gas fueled equipment installed in every dwelling, building or structure used in whole or in part for residential purposes, including those owned or operated by the Commonwealth and where the side wall exhaust vent termination is less than seven (7) feet above finished grade in the area of the...

  • Page 3: Table Of Contents

    9. Installing a Common Vent System 88 1.6 Rating Plate 9.1 About the Common Vent System 2. Installing the Boiler 9.2 Navien Common Vent Collar Kit (Back- draft Damper) 2.1 Removing the Wood Pallet from the boiler 15 9.3 Starting the Common Vent System 2.2 Choosing an Installation Location...
  • Page 4 Safety Information The following safety symbols are used in this manual. Read and follow all safety instructions in DANGER this manual precisely to avoid unsafe operating conditions, fire, explosion, property damage, personal injury, or death. DANGER Indicates an imminently hazardous situation which, if not avoided, could result in severe injury or death.
  • Page 5 California law requires the following Prop 65 warning to be provided: WARNING WARNING Cancer and Reproductive Harm - www.P65Warnings.ca.gov. CAUTION Do not turn on the boiler unless the water ● and gas supplies are fully opened. Do not store or use gasoline or other ●...
  • Page 6 DANGER DANGER This boiler’s DHW temperature is set to 120°F (49°C) at the factory for your safety and comfort. Increasing the temperature increases the risk of accidental scalding. Water temperatures at or above 125°F (52°C) can cause instant scalding, severe burns, or death. Before you decide to change the temperature setting, read the following charts carefully.

  • Page 7: About The Boiler

    High Altitude Conversion Kit Propane Conversion Kit* (Natural Gas Only)* Outdoor Temperature Air Vent Bushing Sensor and Cable (3/4in to 1/2in) Navien Manifold System NaviClean Universal Temperature Condensate Trap Sensor HotButton Push Button HotButton Wall Plate The Universal Temperature Sensor can...

  • Page 8: Specifications

    3. The net AHRI water ratings shown are based on a piping and pickup allowance of 1.15. Consult Navien before selecting a boiler for installations having unusual piping and pickup requirements, such as intermittent system operation, extensive piping system, etc.
  • Page 9 The NFC-H boiler is equipped with an internal circulation pump. The following table provides detailed information on the pump used for the boiler and the performance curve. Item Pump Model NFC-250/175H, NFC-250/200H Grundfos UPS 15-78 CIAO2 Internal Recirculation Pump (Part Number: 30023987A)
  • Page 10 General Specifications Item NFC-250/175H NFC-250/200H Dimensions 17.3 in (W) x 17.3 in (D) x 33.5 in (H) Boiler Weight 141 lb (64 kg) Boiler Weight with Water 170 lb (77 kg) Installation Type Indoor Wall-Hung Venting Type Forced Draft Direct Vent...

  • Page 11: Components

    1.4 Components The following diagram shows the key components of the boiler. Component assembly diagrams and particular parts lists are included in the Appendixes. Exhaust Intake Air Duct PRV-Air Vent Vent Installation Connection Detector Mixing Chamber Fan & Motor Igniter Assembly Flame Rod Dual Venturi...
  • Page 12 Intake Air Filter Mixing Chamber Fan & Motor Assembly Dual Venturi Igniter Flame Rod Igniter Transformer Gas Valve Fire-Tube Type Heat Exchanger Air Intake Pipe Gas Pipe ASME Name Plate Front Panel Terminal Block Circulation Pump Power Switch Mixing Valve Water Adjust Valve DHW Exchanger 3-Way Valve...

  • Page 13: Dimensions

    1.5 Dimensions The following diagrams show the dimensions of the boiler and the table lists the supply connections. Supply Connections Description Diameter Air Intake 2 in Exhaust Gas Vent 2 in PRV-Air Vent Connection Heating Supply 1 in Heating Return 1 in Gas Connection Condensate Outlet...

  • Page 14: Rating Plate

    1.6 Rating Plate The Navien NFC-H boilers come from the factory configured for use with Natural Gas (NG). Before starting the installation, check the rating plate located on the side of the boiler to ensure that the boiler matches the gas type, gas pressure, water pressure, and electrical supply available in the installation location.

  • Page 15: Installing The Boiler

    2. Installing the Boiler 2.1 Removing the Wood Pallet 2. Remove the accessory box, the wood pallet, the upper container, and the lower pad. from the boiler After you open the box, remove the wood pallet and the pallet brackets and then install the boiler. Upper Container CAUTION...

  • Page 16: Choosing An Installation Location

    2.2 Choosing an Installation Location CAUTION Keep the removed screws in a safe place. The When choosing an installation location, you must screws will be used again in Step 5. ensure that the location provides adequate clearance for the boiler, adequate venting and drainage options, and sufficient access to gas, water, and electrical supplies.
  • Page 17 Navien will not be responsible for times for hot water, installation of a recirculation water damages that occur as a result. For more line which circulates domestic hot water back to the information about condensate drainage, refer to “3.3...

  • Page 18: Mounting The Boiler To The Wall

    2.3 Mounting the Boiler to the Side Back Wall Navien NFC-H boilers come with an upper mounting bracket that is pre-drilled at 16 in (400 mm) on center for easy installation on standard wall studs. Side Front...
  • Page 19 3. Install two set screws through the bracket at the bottom of the boiler to secure the boiler on the CAUTION wall. Ensure that the structure of the installation ● location is sturdy enough to support the full weight of the installed boiler, including the water contained in the heat exchanger and related piping.

  • Page 20: Installing The System Piping

    During the The fire-tube type heat exchanger of the Navien assembly of the heating system, it is important NFC-H boiler is designed to attain the highest level to keep the inside of the piping free of any debris of heat transfer in a compact design.
  • Page 21 System Pressure The Navien NFC-H boiler is intended solely for ● use in pressurized closed loop heating systems operating with 12-80 psi water pressure at the boiler outlet.
  • Page 22 3.1.2 Essential Elements in a Space The following figure illustrates an example of installation using the PRV-air vent adapter. Heating System Pressure Air Vent Relief Valve Air Vent The vent efficiently removes the air from the boiler. The following figure illustrates an example of a typical air vent installation.
  • Page 23 Adapter. The following illustration shows an example of a separately installed external LWCO Internal LWCO using the PRV-air vent adapter. The Navien NFC-H boiler is equipped with a factory- installed, pressure-sensing type low water cutoff External LWCO (LWCO) appliance. The minimum operation pressure for this appliance is 6 psi by default.
  • Page 24 Expansion Tank Pressure Relief Valve An expansion tank must be installed in the space To complete the space heating system installation, heating piping to prevent excessive pressure you must install a in, 30 to 80 psi (max) pressure from building in the system. See the examples of relief valve on the space heating hot water outlet.
  • Page 25 80 psi can be used. The Navien manifold system allows for easy separation of the Boiler-Primary loop from the WARNING System-Secondary loop(s). Refer to the following...

  • Page 26: Installing A Domestic Hot Water (Dhw) System

    Refer to the following illustration for Note details on installing the NFC-H Manifold System (Part Number: 30026576A) to the With its multi-purpose design, the Navien NFC-H valve kits. boiler provides hot water on demand. This means that the boiler produces DHW only when the user demands it.
  • Page 27 Relief DHW Heat Exchanger Valve The DHW heat exchanger installed inside the Navien NFC-H boiler has been tested and certified in accordance with the latest IAPMO standard PS 92. CAUTION Drain and Isolation Valves Install the pressure relief valve as close to the boiler as possible.

  • Page 28: Connecting The Condensate Drain

    3.2.3 DHW System Piping 3.3 Connecting the Condensate Drain CAUTION The Navien NFC-H boiler creates condensation when it operates. This condensation has an acidic To comply with ASME or CRN requirements, pH of 3-5. Follow all local codes and regulations an additional high temperature limitation when disposing of condensate from the boiler.
  • Page 29 2. Insert the condensate trap to the drain adapter Before connecting the condensate drain, choose at the bottom of the boiler. one of the following disposal options: 3. Attach the clip to the condensate trap. a. From the boiler directly into an external drain.
  • Page 30 If the pH level is not specified, replace the neutralizing media when the pH is below 6.0. For replacement media, contact your local Navien distributor. As part of this annual maintenance procedure, make sure to clean out the condensate trap which may contain excess debris.
  • Page 31 ● the neutralizer. If option ‘b’ (p. 28) is selected as the disposal option, the Navien condensate neutralizer kit is recommended. The condensate from the appliance flows through the neutralizing media and increases the pH of the condensate. An increased pH prevents Y-fitting corrosion of the installation’s drainage system and...

  • Page 32: Filling The System

    3.4 Filling the System Before filling the boiler, completely unscrew and remove the air vent cap to enable the system to fill properly. If the air vent cap is only partially Note loosened, the air vent may not allow for the boiler to fully purge.

  • Page 33: Testing The Water System

    3.4.1 Built-in Water Fill Connection 3.5 Testing the Water System The Navien NFC-H boiler is equipped with an auto- feeding water connection and motorized feeding WARNING valve. Therefore, installation of additional system water fill connection is not necessary in most cases.

  • Page 34: Considerations For System Applications

    Read and follow the guidelines listed below when correct pressure will vary with each application. installing system piping for the Navien NFC-H boiler: The typical cold water fill pressure for a residential system is 12 psi. The pressure will rise System application drawings are intended to ●...
  • Page 35 Refer to the “3.7.9 Wiring Diagram - Air Handler” on Air Handler Interface page 54 for wiring connections. The Navien NFC-H boiler can control the operation of an air handler when a thermostat is used in WARNING combination with the air handling unit. The Air...
  • Page 36 Configuring a Zone System 3.6.2 Examples of System Applications Refer to the following examples to properly The NFC-H boiler can control up to 3 zones utilizing implement a system for space heating, DHW zone valves or zone pumps. After installing the supply, or both.
  • Page 37 3.6.3 System Application - Zone System with Pumps (Primary/Secondary Piping) Additional Zone Zone #2 Zone #1 NaviClean Air Separator Not to exceed 4 pipe Dia or Max. 12" Pressure Air Vent Relief Valve Backflow preventer Pressure reducing valve Expansion Tank Make-up Water System application drawings are intended to explain the system piping concept only.
  • Page 38 3.6.4 System Application - Zone System with Zone Valves (Primary/Secondary Piping) Additional Zone Zone #2 Zone #1 Zone Valve System Pump (Typical) NaviClean Air Separator Not to exceed 4 pipe Dia or Max. 12” Make-up Water Backflow preventer Pressure reducing valve Expansion Tank System application drawings are intended to explain the system piping concept only.
  • Page 39 3.6.5 System Application - Air Handler System Pressure Relief Valve Air Vent Air Separator Make-up Water Backflow Expansion Tank preventer Pressure reducing valve Air Flow Air Handler System application drawings are intended to explain the system piping concept only. Note ●...
  • Page 40 3.6.6 System Application - Air Handler System with RS-485 Communication Pressure Relief Valve Separator COMM Cable Make-up Water Expansion Backflow preventer Tank Pressure reducing valve Air Flow Air Handler Thermostat Outdoor Sensor Installing the System Piping...
  • Page 41 3.6.7 System Application - Combi Pre-Heat Mode Combi pre-heat allows NFC-H boilers to pre-heat to ensure a quick supply of hot water when there is no external recirculation system. This mode is enabled by default. (Refer to the combi pre-heat section in “11.5.3 Setting the DHW Operation”...
  • Page 42 3.6.9 System Application - External Recirculation with HotButton and NaviCirc External Recirculation Mode For best performance, select the manual option in the External recirculation DHW recirculation mode. Combi pre-heat is the default mode for DHW recirculation. To select external recirculation, refer to the Note combi pre-heat and external recirculation sections in "11.5.3 Setting the DHW Operation"...
  • Page 43 3.6.10 External Recirculation with Dedicated Return Line (Always On, Weekly, Intelligent) External Recirculation Mode For best performance, select the intelligent or weekly option in the external recirculation DHW recirculation menu. Combi pre-heat is the default mode for DHW recirculation. To select external recirculation, refer to the Note combi pre-heat and external recirculation sections in "11.5.3 Setting the DHW Operation"...
  • Page 44 3.6.11 External Recirculation with HotButton and Dedicated Return Line (HotButton, Aquastat) External Recirculation Mode To use the aquastat mode, install an aquastat to the DHW pipe line and connect to the CNC6 terminal on the PCB. (Refer to “3.7.4 Wiring Diagram - Zone Pump System with DHW Recirculation” on page 48 for details.) CAUTION The aquastat temperature must be set lower than the NFC-H boiler DHW set temperature.

  • Page 45: Examples Of Electrical Connections

    3.7 Examples of Electrical Connections WARNING Improperly connecting the electrical supplies can result in electrical shock and electrocution. Follow all applicable electrical codes of the local authority having jurisdiction. Connecting the electrical components should be performed only by a licensed professional. CAUTION 3.7.2 Wiring Diagram - External LWCO Label all wires before disconnecting them...
  • Page 46 3.7.3 Wiring Diagram - Zone Pump System NFC-H boilers can operate a heating system with up to 3 zones. The following is the wiring diagram for a zone pump system with 3 zones. Without 24VAC Connections lLWCO AC24VL AC24VN Zone pump 1 SUPPLY RETURN OUTDOOR...
  • Page 47 With 24VAC Connections lLWCO AC24VL AC24VN SUPPLY RETURN OUTDOOR T/S_ZONE3 T/S_ZONE2 T/S_ZONE1 Zone pump 1 TEMPERATURE SENSOR SUPPLY RETURN OUTDOOR T/S_ZONE3 T/S_ZONE2 T/S_ZONE1 (max. 2.5 A) TEMPERATURE SENSOR Zone pump 2 (max. 2.5 A) Pump Ground Zone pump 3 Thermostat 3 (max.
  • Page 48 3.7.4 Wiring Diagram - Zone Pump System with DHW Recirculation NFC-H boilers can use both the 3 zone heating system and the DHW recirculation feature. The following wiring diagram shows the 3 zone system and the DHW external recirculation feature. Without 24VAC Connections lLWCO AC24VL...
  • Page 49 With 24VAC Connections lLWCO AC24VL Recirculation pump AC24VN (max. 2.5 A) Recirculation Timer, Aquastat, lLWCO AC24VL AC24VN or HotButton SUPPLY RETURN OUTDOOR T/S_ZONE3 T/S_ZONE2 T/S_ZONE1 Push Button Zone pump 1 TEMPERATURE SENSOR SUPPLY RETURN OUTDOOR T/S_ZONE3 T/S_ZONE2 T/S_ZONE1 (max. 2.5 A) TEMPERATURE SENSOR Zone pump 2 (max.
  • Page 50 3.7.5 Wiring Diagram - Zone Valve System The NFC-H boilers can operate a heating system with up to 3 zones. The following is the wiring diagram for a zone valve system with 3 zones. Without 24VAC connections Zone valve 1 (max.
  • Page 51 With 24VAC connections Zone valve 1 (max. 1A) Zone valve 2 (max. 1A) Zone valve 3 (max. 1A) lLWCO AC24VL Recirculation pump AC24VN (max. 2.5 A) Recirculation Timer, Aquastat, lLWCO AC24VL AC24VN or HotButton SUPPLY RETURN OUTDOOR T/S_ZONE3 T/S_ZONE2 T/S_ZONE1 Push Button TEMPERATURE SENSOR SUPPLY...
  • Page 52 3.7.6 Wiring Diagram - the Navien SmartZone + The Navien Smart Zone + controller may be used with NFC-H boilers to operate a heating system with more than 3 zones. When Navien boilers are used with a Navien Smartzone+ zone pump controller, an RS-485 data communication link is established through the Ready-link connection.
  • Page 53 3.7.7 Wiring Diagram - Generic Zone 3.7.8 Wiring Diagram - Generic Zone System with Zone Valves System with Zone Pumps <NFC-H> <NFC-H> lLWCO lLWCO AC24VL AC24VL AC24VN AC24VN SUPPLY RETURN OUTDOOR T/S_ZONE3 T/S_ZONE2 T/S_ZONE1 SUPPLY RETURN OUTDOOR T/S_ZONE3 T/S_ZONE2 T/S_ZONE1 TEMPERATURE SENSOR TEMPERATURE SENSOR SUPPLY...
  • Page 54 3.7.9 Wiring Diagram - Air Handler <NFC-H> lLWCO AC24VL AC24VN SUPPLY RETURN OUTDOOR T/S_ZONE3 T/S_ZONE2 T/S_ZONE1 TEMPERATURE SENSOR SUPPLY RETURN OUTDOOR T/S_ZONE3 T/S_ZONE2 T/S_ZONE1 TEMPERATURE SENSOR <Air Handler> Connect the pump wires to the system pump. <NFC-H> lLWCO AC24VL AC24VN SUPPLY RETURN OUTDOOR...
  • Page 55 For best performance, wrap the sensor and pipe section with thermal insulation. ● A single temperature sensor is supplied with the boiler. Additional temperature sensors are ● available for purchase. Contact Navien for more information. Installing the System Piping...

  • Page 56: Connecting The Gas Supply

    This boiler cannot be converted from natural ● gas to propane or vice versa without a Navien gas conversion kit. Do not attempt a field conversion of this boiler without a Navien gas conversion kit. Doing so will result in dangerous operating conditions and will void the warranty.
  • Page 57 BTUs. Also, ensure that the flexible line has no crimps or tight bends in it, as this will restrict gas flow. Gas Supply When using rigid pipe, Navien ● recommends the installation of a union on the gas supply line close to the boiler, to facilitate any future maintenance or service.
  • Page 58 Typical LP Gas piping examples: 2 Stage System with Multiple Regulators (Recommended) Gas Regulator (2 Stage) High Pressure Low Pressure Regulator Regulator (before entering home or building) Gas Tank Full size Gas Pipe Single Regulator System Gas Regulator (12” WC) Full size Pipe Gas Pipe...

  • Page 59: Gas Pipe Sizing Tables

    4.1 Gas Pipe Sizing Tables The following tables are referenced from the 2012 National Fuel Gas Code and are for reference only. Please consult the gas pipe manufacturer for actual pipe capacities. Maximum Natural Gas Delivery Capacity In Cubic Feet (ft ) per Hour (0.60 Specific Gravity;...

  • Page 60: Measuring The Inlet Gas Pressure

    Maximum Liquefied Propane Delivery Capacity In Thousands of BTU/H (0.5 in WC pressure drop) Length (including fittings) Pipe 10 ft 20 ft 30 ft 40 ft 50 ft 60 ft 80 ft 100 ft 125 ft 150 ft 175 ft 200 ft 250 ft Size...
  • Page 61 To measure the inlet gas pressure: 8. Unfasten the 4 latches (2 at the top and 2 at the bottom) to remove the front cover and gain 1. Shut off the manual gas valve on the gas supply access to the internal components. line.

  • Page 62: Venting For Combustion Air

    5. Venting for Combustion Air Additional Guidelines for Combustion Air Corrosive Contaminants Combustion air piping to the outside is Muriatic acid/hydrochloric acid ● recommended. (Direct Venting) Refrigerant leaks The boiler may be installed with a single pipe ● carrying the flue products to the outside while Chlorine-type bleaches, detergents, and cleaning using combustion air from the equipment room.

  • Page 63: Venting The Boiler

    5.1 Venting the Boiler The boiler must be properly vented to ensure a constant supply of clean intake air and to ensure that exhaust air is properly removed from living areas. When venting the boiler, follow these DANGER guidelines: Do not install the boiler in areas with This appliance is certified as a “Category IV”...
  • Page 64 Connecting the Pipe to the Vent Collar Mark 3.0” from Do not use primer or cement on the Note the end of the pipe appliance connection. 3.0” WARNING When cutting the vent pipe, ensure that the cutting plane of the pipe is at a 90° angle with the pipe axis and is as flat as possible.

  • Page 65: About The Vent Installation Detector

    CAUTION DANGER Do not start the vent run with a street elbow at If the connections leak, harmful flue gas may the vent collar. Using an elbow directly at the cause personal injury or death. after completing collar will not allow for a tight seal between the the installation and filling the boiler with water, appliances and vent pipe.
  • Page 66 Purpose WARNING The VID’s purpose is to guide the installer to fully insert the vent pipe to a depth of at least 3.0 inches The list above does not represent an ● or 76 mm, into the collar. If the vent pipe is not exhaustive list of situations that may prevent properly inserted and installed, it could separate proper operation of the VID.
  • Page 67 WARNING The vent installation detector Detectable Undetectable Venting for Combustion Air...

  • Page 68: Selecting A Vent Type

    5.3 Selecting a Vent Type All Navien boilers are Category IV appliances and prepared at the factory to be direct vented (sealed combustion). Navien recommends direct air vent installations whenever possible to avoid back drafting cold air through the boiler unit. If you cannot use a direct vent, ensure that an ample supply of make-up air is available in the installation location.
  • Page 69 Canadian Direct Vent US Direct Vent Description Installations Installations Vertical clearance to ventilated soffit located above the terminal within a horizontal distance of 2 ft (61 cm) from the center line of the terminal Clearance to unventilated soffit Clearance to outside corner Clearance to inside corner 3 ft (91 cm) within a Clearance to each side of center line extended...
  • Page 70 6 in (H) or in (H) which occurs from back drafting will not be covered 9 in round by the Navien warranty. If there is any question 53 in 210 in about the possibility of back drafting in the NFC-...
  • Page 71 Canadian Non-Direct US Non-Direct Vent Description Vent Installations Installations Clearance above grade, veranda, porch, deck, 12 in (30 cm) 12 in (30 cm) or balcony 48 in (120 cm) below or Clearance to window or door that may be 36 in (91 cm) to side of opening;...
  • Page 72 Canadian Non-Direct US Non-Direct Vent Description Vent Installations Installations 36 in (91 cm) above Clearance to a mechanical air supply inlet 6 ft (1.83 m) if within 10 ft (3 m) horizontally Clearance above paved sidewalk or paved 7 ft (2.13 m) †...

  • Page 73: Selecting Vent Pipe Materials

    5.4 Selecting Vent Pipe Materials When you set PCB DIP SW2 (Set of 8 Note Switches) #8 to On, ensure that CPVC, polypropylene or stainless steel piping Venting requirements differ in the US and Canada. is used for exhaust venting. Consult the following chart or the most recent edition of ANSI Z223.1/NFPA 54 or CAN/CGA B149.1, as well as all applicable local codes and regulations...

  • Page 74: Measuring Vent Length

    5.5 Measuring Vent Length Centrotherm Innoflue® (Flexible) (Certified to UL1738 and ULCS636) IFVL02xxx (2”) or IFVL03x xx (3”) The maximum vent length when using 2 in exhaust IFSFC02 or IFSFC03 (2” or 3” Rigid-to- Flex Male ducts is 65 ft (20 m). The maximum vent length Adapter) when using 3 in vent ducts is 150 ft (45 m).

  • Page 75: Terminating The Vent

    5.6 Terminating the Vent Centrotherm Innoflue® (Certified to UL1738 and ULCS636) ISELL0287 or ISELL0387 (2” or 3” 87° Elbow) Before installing the boiler, determine what type of ISELL0245 or ISELL0345 (2” or 3” 45° Elbow) vent termination is appropriate for the installation IST02 or IST03 (2”...
  • Page 76 Indoor Boiler Installation Venting Two-pipe Vertical Venting - Intake and exhaust ● pipes do not have to terminate in the same area. Examples Exhaust Gas The following are some possible indoor venting 36” (900 mm) min. options: 12” (300 mm) min. Two-Pipe Sidewall Venting ●...
  • Page 77 Indoor Boiler Installation Venting Concentric Sidewall Venting ● Examples (Continued) Combustion Air Intake Low Profile Two-Pipe Sidewall Venting* ● Combustion Air Intake Exhaust Exhaust Exhaust Intake Air (from (from outdoors) 1" (25 mm) min. appliance) Maintain 12” (300 mm) min. clearance above highest anticipated snow level or grade, whichever is greater Concentric Vertical Venting ●...
  • Page 78 Model Type Dia. Centrotherm Innoflue Flex NFC-250/200H 2 in 50 ft NFC-250/175H Only the flexible vent models listed above are ● approved for use with this appliance. All flexible vent pipe must be installed ● VERTICALLY through the roof. No horizontal terminations are permitted.

  • Page 79: Setting The Dip Switches

    The DIP SW1 (Set of 6 Switches) on the circuit board configures the operation status and model settings. Switch Function Setting Normal Operation 1-OFF, 2-OFF 2-stage MAX 1-ON, 2-OFF 1 & 2 Operation Status 1-stage MIN 1-OFF, 2-ON 1-stage MAX 1-ON, 2-ON NFC-250/200H 5-OFF, 6-OFF 5 & 6 Model Setting NFC-250/175H 5-ON, 6-OFF Setting the DIP Switches...

  • Page 80: Dip Switch 2 (Set Of 8 Switches)

    6.2 Dip Switch 2 (Set of 8 Switches) The DIP SW2 (Set of 8 Switches) on the circuit board configures the gas type, altitude, temperature control modes, country, and enables or disables the space heating thermostat. Switch Function Setting Comment Natural Gas 1-OFF Gas Type...

  • Page 81: Connecting The Power Supply

    ● power supply. Doing so will damage the boiler CAUTION and void the warranty. All the Navien NFC-H boilers are supplied with a ● Label all wires before disconnecting them factory-installed, 3-pronged (grounded) plug. The when you work on the controls. Wiring errors boiler’s current rating is 12 A and can be plugged...

  • Page 82: Installing A Cascade System

    Follow all applicable regulations when installing a cascade system. You can connect up to 1 combi-boiler and 15 Navien water heaters (NPE-A2 or NPE-S2 model) to meet high- volume heating demands. Some possible connection options include the following:...
  • Page 83 When linking multiple water heaters to NFC-H combi-boiler, only the main unit can provide space heating and ● sub units must be configured for DHW only (You can set only the NFC-H combi-boiler as the main unit in the cascade system, and the main unit controls the power on/off status of all the sub units in the system). Once turned on by the main unit, the water heaters will operate in stages to satisfy the DHW demands.

  • Page 84: Cascade System - Recirculation System Application Example

    8.2 Cascade System - Recirculation System Application Example When using the cascade system, external recirculation can only be connected to and controlled by the NPE-A2 water heater. Set each individual water heater to the appropriate recirculation mode utilizing the 2-way valve and front panel DIP switches.
  • Page 85 If Recirculation Return Line Is Not Installed Install a NaviCirc valve at the furthest fixture from the water heaters as illustrated below and set the internal 2-way valve on the 1st NPE “A2” unit to the “Ext” position. Refer to the NaviCirc and NPE-A2 Installation Manuals for additional details.

  • Page 86: Connecting The Communication Cables

    You can connect one NFC-H boiler with up to 15 boilers using the Power button ( Navien water heaters (NPE-A2 or NPE-S2 Model), using the Ready-Link communication cables. Select To configure the communication settings: the NFC-H series combi-boiler in the cascading 1.
  • Page 87 3. On the sub NPE-A2 water heater panel, press and hold the OK button ( ) for 3 seconds on the sub unit. Then, the ID 1. Allocated! message will appear on the sub unit’s front panel display. When the water heater is set to a sub unit, the icon will appear on the display.

  • Page 88: Installing A Common Vent System

    9.1 About the Common Vent 9.1.1 Guidelines for a Common Vent System System The Navien Common Vent System* provides an easy way to install the vent system for an NFC-H boiler CAUTION unit and up to 7 NPE water heater units. By sharing...
  • Page 89 Adequate Installation Clearances To avoid moisture and frost build-up and to ● maintain clearances to openings on adjacent homes, 45° elbows, 90° elbows, or tees may be attached to the end of the termination vent pipe CAUTION to direct the exhaust plumes away from buildings, as long as the total allowable vent lengths, Do not install the boiler on carpeting.
  • Page 90 Clean, Debris and Chemical-free Cutting and Assembling Common Vent Combustion Air System Components Do not install the boiler in areas where dust and ● Standard tools are suitable for the cutting and debris may accumulate or where hair sprays, assembly of common vent system components. spray detergents, chlorine, or similar chemicals Follow the guidelines listed below when working are used.
  • Page 91 Vent Pipe Pitch and Supports 3. Hold the pipe and pipe fitting together for about 15 seconds until the cement sets. For horizontal runs, slope the horizontal section Use approved solvent type cement Note ● upward toward the vent termination at a rate of ”...
  • Page 92 9.1.2 Determining the Length of a Common Vent Length Table Common Vent System [Total Length (L) = W + H] Follow the instructions listed below to determine the length of a common vent. Vent Lengths for an NFC-H Boiler with up to 1.

  • Page 93: Navien Common Vent Collar Kit (Back-Draft Damper)

    (Direct Vent Only) The following illustration depicts an example of a Common Vent Collar common vent system installed for a cascade system of 1 combi-boiler (NFC-H Model) and 7 Navien water heaters (NPE Model). Con den sing Wat Co m m...

  • Page 94: Starting The Common Vent System

    Maintenance Port 9.3 Starting the Common Vent System Navien Common Vent Collar Kit has a maintenance port to allow you to easily inspect the operating condition of the damper plate. 9.3.1 Common Vent Collar Kit Assembly Follow the instructions below to assemble the Common Vent Collar Kit on the NFC-H boiler unit: 1.
  • Page 95 9.3.2 Connecting the Pipe to the 4. Tighten the four mounting screws to secure the Common Vent Collar Kit in place. The screws (x Common Vent Collar Kit 4) are supplied with the Common Vent Collar Kit. WARNING When cutting the vent pipe, ensure that the cutting plane of the pipe is at a 90°...
  • Page 96 9.3.3 Assembling the Wye Joint 2. Insert the vent pipe into the vent collar to start the vent run. Make sure to completely slide the vent into the collar until the end makes contact 1. Assemble the hub wye, the 2” reducer, and the with the bottom of the socket.
  • Page 97 2. Assemble the wye joint or wye assembly to the vent pipe. Apply solvent cement to the mating DANGER surfaces. If the connections leak, harmful flue gas may cause personal injury or death. After completing the installation and filling the water heater with water, turn on the boiler and test for leaks using a bubble test kit.

  • Page 98: Connecting And Terminating The Vent Pipe

    9.4 Connecting and Terminating the Vent Pipe Refer to the following example to install the common vent system. The installation area should be measured to ensure that sufficient space is available to install the boiler units and the common vent system. Ensure that the common vent system is installed near the boiler units while satisfying all clearance requirements that are specified in this manual as well as the Installation Manuals supplied with the boiler units.

  • Page 99: Setting Up The Common Vent System

    9.5 Setting up the Common Vent 9.6 Common Vent Termination System Clearances Refer to the following figures when setting the common vent type. 9.6.1 Direct Vent Application – Vertical Installation To view and configure the cascade settings, press the Back button ( ) and the Menu button ( simultaneously for 3 seconds, and then select 36"...
  • Page 100 9.6.3 Direct Vent Application – Horizontal Installation i n . m ) m 0 0 m 1 2 " ( 3 Exhaust Maximum Exhaust Gas length 20’ (6 m) Minimum length 36” Intake Intake Air (91 cm) In cases where a 12” horizontal clearance is not The illustration is intended for Note ●...

  • Page 101: Installing A Condensate Drain

    9.7 Installing a Condensate Drain To install a condensate drain to the common vent system: Refer to the following examples to install a 1. Form a loop with a drain hose and fix it with a condensate drain hose (field supplied) to the tie.

  • Page 102: Maintenance

    9.8 Maintenance 3. Reinstall the gasket and maintenance port cover, and then fix them with a set screw. Periodically check the damper condition inside the Common Vent Collar Kit through the maintenance port to ensure optimal performance of the system. Follow the instructions to check the damper condition and replace the Common Vent Collar Kit if necessary.

  • Page 103: Installation Checklist

    “Troubleshooting” in the Owner’s Manual. If you have additional questions or need assistance with installation, contact Technical Support at 1-800-519- 8794 or 1-949-420-0420, or refer to the technical support section of Navien’s website (www.navieninc.com). Installing the boiler...
  • Page 104 Connecting the Space Heating Piping Has the system been filled (less than 80 psi) and purged of air? Does the piping incorporate means for air removal (scoop, separator, etc.)? Is there an expansion tank installed and set to the proper system pressure? If glycol is used, is it propylene at a concentration of 50% or less? If an external low water cut off (LWCO) is installed, is it wired to the boiler? Connecting a Pressure Relief Valve...
  • Page 105 Venting the boiler Is the vent termination at least 12 in (300 mm) above the exterior grade? Have you ensured that sufficient make-up air is available? Is the total vent length within the maximum vent length restriction? Connecting the Power Supply Is the supplied voltage 110-120V AC? Is the boiler plugged into a properly grounded outlet? If you have made a direct power supply connection, have you installed a power switch to...

  • Page 106: Operating The Boiler

    11. Operating the Boiler 11.1 Operating the Boiler for the First Time FOR YOUR SAFETY READ BEFORE OPERATING WARNING: If you do not follow these instructions exactly, a fire or explosion may result, causing property damage, personal injury or loss of life. A.

  • Page 107: Turning The Boiler On Or Off

    11.2 Turning the Boiler On or Off WARNING To turn the boiler on or off, press the Power button Ensure that the boiler is filled with water ● before turning on the boiler for the first time. Turning on a boiler that is not filled will damage the boiler and result in property damage, severe personal injury, or death.

  • Page 108: Start-Up Wizard

    11.3 Start-Up Wizard 10. Set the Combi-Pre heat mode(Combi Pre-heat select) The start-up wizard should run the first time the Always On/Intelligent/Weekly ● unit is powered on. The wizard must be completed 11. Set the External Recirculation mode(External before the boiler can be used. Recirculation select) 1.

  • Page 109: Adjusting The System Temperatures

    11.4 Adjusting the System 5. Press the Back button ( ) to return to normal operation mode, or rotate the Command dial Temperatures ) to adjust other operation conditions. You can adjust the temperature while the highlighted section is flashing. Once the flashing 11.4.1 Adjusting the Space Heating stops, the current temperature setting is stored.

  • Page 110: Accessing Basic Menu Items

    11.4.3 Resetting the Boiler 2. Rotate the Command dial ( ) to the right to select the DHW temperature. If an error message appears during boiler operation, reset the boiler to resolve the problem. Press the Back button ( ) on the front panel to reset the boiler.
  • Page 111 11.5.1 Viewing Basic Information Item Description To view information about the boiler, press the System supply temperature 8. Sys Supply Temp Menu button ( ), and then select “1. Status (°F) Information”. System return temperature 9. Sys Return Temp (°F) Heat exchanger outlet 10.
  • Page 112 Press the Back button ( ) to return to the previous Item Description screen or menu. 27. Boost Interval Boost interval set time (min) Item Description Time Set space heating target Sea Level (0 - 2,000 ft) temperature (°F). Level 1 (2,000 - 5,400 ft) The setting range varies ●...
  • Page 113 Default: 0 min ● 6. Radiators (48.5–76.5°C) (38–59°C) Enable or disable heating 104–180°F 86–149°F User- zones utilizing the Navien 7. Custom (40–82°C) (30–65°C) defined Zone Controller. 4. Navien Zone Controller Setting range: Enabled/ Heat loads 1-6 show the preset temperature ranges ●...
  • Page 114 11.5.3 Setting the DHW Operation Item Description To set the boiler’s DHW operation, press the Menu When only one NFC-H boiler is button ( ), and then select “3. DHW Operation”. connected: Set the Recirculation type and Schedule settings. Recirculation type ●...
  • Page 115 Combi Pre-Heat External Recirculation When using the combi pre-heat feature, you When using the External Recirculation feature, you can choose commands in the menu to preheat can choose commands in the menu to preheat according to the set DHW temperature. according to the set DHW temperature.
  • Page 116 When Installing the Cascade System Set the Weekly Schedule When using the recirculation feature in the cascade When setting up the Weekly option, select ‘Weekly, ’ system, you can choose commands in the menu and select between 1 Day, 3 Day, and 7 Day to go to to preheat according to the set DHW temperature.
  • Page 117 Press the Back button ( ) to return to the previous Rotate the Command dial ( ) to switch between screen or menu. the list of errors. Press the Command dial ( ) to select an error to view detailed information. Item Description 1.

  • Page 118: Accessing Advanced Menu Items

    Press the Back button ( ) to return to the previous Item Description screen or menu. Select a temperature unit. Item Description 1. Celsius (°C) 2. °C/°F 2. Fahrenheit (°F) Setting 1. Elapsed Default: Fahrenheit (°F) Time After Elapsed time since installation ●...
  • Page 119 11.6.2 Viewing Input and Output Status Item Description To view the boiler’s input and output status, press 10. Zone V/V Zone 2 valve output status the Back button ( ) and the Menu button ( 2 status simultaneously for 3 seconds, and then select “2. 11.
  • Page 120 Item Description Set the space heating return minimum temperature. 3. Return MIN Setting range: 68°F (20°C) – ● Set-point [MAX Set-point – 18°F (10°C)] Default: 86°F (30°C) ● Set the space heating return maximum temperature. 4. Return MAX Set- Setting range: [MIN Set-point + ●...
  • Page 121 Item Description Item Description Set the delay time for the burner Set the space heating pump 18. Boiler to operate when there is a call for over-run time. 11. Zone Pump heat for a zone valve. T/S Start-up Setting range: 3 – 40 min ●...
  • Page 122 * The anti-fast cycling time is the duration that the boiler Item Description stops its space heating operation when the space heating supply or return temperatures reach the set Set the service notification values for boiler operation stop temperatures. The according to the operating times.
  • Page 123 Item Description Item Description To enter the Cascade Main Set the cascade protocol. ● 4. Cascade setting mode, select Start. NPE or NR ● Protocol The setting mode is entered ● Default : NPE ● and the IDs of all boilers that 5.
  • Page 124 11.6.6 Diagnosing the Boiler System Press the Back button ( ) to return to the previous screen or menu. To run a series of test procedures for a system diagnosis, press the Back button ( ) and the Menu Item Description button ( ) simultaneously for 3 seconds, and then...
  • Page 125 Item Description Item Description Test the Zone 1 pump operation. Test the Flow control valve operation. Rotate the valve from The Zone 1 pump is turned on ● its current position to fully open as soon as you enter the test 3.
  • Page 126 11.6.7 Setting the Special Operation 11.6.8 Operating in Air Purge Mode Modes To operate the boiler in air purge mode, press the Back button ( ) and the Menu button ( To operate the boiler in special operation modes, simultaneously for 3 seconds, and then select “8. Air press the Back button ( ) and the Menu button Purge Mode”.

  • Page 127: Understanding Error Codes

    11.7 Understanding 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. Error Code Reason Self-diagnostic/Action Manual RESET E001 Heatexchanger over temperature Auto RESET E003 Ignition failure Manual RESET Manual RESET...
  • Page 128 Error Code Reason Self-diagnostic/Action Manual RESET E615 Abnormal operation: input and memory Auto RESET Alarm E736 Abnormal operation: cascade communication Alarm Abnormal operation: outdoor temperature sensor (appears only E740 Alarm when the outdoor reset curve is enabled). E761 Abnormal Operation: Pre-Heat Aquastat Alarm E762 Abnormal flue gas duct: Vent pipe not properly inserted...

  • Page 129: Appendixes

    ● without an officially approved conversion kit mixes an odorant with the propane to make and the instructions supplied by Navien. Gas its presence detectable. In some instances the & High Altitude conversion using any other odorant can fade, and the gas may no longer parts will result in extremely dangerous burner have an odor.
  • Page 130 Gas Orifice (Table 1) access to the internal components. See Figure 1 ● for illustration of the front cover clamps. Gas Pressure and Conversion Kit Number Labels ● NFC-250/175H, 250/200H Orifice Identification Natural Gas Propane Gas Type 5,400- Altitude 0-5,399 ft...
  • Page 131 Attempting to alter or measure the gas valve ● outlet pressure could result in damage to the valve, causing potential severe personal injury, death or substantial property damage. Navien NFC-H boilers are shipped ready to fire natural gas ONLY. Appendixes...
  • Page 132 20052134A 20052133A 4.8/7.90 3.90/6.00 5.05/8.4 Packing <NFC-250/175H, 250/200H Orifice Identification> Gas Orifice Figure 6. Orifice Identification O-ring 8. Remove the Gas Orifice, ensure that the packing is properly seated inside the port, and then install the new Gas Orifice for use with Propane gas.
  • Page 133 WARNING CAUTION Ensure that you have turned off the power to Ensure that the High Altitude setting reflects the the boiler before accessing the DIP switches. actual location of the boiler. If not, it may cause personal injury or malfunction of the boiler. DANGER When conversion is required, be sure to ●...
  • Page 134 The DIP SW1 (Set of 6 Switches) on the circuit board c. Activate multiple zones and set the boiler to configures the operation status and model settings. operate at 1-stage MIN mode. For operation mode selection, Note refer to “11.6.7 Setting the Special Operation Modes”...
  • Page 135 Option 2. Using Digital Manometer c. Activate multiple zones and set the boiler to operate at 1-stage MIN mode (refer a. Open the offset pressure port by loosening to “11.6.7 Setting the Special Operation the screw two turns as shown in Figure 9. Modes”...
  • Page 136 13. Once the CO or offset values have been confirmed, apply the included conversion stickers to show that the appliance has been converted to Propane Gas or High Altitude. Place these labels adjacent to the rating plate as shown in Figure 11. Figure 11.

  • Page 137: Wiring Diagram

    12.2 Wiring Diagram T/S INPUT AC24V T/S INPUT AC24V T/S INPUT AC24V T/S INPUT AC24V Outdoor **Temp Sensor System Return **Temp Sensor System Supply **Temp Sensor Appendixes...

  • Page 138: Ladder Diagram

    12.3 Ladder Diagram AC INPUT(AC 120V) AC INPUT(AC 120 V) LIVE NEUTRAL LIVE NEUTRAL Terminal Board Relay 1 FILTER Recirculation Pump Relay 2 Dual Venturi Relay 6 Boiler Pump Relay 7 Relay 3 Ignitor ZONE1 Pump Relay 4 Relay 8 3-Way Valve ZONE2 Pump Relay 5...

  • Page 139: Outdoor Temperature Sensor

    When necessary, shielded cable may be used. Make sure wiring connections are secure before ● closing the cap. Navien Outdoor Temperature Sensor Kit The sensor is a water resistant appliance. ● Any damage to the appliance may require the ●...
  • Page 140 Outdoor Outdoor High MIN Low MIN °F °C Absolute High Mass Radiant Low Mass Radiant Cast Iron Baseboard Custom Radiator Finned Tube Baseboard Fan Coil Absolute °F 113 104 95 86 77 68 59 50 32 23 14 -4 -13 °C 45 40 35 30...

  • Page 141: Component Assembly Diagrams And Parts Lists

    12.6 Component Assembly Diagrams and Parts Lists 12.6.1 Case Assembly Appendixes...
  • Page 142 Description Service code Part # Remark Case Upper 20050476* Case Middle 20044456* Case Lower 20050478* Cover 30027137A 30026129* Drain Pan Adapter Lower Bracket 30026130* Heat Exchanger Bracket 20040243* Bolt (Ø4x10) 20038757* Base Bracket 20007609* Screw (Ø4x6) 20038859* PCB Lower Bracket 30022565* Screw (Ø4x8_S/W) 20044834*...
  • Page 143 12.6.2 Heat Exchanger and Waterway Assembly Appendixes...
  • Page 144 Description Service code Part # Remark Heat Exchanger Assembly 30021656A 30021564* Drain Pan Assembly 30021887A 20040239* Drain Pan Packing 30021887A 20040241* Exhaust Duct (Lower) 30019174A 20040242* Exhaust Duct Clip 30019174A 20042741* Exhaust Duct Packing (G90) 30019174A 20027350* Exhaust Duct Packing (P85) 30019174A 20042823* Exhaust Duct Adapter...
  • Page 145 12.6.3 Combustion Parts Assembly Description Service code Part # Remark Fan Assembly 30019826A 30026225* Venturi Packing 20018079* Dual Venturi 30027110A 30026308* Intake Pipe 30019120A 30019120* Screw (Ø4x10) 20034293* Orifice Packing 20022660A 20022660* 20052127A 20052127* NFB,C-175H/200H (NG) Gas Orifice 20052133A 20052133* NFB,C-175H/200H (NG,H) 20052134A 20052134*...
  • Page 146 Description Service code Part # Remark Bolt (Ø3x5) 20006365* O-ring (P34) 20019090* Gas Connector (Upper) 20051616* Screw (Ø4x12_S/W) 20043077A 20043077* O-Ring (P18) 20023434A 20023434* Fastener 20007878A 20007878* Gas Connector Adapter 20042239* O-Ring (P20) 20006934A 20006934* Gas Valve 30011586B 30011586* Gas Pipe 30025779* Gas Inlet Adapter 20042244A...
  • Page 147 12.6.4 Waterway Assembly Description Service code Part # Remark Plate Heat Exchanger 30021098B 30021098* Block Plate 20044475* Block Plate Packing 20045394* Heating Return Adapter Packing 20045397* DW filter 30014683* O-Ring (P25) 20032528* Bolt (Ø4x10) 20038757* Heating Return Adapter 20044488* O-Ring (P28) 20022142* Pump Inlet adapter 20049380*...
  • Page 148 Description Service code Part # Remark Fastener (Ø16) 20007736B 20007736* O-Ring (P16) 20006953A 20006953* Water Supply Adapter 20044486* Screw (Ø4×12) 20041461* O-Ring (P22) 20048007* Pump Inlet Adapter 20049379* Fastener (Ø36) 20017724* O-Ring (P26) 20032409* Mixing Valve Adapter 20044471* Fastener (Ø19.7) 20007733* O-Ring (P18) 20048006*...
  • Page 149 Memo...
  • Page 151 Installation Manual NFC-H Condensing Combi-Boilers Getting Service If your boiler requires service, you have several options for getting service: Contact Technical Support at 1-800-519-8794 or on the website: www.navieninc.com. ● For warranty service, always contact Technical Support first. ● Contact the technician or professional who installed your boiler. ●...

This manual is also suitable for:

Nfc-250/200h

Table of Contents