Lochinvar Crest 751 Installation & Operation Manual
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Lochinvar Crest 751 Installation & Operation Manual

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FBII-I-O Rev A
Installation & Operation Manual
Models: 751 - 1251
This manual must only be used by
WARNING
a qualified heating installer / service
technician. Read all instructions,
including this manual and the Crest
Service Manual, before installing.
Perform steps in the order given.
Failure to comply could result in
severe personal injury, death, or
substantial property damage.
Save this manual for future reference.

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  • Page 1 FBII-I-O Rev A Installation & Operation Manual Models: 751 - 1251 This manual must only be used by WARNING a qualified heating installer / service technician. Read all instructions, including this manual and the Crest Service Manual, before installing. Perform steps in the order given. Failure to comply could result in severe personal injury, death, or substantial property damage.

  • Page 2: Table Of Contents

    Contents HAZARD DEFINITIONS ............ 2 Termination and Fittings ..........25 PLEASE READ BEFORE PROCEEDING ......3 Multiple Vent/Air Terminations ....... 25-26 THE CREST -- HOW IT WORKS ........4-5 Room Air ..............26 RATINGS ................6 5. HYDRONIC PIPING System Water Piping Methods ......... 27 1.

  • Page 3: Please Read Before Proceeding

    Installation & Operation Manual Please read before proceeding Installer – Read all instructions, including The California Safe Drinking Water and WARNING WARNING this manual and the Crest Service Manual, Toxic Enforcement Act requires the before installing. Perform steps in the Governor of California to publish a list of order given.

  • Page 4: The Crest - How It Works

    Installation & Operation Manual The Crest - How it works... 20. Ignition electrode Front access panels An electrical spark across the electrodes will ignite the burner. Provides access to the controls compartment. 21. Line voltage junction box Top access panel The line voltage junction box contains the connection points for Provides access to the burner compartment.
  • Page 5 Installation & Operation Manual The Crest - How it works... (continued) IMG01128 IMG01025 Front View Rear View IMG01130 IMG01129 Left Side (inside unit) Right Side (inside unit)

  • Page 6: Ratings

    Installation & Operation Manual Ratings Crest Other Specifications AHRI Rating Vent Weight AHRI Model Number Gross Input Appliance Size w/Water Pipe Pipe Ratings Output Water Gas Inlet (lbs.) Size Size Size Water, Content Size Outlet Inlet Note: Change “N” to (Notes 4 - 6) Gallons “L”...

  • Page 7: Determine Boiler Location

    Installation & Operation Manual Determine boiler location Installation must comply with: Check around the boiler for any potential air contaminants • Local, state, provincial, and national codes, laws, that could risk corrosion to the boiler or the boiler combustion regulations, and ordinances. air supply (see Table 1A on page 9).

  • Page 8: Provide Air Openings To Room

    Installation & Operation Manual Determine boiler location Flooring and foundation If you do not provide the recommended NOTICE service clearances shown, it may not be Flooring possible to service the boiler without removing it from the space. The Crest is approved for installation on combustible flooring, but must never be installed on carpeting.

  • Page 9: Using An Existing Vent System To Install A New Boiler

    Installation & Operation Manual Determine boiler location (continued) When using an existing vent system to install a new boiler: Table 1A Corrosive Contaminants and Sources Products to avoid: Failure to follow all instructions can result WARNING in flue gas spillage and carbon monoxide Spray cans containing chloro/fluorocarbons emissions, causing severe personal injury Permanent wave solutions...

  • Page 10: Removing A Boiler From Existing Common Vent

    Installation & Operation Manual Determine boiler location When removing a boiler from existing common vent system: Do not install the Crest into a common d. Place in operation the appliance being inspected. DANGER vent with any other appliance except Follow the lighting instructions. Adjust thermostat so as noted in Section 2 on page 18.

  • Page 11: Remove Boiler From Wood Pallet

    Installation & Operation Manual Determine boiler location (continued) Remove boiler from wood pallet Figure 1-3 Boiler Removed from Shipping Pallet After removing the outer shipping crate and plastic from the boiler, remove the parts package (packaged parts inside the controls compartment of the boiler inside the lower front access panel).

  • Page 12: Combustion And Ventilation Air Requirements

    Installation & Operation Manual Determine boiler location Combustion ventilation requirements for appliances drawing air from the equipment room Provisions for combustion and ventilation air must be in accordance with Air for Combustion and Ventilation, of the latest edition of the National Fuel Gas Code, NFPA 54 / ANSI Z223.1, in Canada, the latest edition of CGA Standard B149 Installation Code for Gas Burning Appliances and Equipment, or applicable provisions of the local building codes.
  • Page 13 Installation & Operation Manual Determine boiler location (continued) Under no circumstances should the If a single combustion air opening is provided to bring CAUTION equipment room ever be under negative combustion air in directly from the outdoors, the pressure. Particular care should be taken opening must be sized based on a minimum free area where exhaust fans, attic fans, clothes dryers, of one square inch per 3000 Btu/hr (7 cm...

  • Page 14: General Venting

    Installation & Operation Manual General venting Direct venting IMG01057 IMG01033 IMG01056 Sidewall Vertical Vent, Sidewall Air Vertical Optional room air IMG01059 IMG01058 Vertical Sidewall...

  • Page 15: Install Vent And Combustion Air Piping

    Installation & Operation Manual General venting (continued) Install vent and combustion air piping The Crest must be vented and supplied Sealing of Type “B” double-wall vent material or galvanized DANGER with combustion and ventilation air as vent pipe material used for air inlet piping on a sidewall or described in this section.

  • Page 16: Vent And Air Piping

    Installation & Operation Manual General venting Air intake/vent connections When a sidewall or vertical rooftop combustion air supply system is disconnected for any reason, the air inlet pipe must Combustion Air Intake Connector (FIG. 2-1) - Used to be resealed to ensure that combustion air will be free of provide combustion air directly to the unit from outdoors.

  • Page 17: Min./Max. Combustion Air & Vent Piping Lengths

    Installation & Operation Manual General venting (continued) Table 2B Direct Vent Minimum / Maximum Allowable Air / Vent Lengths AIR INLET VENT Input Model De-Rate per Air Intake Air Intake Air Intake Vent Vent Vent 25 feet of Vent Diameter Min.

  • Page 18: Common Venting

    DRH30007 of the same size. FB1251 8" DRH30001 Each Crest boiler must have a Lochinvar supplied flue damper installed (see Table 2D). PVC/CPVC This product has been approved for use with the PVC/CPVC Only vertical direct vent, positive pressure, Category vent materials listed in Table 2E on page 19.
  • Page 19 Installation & Operation Manual General venting (continued) Table 2E PVC/CPVC Vent Pipe, and Fittings Dry fit vent or air piping to ensure proper fit up before assembling any joint. The pipe should go Approved PVC/CPVC Vent Pipe and Fittings a third to two-thirds into the fitting to ensure Item Material Standard...

  • Page 20: Polypropylene

    Installation & Operation Manual General venting Polypropylene Installation of a polypropylene vent system NOTICE should adhere to the vent manufacturer’s This product has been approved for use with polypropylene installation instructions supplied with the vent with the manufacturers listed in Table 2F. vent system.

  • Page 21: Vertical Direct Venting

    Installation & Operation Manual Vertical direct venting Vent/air termination – vertical Follow instructions below when determining Figure 3-2 Vertical Termination of Air and Vent w/Rain WARNING vent location to avoid possibility of severe personal injury, death or substantial property damage. Do not connect any other appliance to the WARNING vent pipe or multiple boilers to a common...

  • Page 22: Multiple Vent/Air Terminations

    Installation & Operation Manual Vertical direct venting 3. The vent piping must terminate in an up-turned coupling Figure 3-4 Alternate Vertical Terminations with Multiple as shown in FIG. 3-1. The top of the coupling or the Boilers rain cap must be at least 36" (914 mm) above the air intake.

  • Page 23: Determine Location

    Installation & Operation Manual Sidewall direct venting Vent/air termination – sidewall Follow instructions below when Sidewall vent and air inlet terminations WARNING WARNING determining vent location to avoid must terminate in the same pressure possibility of severe personal injury, death, zone.

  • Page 24: Sidewall Direct Venting Vent/Air Termination - Sidewall

    Installation & Operation Manual Sidewall direct venting Vent/air termination – sidewall Figure 4-2A PVC/CPVC/ Polypropylene Sidewall Termination Models 751 - 1001 w/Field Supplied Fittings Figure 4-1B PVC/CPVC/ Polypropylene Sidewall Termination of Air and Vent w/Field Supplied Fittings BIRD SCREEN TO BOILER INTAKE AIR CONNECTION 12"...

  • Page 25: Prepare Wall Penetrations

    Installation & Operation Manual Sidewall direct venting (continued) Vent/air termination – sidewall Prepare wall penetrations 8. Locate terminations so they are not likely to be damaged by foreign objects, such as stones or balls, or subject to buildup Air pipe penetration: of leaves or sediment.

  • Page 26: Room Air

    Installation & Operation Manual Sidewall direct venting 2. Place wall penetrations to obtain minimum clearance Figure 4-7 Room Air (Direct Exhaust Terminations) of 12 inches (305 mm) between vent pipe and adjacent air inlet, as shown in FIG. 4-5 for U.S. installations. For ROOM AIR (DIRECT EXHAUST TERMINATIONS) Canadian installations, provide clearances required by Vent Termination...

  • Page 27: Hydronic Piping

    Installation & Operation Manual Hydronic piping System water piping methods General piping information The Crest is designed to function in a closed loop pressurized Basic steps are listed below along with illustrations on the system not less than 12 psi (83 kPa). A temperature and following pages, which will guide you through the installation pressure gauge is included to monitor system pressure and of the Crest (5-2 thru 5-5).

  • Page 28: Circulator Sizing

    Installation & Operation Manual Hydronic piping Circulator sizing The Crest heat exchanger does have a pressure drop, which must be considered in your system design. Refer to the graph in FIG. 5-1 for pressure drop through the Crest heat exchanger. Figure 5-1 Pressure Drop vs.

  • Page 29: Near Boiler Piping Components

    Factory supplied. The pressure relief valve is sized to FB(N,L)1001 ASME specifications. FB(N,L)1251 9. System temperature sensor: Lochinvar supplies a system temperature sensor. The sensor is to be installed in the heating loop downstream from the boiler hot water piping and heating loop junction. The sensor should be located far enough downstream to sense system diluted water temperature.
  • Page 30 Installation & Operation Manual Hydronic piping Figure 5-2 Single Boiler - Recommended - Primary / Secondary Piping with a Hot Water Generator FROM SYSTEM SYSTEM RETURN SENSOR HOT WATER GENERATOR 12" BALL VALVE (TYPICAL) RELIEF AIR SEPERATOR VALVE DRAIN PORT (TYPICAL) SYSTEM SUPPLY SENSOR...
  • Page 31 Installation & Operation Manual Hydronic piping (continued) Table 5C Multiple Boilers - Common Header - Primary / Secondary Flow Number of Units Model Recommended Common Header Pipe Sizes in Inches FB 0751 FB 1001 FB 1251 [Based on a boiler ΔT of 30°F.] A system supply sensor (factory supplied) MUST BE installed for proper boiler operation.
  • Page 32 Installation & Operation Manual Hydronic piping Figure 5-4 Single Boiler - Alternate - Fixed or Variable Flow Primary System Piping RELIEF VALVE BALL VALVE (TYPICAL) FROM SYSTEM AIR SEPERATOR BOILER DRAIN DRAIN PORT (TYPICAL) Y-STRAINER (RECOMMENDED) SYSTEM CIRCULATOR PRESSURE REDUCING VALVE (OPTIONAL) BYPASS EXPANSION...
  • Page 33 Installation & Operation Manual Hydronic piping (continued) Figure 5-5 Multiple Boilers - Alternate - Common Header - Fixed or Variable Flow Primary RELIEF VALVE (TYPICAL) ISOLATION VALVE 2-WAY MOTORIZED VALVE (OPTIONAL) FROM SYSTEM BOILER DRAIN (TYPICAL) AIR SEPERATOR DRAIN PORT SYSTEM RETURN (TYPICAL) SENSOR...

  • Page 34: Gas Connections

    Installation & Operation Manual Gas connections Connecting gas supply piping 3. Purge all air from the gas supply piping. For dual fuel models, reference the Crest NOTICE Dual Fuel Supplemental Manual. 4. Before placing the boiler in operation, check the boiler and its gas connection for leaks.

  • Page 35: Natural Gas

    Installation & Operation Manual Gas connections (continued) Natural gas supply pressure requirements Use two wrenches when tightening gas WARNING piping at boiler (FIG. 6-2), using one 1. Pressure required at the gas valve inlet pressure port: wrench to prevent the boiler gas line •...

  • Page 36: Check Inlet Gas Supply

    Installation & Operation Manual Gas connections Table 6B Natural Gas Pipe Size Chart TABLE - 6B Capacity of Schedule 40 Metallic Pipe in Cubic Feet of Natural Gas Per Hour (based on .60 specific gravity, 0.30" w.c. pressure drop) Length of Pipe in Straight Feet Pipe Size (Inches)

  • Page 37: Gas Pressure

    Installation & Operation Manual Gas connections (continued) Gas Pressure Do not check for gas leaks with an open WARNING flame -- use the bubble test. Failure to The gas pressure must remain between 4 inches w.c. use the bubble test or check for gas leaks (.99 kPa) minimum and 14 inches w.c.

  • Page 38: Field Wiring

    Installation & Operation Manual Field wiring Line voltage connections ELECTRICAL SHOCK HAZARD – For WARNING your safety, turn off electrical power supply 1. Connect 120 VAC power wiring to the line voltage terminal before making any electrical connections strip in the junction box, as shown in FIG. 7-1. to avoid possible electric shock hazard.

  • Page 39: Low Voltage Connections

    Installation & Operation Manual Field wiring ModBus / BACnet (continued) Low voltage connections The RS-485 ModBus / BACnet cable is connected to the ModBus terminals. Use shielded, 2-wire twisted pair cable. If 1. Route all low voltage wires through the knockouts in the desired, the shield can be connected to ground by installing a rear of the boiler, as shown in FIG.

  • Page 40: Wiring Of The Cascade

    Installation & Operation Manual Field wiring Auxiliary switch 1 & 2 Wiring of the cascade When wiring the boilers for Cascade operation, select one boiler Additional field supplied limit controls may be connected to as the Leader boiler. The remaining boilers will be designated the auxiliary switch inputs.
  • Page 41 Installation & Operation Manual Field wiring (continued) Figure 7-3 Low Voltage Field Wiring Connections...

  • Page 42: Condensate Disposal

    Installation & Operation Manual Condensate disposal Condensate drain 9. Do not expose condensate line to freezing temperatures. 1. The Crest is a high efficiency appliance that produces condensate. Use materials approved by the authority NOTICE 2. The rear of the boiler has a 1 inch (25.4 mm) stainless steel having jurisdiction.

  • Page 43: Startup

    Installation & Operation Manual Start-up Check/control water chemistry Fill and test water system Do not use petroleum-based cleaning or CAUTION sealing compounds in the boiler system. 1. Fill system only after ensuring the water meets the Damage to elastomer seals and gaskets requirements of this manual.

  • Page 44: Check For Gas Leaks

    Installation & Operation Manual Start-up Check for gas leaks Propane boilers only – Your propane WARNING supplier mixes an odorant with the propane Before starting the boiler, and during to make its presence detectable. In some WARNING initial operation, smell near the floor and instances, the odorant can fade, and the around the boiler for gas odorant or any gas may no longer have an odor.

  • Page 45: Start The Boiler

    Installation & Operation Manual Start-up (continued) Final checks before starting the boiler  Check vent piping and air piping 1. Check for gastight seal at every connection, seam of air  Read the Crest Service Manual to familiarize yourself piping, and vent piping. with SMART TOUCH control module operation.

  • Page 46: For Your Safety Read Before Operating

    Installation & Operation Manual Start-up Figure 9-2 Operating Instructions 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 47 Installation & Operation Manual Start-up (continued) Check flame and combustion Set space heating operation (continued) 4. Navigate to the Service Screen from the Home Screen by Verify space heat circulator mode pressing the MAIN MENU button and then the SERVICE button.
  • Page 48 Installation & Operation Manual Start-up Set Hot Water Generator (HWG) operation To set the date, highlight Date using the arrows and press the SELECT button. Use the left and right arrows Verify HWG mode to select the day of the week and the up and down There are two (2) modes of operation for HWG.

  • Page 49: Operating Information General

    Installation & Operation Manual Operating information General HWG priority The SMART TOUCH control allows the connection of a HWG How the boiler operates thermostat or tank sensor to the low voltage connection board. When a tank sensor is connected, the HWG thermostat input The Crest uses an advanced stainless steel heat exchanger is ignored.
  • Page 50 Installation & Operation Manual Operating information Gradient limiting Ramp Delay For systems with lower flow, the SMART TOUCH can limit If during operation of the boiler the outlet water temperature the firing rate (when enabled) when a space heating call for is rising too quickly, the control will reduce the firing rate to heat starts, or when switching from a DHW call for heat to a its lowest setting.
  • Page 51 Installation & Operation Manual Operating information (continued) Monitor external limits High limit operations Connections are provided on the connection board for The Crest SMART TOUCH control has two (2) integral limits, external limits such as an additional high limit. one auto reset and one manual reset. The Crest also has one SMART TOUCH control will shut off the burner and auxiliary manual reset high limit.

  • Page 52: Cascade

    Installation & Operation Manual Operating information Cascade Sequence of the cascade When multiple boilers are installed, they can be wired together To equalize the run time of all boilers on the Cascade, the in a cascade sequence. A maximum of eight boilers can be firing sequence will automatically be changed at set intervals.

  • Page 53: Sequence Of Operation

    Installation & Operation Manual Operating information (continued) Sequence of operation Upon a call for heat, the control turns on the appropriate pumps (system and boiler pumps for a space heating call, HWG pump for a hot water generator call). The control confirms that the low water cutoff contacts are closed and energizes the louvers (optional) and damper (optional) relays.

  • Page 54: Home Screen

    Installation & Operation Manual Operating information Crest control module The Home Screen displays status, modulation rate, outlet water temperature, inlet water temperature, flue temperature, system supply temperature, system return temperature, outdoor air temperature, and domestic hot water tank temperature. The boiler can be started and stopped by pressing the ON/OFF button. The Boiler Status Screen and Main Menu Screen can be accessed by pressing the appropriate button.

  • Page 55: Main Screen

    Installation & Operation Manual Operating information (continued) Use the Main Menu Screen (FIG. 10-2) to access the screens necessary to set temperatures, operating conditions, and monitor boiler operation. The Crest is equipped with a SMART TOUCH control system. All menu options are accessed by touching the screen with your finger or a stylus from a PDA.

  • Page 56: Maintenance

    Installation & Operation Manual Maintenance Maintenance and annual startup Table 11A Service and Maintenance Schedules Owner maintenance Service technician (see the Crest User’s Information Manual for (see the following pages for instructions) instructions) General: • Address reported problems, if any •...
  • Page 57 Installation & Operation Manual Maintenance (continued) Follow the service and maintenance procedures given throughout this manual and in component literature WARNING shipped with the boiler. Failure to perform the service and maintenance could result in damage to the boiler or system. Failure to follow the directions in this manual and component literature could result in severe personal injury, death, or substantial property damage.
  • Page 58 Installation & Operation Manual Maintenance Check expansion tank 2. After following the above warning directions, if the relief valve weeps or will not seat properly, replace the relief 1. Expansion tanks provide space for water to move in valve. Ensure that the reason for relief valve weeping is and out as the heating system water expands due to the valve and not over-pressurization of the system due temperature increase or contracts as the water cools.

  • Page 59: Check Burner Flame

    NOTE: Be sure to pay close 3. Allow time for the boiler to cool to room temperature if attention to the Lochinvar logo. Align the logo with the Lochinvar it has been firing. GAS/AIR MANIFOLD COVER logo on the gas/air manifold to 4.
  • Page 60 Installation & Operation Manual Maintenance Review with owner 15. Replace the burner mounting plate assembly and gas/air 1. Review the Crest User’s Information Manual with the manifold assembly. Ensure gaskets are in good condition owner. and positioned properly. Restore boiler to operation. 2.

  • Page 61: Diagrams

    Installation & Operation Manual Diagrams Figure 12-1 Ladder Diagram...

  • Page 62: Wiring Diagram

    Installation & Operation Manual Diagrams Figure 12-2 Wiring Diagram BOX DEPICTS OPTIONAL ITEMS BOX DEPICTS DUAL SENSOR SINGLE HOUSING MODBUS BOARD X1-1 LARGE CONNECTION BOARD X1-2 LOW VOLTAGE X1-3 120 VAC CN6-3 X6-3 SHIELD INTEGRATED CONTROL CN6-2 X6-1 MODBUS HIGH VOLTAGE OPTION CN6-1 X6-2...
  • Page 63 NOTES...

  • Page 64: Revision Notes

    Revision Notes: Revision A (ECO #C17106) initial release. FBII-I-O Rev A 01/15...

This manual is also suitable for:

Crest 1251

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