CWL-LE Series – Compact Design

Standing 29.5″ high, the compact size and zero-clearance allow the CWL to be installed safely and easily in areas not approved for other boilers.

The CWL’s round design allows water to circulate completely around the combustion area with the exception of the base, getting the maximum heat exchange.  This unique wet-wall unit is designed without a refractory combustion chamber.

  • FIRING RATE 0.85 to 0.90GPH – Allows the installer to size the boiler more closely to the home heating needs for greater efficiency. The lowest firing rate, 0.85-89,000 BTU, is necessary for many well insulated homes where the heat loss is minimal.
  • COMBUSTION CHAMBER – area circumference is surrounded by water, assures quieter operation while efficiently transferring maximum heat to your home and safe for installation even in zero-clearance areas
  • PUMP PRESSURE – The CWL operates at 140 PSI pump pressure for better fuel atomization, thereby having the ability to tolerate fuel oil with heavy ends.
  • IGNITION SYSTEM – The CWL Series is standard with a state-of-the-art, solid state ignition system, making it more tolerant to low voltage or voltage fluctuations.
  • ELECTRONIC DELAY with Solenoid Valve “clean-cut” Fuel Pump.
  • WATER CONTENT – Compared to other wet leg boilers, the CWL-Series has exceptional water content. The first size has 15 gallons of water. High water volume and placement of the coil in the hottest part of the boiler allows for maximum coil performance.
  • EFFICIENCIES UP TO 86.2% AFUE – The unique combustion design of the CWL boiler heat exchanger, surrounded by water, assures quieter operation while efficiently transferring maximum heat to your home.
  • STANDARD FEATURES- The following built-in features found in all Thermo-Dynamics boilers increase the longevity of the boiler and make the unit easier to service, ensuring maximum efficiency and performance for the life of the boiler.
  • BUILT-IN “AIR SCOOP” – purges air from the system providing a quiet, trouble free hot water heating system without the use of external devices.
  • EXTENDED FLANGE COIL – is away from the boiler for easy accessibility. The use of ribbed neck carriage bolts eliminates the problems encountered when a weld stud is broken during servicing. The large coil plate allows for a greater gasket sealing area.
  • EASY CLEANING – and maintenance accessibility to combustion areas and the open tubes make it easy for the service technician to thoroughly clean the boiler. No tight, pin-type passage ways with “hidden nooks and crannies”, making a thorough cleaning impossible. A well-maintained boiler continues to perform at higher efficiency and is less likely to develop service problems.

Standard Features

  • TOP FLUE CONNECTION – Makes installation easy and simplifies annual servicing.
  • OVAL TUBE DESIGN – Makes possible the most efficient utilization of fuel, production of central heat and domestic hot water with the most economical transfer of energy.
  • COPPER DOMESTIC HOT WATER COIL – Provides the hot water you need when it is needed. The cost of a separate domestic hot water system is eliminated
  • ASME CONSTRUCTION – Designed, constructed and hydrostatically tested in accordance with the American Society of Mechanical Engineers Boiler Code Section IV.

ASME Code BoilerGeniSys Control (Beckett)
Built-In-Air-TrapAquasmart Control or Hydrolevel Control
Flush Jacket007 or Equivalent Circulator (mounted)
InsulationBrass Boiler Drain Valve
Altitude, Temperature & Pressure GaugeUnit Shipped Completely Assembled and Packaged
ASME Relief ValveApproved for Combustible Flooring
5 GPM Tankless HeaterNational Board Stamped
Solid State Ignition TransformerOil Vent Damper Included
Optional Equipment
Rear Flue Kit with Built-In Draft RegulatorDV Model - Direct Vent
Less Coil Option Available


All appliance designs are forced draft pressure fired for optimum performance. They are available with either Beckett, Carlin, or Riello oil burner.

Heating Capacity103,000108,000
Net Rating BTU/HR89,00094,000
Firing Rate0.850.90
Chimney Size8 x 8 x 158 x 8 x 15
Over Fire Pressure WC0 - +0.050 - +0.08
Water Content15 GAL15 GAL
Coil Capacity5 GAL5 GAL
Jacket Height*29 ½"29 ½"
Jacket Width21"21"
Coil Supply Height22"22"
Supply Height (Hydronic)27 ½"27 ½"
Burner Height7 ⅞"7 ⅞"
HydronicReturn Height15 ½"15 ½"
Flue Pipe Diameter5"5"
Washout (Alt Return Height)3 ½"3 ½"
Jacket Depth (including flange)22"22"
Depth Front to Rear w/Burner30 ¾"30 ¾"
Hydronic Supply1 ¼"1 ¼"
Hydronic Return Size1 ¼"1 ¼"
Washout (Alt Return)1 ¼" (2)1 ¼" (2)
AFUE Rating86.286.0
*Specifications apply to CWL, NCWL and CWL-DV except when using REAR FLUE KIT, jacket height increases by 4 ¼ inches.

CWL – Series Manual

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Boiler Warranty

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