The Olsen OLSSC features 95% AFUE.

-Built-In Primary/Secondary Piping
-Built-In Low Water Cut Off
-5:1 Turn Down Ratio
-Approved for PVC, CPVC and Polypropylene venting
-Original Heat Exchanger
-Low Maintenance, Self-Cleaning
-Designed in North America, for North America
-150 psi MAWP


-Wall Mounted: Bracket included.
-Boiler Control Module: Automatic Line Voltage/Intermittent Direct Spark Ignition/Modulating with a 5:1 combustion turn down ratio. For multiple boiler applications – the control module can stage up to 16 boilers.
-User Display Interface: Easy programming with text display. Outdoor Temperature Sensor included.
-Heat Exchanger: High grade 316L/444 Stainless Steel Fin Coil with Flame Sight Glass.
-Built-in Primary/Secondary Manifold Piping and Pump.
-Combustion: Gas Valve with Premix Venturi and Blower, Durable Stainless Steel Mesh Modulating Burner with 5:1 turn down ratio, Direct Spark Igniter, Flame Sensor and LP Conversion Kit included.
-Electrical: Detachable Low Voltage Terminal Strip, High Voltage Junction Box and Transformer.
-Other: Factory installed probe-type Low Water Cut Off with test feature, 30 PSI Safety Relief Valve, Boiler Drain Valve and Condensate Drain with built in trap.