HIGH EFFICIENCY COMMERCIAL BOILERS
Lochinvar CREST Series with CONXUS Remote Connect
The Lochinvar CREST series offers high-efficiency commercial boilers with advanced features, including Modbus and BACnet MSTP protocol cascading sequencer with cascade redundancy. Available in input ranges from 750,000 to 6.0 million BTU/hr, these boilers boast up to a 25:1 turndown ratio and direct-venting capabilities up to 100 feet using various pipe materials.
RIDE THE LOCHINVAR WAVETM UP TO 6.0 MILLION BTU & 96.2% EFFICIENCY
Leveraging the exclusive Wave fire-tube design, advanced Lochinvar combustion technology, and the SMART TOUCH™ control with CONXUS, the CREST series redefines fire-tube boiler performance. Available in sizes from 750,000 to 6.0 million BTU/hr, they deliver up to 96.2% thermal efficiency.
THE CREST COMBUSTION SYSTEM
CREST boilers feature a top-mounted micro-metal fiber burner engineered for fire-tube technology. This system ensures smooth, quiet modulating combustion with up to a 25:1 turndown ratio. For example, a FBN-2001 model can modulate from its maximum 2,000,000 Btu/hr down to 80,000 Btu/hr (4% of maximum) as the heat load decreases. This modulating operation reduces fuel consumption and improves comfort by precisely matching system heat loss, minimizing on/off cycling.
REDUCE INSTALLATION COST WITH VARIABLE FLOW TECHNOLOGY
CREST boilers operate efficiently over a wide range of flow rates with minimal pressure drop. This capability supports the installation of a full flow (variable primary) system, eliminating the need for costly primary/secondary piping and pumps often required for water-tube boilers. Variable flow also enhances CREST's adaptability to frequent fluctuations in system flow rates.
HIGH EFFICIENCY WITH MINIMUM SUPPLY PRESSURE
Reliable operation is maintained with supply gas pressure as low as 4 inches water column. The Negative Regulation technology draws gas into the pre-mix combustion system, bypassing the need for utility pressure through the gas valve. This ensures steady operation even in low gas pressure environments or during peak demand. Additionally, Neg/Reg fan control optimizes the fuel/air ratio for a clean, efficient flame.
INTRODUCING BOILER PLANT CONTROL, FROM ANYWHERE.
The CREST series integrates Lochinvar's SMART TOUCH™ operating control with CONXUS advanced technology. This system offers comprehensive functionality and standard integration with Building Automation Systems via Modbus and BACnet MSTP. The CONXUS mobile communication platform enables remote monitoring and management of multiple CREST boiler plants. Users receive alerts via text or email for system status changes and can check system status or reprogram functions from any internet-capable device using the free CONXUS mobile application.
PEACE OF MIND, WHEN IT MATTERS MOST
Cascade Redundancy ensures reliable performance and minimizes downtime. If a lead boiler requires maintenance, the role automatically shifts to the next sequenced boiler. Up to eight CREST boilers can be sequenced via a simple 2-wire connection. Sequencing can be programmed for Lead-Lag or Efficiency Optimized operation:
- Lead-Lag Operation: One lead boiler modulates to meet demand. As load increases, additional lag boilers are activated sequentially. The lead role rotates daily to ensure equal runtime for each unit.
- Efficiency Optimized System: All boilers fire and modulate simultaneously at the same input rates, maximizing overall thermal efficiency.
FLEXIBLE VENTING OPTIONS
CREST boilers offer six venting configurations, allowing direct-vent air intake and exhaust runs up to 100 equivalent feet using PVC, CPVC, polypropylene, or stainless steel pipe. Multiple units can also be common-vented to reduce installation time and material costs.
Venting Options:
- Room Air Vertical
- Room Air Sidewall
- Direct-Vent
- Common-Vent*
- Direct-Vent Vertical
- Vertical w/Sidewall Air
*Contact Lochinvar for information on common venting of CREST boilers. **Available for models FB 0751-3501. Stainless steel pipe only for models FB 4001-6001.
SUPERIOR FIRE-TUBE HEAT EXCHANGER DESIGN BOOSTS THERMAL EFFICIENCY
The CREST boiler elevates fire-tube technology with its patented Wave™ configuration. This design creates turbulence in flue gas flow, maximizing energy transfer. The Wave design also enhances heat exchanger longevity by allowing tubes to flex, operating stress-free. Each fire tube is water-surrounded, and heat transfer is optimized by counterflow: water flows up, while hot flue gases flow down. This single pass effectively captures heat, reaching condensing temperatures. The combustion chamber is also water-backed for additional heat transfer.
CREST BOILER EFFICIENCY
The efficiency graph illustrates that CREST boilers maintain high thermal efficiency across various operating conditions. Efficiency remains exceptionally high (often exceeding 96%) even at low load conditions (5% efficiency) and across different water return temperatures.
CREST BOILER DIMENSIONS AND SPECIFICATIONS
| Model Number | Input MBH | Gross Output Min Max % | Net Rating MBH | Turndown | A | B | C | D | E | F | G | H | J | K | L | MNO | P | Q | R | Gas Conn. | Water Inlet/Outlet | Vent Size | Oper. Weight (with water) (lbs.) | Ship. Weight (lbs.) | |||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| FB*0751 | 50 | 750 | 96.2% | 722 | 627 | 15:1 | 78" | 30" | 55-1/2" | 57-5/8" | 66-1/8" | 11-7/8" | 11-3/8" | 11-1/4" | 12-1/2" | 55" | 51" | 13" | 8-3/4" | 26-3/4" | 23-3/4" | 49-1/2" | 7-3/8" | 1-1/4" | 3" | 6" | 6" | 1,768 | 1,560 |
| FB*1001 | 50 | 1,000 | 96.2% | 962 | 837 | 20:1 | 78" | 30" | 56-1/2" | 57-5/8" | 66-1/8" | 11-7/8" | 11-3/8" | 11-1/4" | 12-1/2" | 56" | 51" | 13" | 8-3/4" | 26-3/4" | 23-1/8" | 49-1/2" | 6-1/2" | 1-1/4" | 3" | 6" | 6" | 1,838 | 1,596 |
| FB*1251 | 63 | 1,250 | 96.2% | 1,203 | 1,046 | 20:1 | 78" | 30" | 56-1/2" | 57-3/4" | 66-1/8" | 11-7/8" | 11-3/8" | 11-1/4" | 12-1/2" | 56" | 51-3/8" | 13" | 8-3/4" | 26-3/4" | 21-5/8" | 49-1/2" | 6-1/2" | 1-1/4" | 3" | 6" | 8" | 1,975 | 1,648 |
| FB*1501 | 60 | 1,500 | 96.2% | 1,443 | 1,255 | 25:1 | 78" | 30" | 67-3/4" | 68" | 65-3/8" | 12-3/8" | 11-3/8" | 11-1/4" | 12-1/2" | 67-1/4" | 62-3/8" | 15-7/8" | 9" | 26-7/8" | 27-7/8" | 59-1/4" | 5-1/8" | 1-1/2" | 4" | 8" | 8" | 2,307 | 1,961 |
| FB*1751 | 70 | 1,750 | 96.2% | 1,684 | 1,464 | 25:1 | 78" | 30" | 66-1/4" | 68" | 65-3/8" | 12-3/8" | 11-3/8" | 11-1/4" | 12-1/2" | 65-3/4" | 61-1/2" | 15-7/8" | 9" | 27" | 27-1/8" | 58-3/4" | 5-1/8" | 1-1/2" | 4" | 8" | 8" | 2,458 | 2,017 |
| FB*2001 | 80 | 1,999 | 96.2% | 1,924 | 1,673 | 25:1 | 78" | 30" | 66-1/2" | 68" | 65-3/8" | 12-3/8" | 11-3/8" | 11-1/4" | 12-1/2" | 66" | 61-1/2" | 15-7/8" | 9" | 27" | 26-3/4" | 58-3/4" | 5-1/8" | 1-1/2" | 4" | 8" | 8" | 2,570 | 2,087 |
| FB*2501 | 125 | 2,500 | 96% | 2,400 | 2,087 | 20:1 | 77-3/4" | 35" | 83-3/4" | 83-3/4" | 63-3/4" | 13-1/2" | 11-1/4" | 10-1/2" | 12-1/4" | 83-1/4" | 76-1/4" | 19-3/4" | 9-1/4" | 28-3/4" | 32" | 71" | 7-1/4" | 2" | 4" | 8" | 9" | 3,600 | 2,577 |
| FB*3001 | 150 | 3,000 | 96% | 2,880 | 2,504 | 20:1 | 77-3/4" | 35" | 83-3/4" | 83-3/4" | 63-3/4" | 13-1/2" | 11-1/4" | 10-1/2" | 12-1/4" | 83-1/4" | 76-1/4" | 19-3/4" | 9-1/4" | 28-3/4" | 32" | 71" | 7-1/4" | 2" | 4" | 10" | 10" | 3,900 | 2,881 |
| FB*3501 | 175 | 3,500 | 96% | 3,360 | 2,921 | 20:1 | 77-3/4" | 42" | 91-1/2" | 86-3/4" | 63-1/2" | 13-1/4" | 11-1/2" | 10-3/4" | 12-1/2" | 91" | 82" | 20-1/4" | 12-3/4" | 35-1/2" | 31-3/4" | 73-1/4" | 8-3/4" | 2" | 4" | 10" | 10" | 4,600 | 3,218 |
| FB*4001 | 333 | 3,999 | 96% | 3,840 | 3,339 | 12:1 | 77-3/4" | 45-1/2" | 103-1/2" | 99" | 63-1/2" | 13-3/4" | 11-1/2" | 10-3/4" | 12-1/2" | 103" | 94" | 24-3/4" | 13-1/2" | 39-1/2" | 42-1/4" | 85-1/4" | 10-1/2" | 2-1/2" | 4" | 12" | 12" | 5,200 | 3,805 |
| FB*5001 | 500 | 4,999 | 96% | 4,800 | 4,173 | 10:1 | 77-3/4" | 46-1/2" | 102-1/4" | 99-1/2" | 63-1/2" | 15" | 11-1/2" | 10-3/4" | 12-1/2" | 101-3/4" | 92-1/2" | 22" | 14" | 39-3/4" | 39-1/2" | 84" | 9" | 2-1/2" | 6" | 12" | 14" | 5,900 | 4,101 |
| FB*6001 | 600 | 6,000 | 96% | 5,760 | 5,008 | 10:1 | 77-3/4" | 50" | 102-3/4" | 99-3/4" | 63-1/4" | 14-3/4" | 11-1/2" | 10-3/4" | 12-1/2" | 102-1/2" | 93-1/4" | 20" | 15-3/4" | 43-1/2" | 36-1/2" | 83-3/4" | 9-1/4" | 2-1/2" | 6" | 14" | 14" | 6,900 | 4,711 |
Notes: *Insert "N" for natural gas, "L" for LP gas models and "D" for dual fuel. Indoor installation only. Information subject to change without notice. Lochinvar should be consulted before selecting a boiler for installations having unusual piping and pickup requirements, such as intermittent system operation, extensive piping systems, etc. The ratings have been determined under the provisions governing forced draft burners. The Net AHRI water ratings shown are based on a piping and pickup allowance of 1.15.
SMART TOUCH™ FEATURES
- Full-Color 8" Touchscreen LCD Display
- Built-in Cascading Sequencer for up to 8 Boilers
- Built-in Redundancy
- Cascade Multiple Sized Boilers
- Lead/Lag Cascade
- Efficiency Optimized Cascade
- Front-End Loading Capability with Copper-Fin II® and Power-Fin® Boilers
- Building Management System Integration with 0-10 VDC Input
- BACnet MSTP Communications
- Modbus Communication
- Outdoor Reset Control with Outdoor Air Sensor
- Password Security
- Domestic Hot Water Prioritization (DHW tank piped with priority in the boiler loop; DHW tank piped as a zone in the system with the pumps controlled by the Smart System; DHW Modulation Limiting; Separately Adjustable SH/DHW Switching Times)
- Low Water Flow Safety Control & Indication
- Inlet & Outlet Temperature Readout
- Freeze Protection
- Service Reminder
- Time Clock Data Logging (Hours Running, Space Heating; Hours Running, Domestic Hot Water; Hours Running, Modulation Rate; Ignition Attempts; Last 10 Lockouts)
- Programmable System Efficiency Optimizers (Night Setback; Anti-Cycling; Outdoor Air Reset Curve; Ramp Delay; Boost Temperature & Time; Modulation Factor Control)
- Three Pump Control (System Pump; Boiler Pump; Domestic Hot Water Pump)
- System Pump, Boiler Pump and DHW Pump Power
SMART TOUCH™ FEATURES - TERMINAL STRIPS
- High-Voltage Terminal Strip:
- > 120 VAC / 60 Hertz / 1 Phase Power Supply (FB 0751-2001)
- > 208 VAC/ 60 Hertz/ 3 Phase Power Supply (FB 2501-3501)
- > 480 VAC/60 Hertz/ 3 Phase Power Supply (FB 4001-6001)
- Low-Voltage Terminal Strip:
- > 24 VAC Auxiliary Device Relay
- > Auxiliary Proving Switch Contacts
- > Alarm on Any Failure Contacts
- > Runtime Contacts
- > DHW Thermostat Contacts
- > Unit Enable/Disable Contacts
- > System Sensor Contacts
- > DHW Tank Sensor Contacts
- > Outdoor Air Sensor Contacts
- > Cascade Contacts
- > 0-10 VDC BMS External Control Contact
- > 0-10 VDC Variable Speed Boiler Pump Control Contact
STANDARD FEATURES
- Up to 96.2% Thermal Efficiency
- Proof of Closure Valve (6001)
- Modulating Burner with up to 25:1 Turndown
- Direct-Spark Ignition
- Low NOx Operation
- Sealed Combustion Air Inlet Filter w/Replacement Reminder
- Low Gas Pressure Operation
- Vertical and Horizontal Direct Venting:
- > Direct Vent up to 100 Feet
- > PVC, CPVC, Polypropylene or AL29-4C (FB 0751-3501)
- > AL29-4C (FB 0751-6001)
- ASME "H" Stamped Heat Exchanger
- 316L Stainless Steel Fire Tubes
- 160 psi Working Pressure
- On/Off Switch
- Adjustable High Limit with Manual Reset
- Low Water Cutoff with Manual Reset & Test
- High & Low Gas Pressure Switches w/Manual Reset
- Low Air Pressure Switches
- Condensate Trap w/Blocked Drain Switch
- Drain Valve
- System Sensor
- Outdoor Air Sensor
- Inlet & Outlet Temperature Sensors
- High-Voltage Terminal Strip
- Low-Voltage Terminal Strip
- Downstream Gas Test Cocks
- 50 psi ASME Relief Valve
- Temperature & Pressure Gauge
- Zero Clearances to Combustible Materials
- High Altitude Models Available
- 10-Year Limited Warranty (See Warranty for Details)
- 1-Year Warranty on Parts (See Warranty for Details)
CODES & REGISTRATIONS
- ASME Certified, "H" Stamp / National Board
- California Code Compliant
- CSD1 / Factory Mutual / GE Gap Compliant
- Canadian Registration Number (CRN)
- South Coast Air Quality Management District Qualified (FB 0751-2001)
OPTIONAL EQUIPMENT
- Alarm Bell
- BMS Gateway - BACnet IP or LonWorks
- Wireless Outdoor Temperature Sensor
- Condensate Neutralization Kit
- Common Vent Kits
- Damper Motorized Isolation Valve
- Variable Speed Boiler Pump
- Electrical Options (Shipped Loose):
- FB 0751-2001 > 208V/1¡/60Hz / 120V/1¡/60Hz
- > 480V/1¡/60Hz / 120V/1¡/60Hz
- > 600V/1¡/60Hz / 120V/1¡/60Hz
- FB 2501-3501 > 480V/3¡/60Hz / 208V/3¡/60Hz
- > 600V/3¡/60Hz / 208V/3¡/60Hz
- FB 4001-6001 > 600V/3¡/60Hz / 480V/3¡/60Hz
CONTACT INFORMATION
Lochinvar, LLC
300 Maddox Simpson Parkway
Lebanon, Tennessee 37090
P: 615.889.8900 | F: 615.547.1000
Lochinvar.com
Document: FBNT-04 TEMP (Replaces FBNT-03 2/18). © Lochinvar, LLC - ASB - 5M 2/18 - Printed in U.S.A.
