The compact T-K4 is a fully modulating, gas fired, tankless water heater perfect for residential applications. With gas inputs of 190,000 BTU, the T-K4 can produce enough hot water for up to three bathrooms in warmer climates.


Download T-K4-IN/OS Manual

Download T-K4-IN Specification Sheet

Download T-K4-OS Specification Sheet 


Available for indoor and outdoor installation, the T-K4 supplies hot water to domestic hot water systems (directly or indirectly) which can be used with storage tanks, recirculation systems, hydronic heating systems, radiant floor systems, and/or domestic & heating applications.

  • Maximum flow rate of 8.0 GPM at 35°F temperature rise (4.4 GPM at 70°F rise)

  • Energy Factor of 0.82 for NG and LPG

  • ENERGY STAR® qualified

  • Indoor model includes both a remote control and power cord as standard features

  • Outdoor model includes remote control as standard feature

  • Venting with Category III stainless steel

  • Safety features include freeze, overheat, surge protection, and troubleshooting diagnostic codes

Natural Gas Input  Min. 11,000 Btu   Max. 190,000 Btu 
LPG Input  Min. 11,000 Btu   Max. 190,000 Btu  
Gas Connection  3/4" NPT    
Water Connection  3/4" NPT    
Natural Gas Pressure Inlet  Min. 5.0" W.C.  Max. 10.5" W.C. 
LP Gas Pressure Inlet  Min. 8.0" W.C.  Max. 14.0" W.C.  
Weight  38 lbs   
Dimensions  20.5" x 13.8" x 8.5"    
Ignition  Electronic Ignition    
Electrical Supply  AC 120V (60 Hz)   
Water Pressure  Min. 15 psi   Max. 150 psi  
Natural Manifold Pressure 2.0-2.5" W.C.   
LP Manifold Pressure 3.7-4.0" W.C.    
Sidewall Vent Terminator (Hood) and Wall Thimble (4”-7”)
Sidewall Vent Terminator (Hood) and Wall Thimble (4”-7”)
Backflow Preventer & F-F Adaptor
Backflow Preventer & F-F Adaptor
Recess Box
The 9007674005 completely houses the tankless hot water unit and allows it to be completely recessed into a wall for a smooth, almost seamless look. It is just over 14 inches wide so it easily fits in-between the studs.
Pipe Cover
The 9007671005 Pipe cover is designed to be attached directly to the bottom side of the unit to provide a cover for the pipe connection entry.
Direct Vent Conversion Kit
Direct Vent Conversion Kit
Temperature Remote Controller
The 9007666005 Temperature Remote Controller allows the output temperature to be adjusted beyond the factory settings, and works as a diagnostic tool for error codes.
Isolation Valves & Pressure Relief Valve
Isolation valves are used to isolate a unit for service. The Pressure Relief Valve is to help protect the unit and release if the pressure in the tankless water heater or hot water system exceeds 150 psi.