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T-H3S-OS-LP 180,000 BTU Condensing Outdoor Tankless Water Heater

T-H3S-OS-LP 180,000 BTU Condensing Outdoor Tankless Water Heater

T-H3S-OS-LP 180,000 BTU Condensing Outdoor Tankless Water Heater
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T-H3S-OS-LP  or T-H3S-P (Outdoor Propane 180,000 BTU High Efficiency Ultra-Low NOx Condensing Tankless Water Heater )
The T-H3S-OS-LP outdoor tankless on demand water heater is well suited for residential 2 - 3 bathroom homes and commercial applications such as small restaurants and beauty salons. Complies with Ultra-Low NOx regulations. Utilizing commerical grade copper alloy for the heat exchanger tubing, the T-H3S-OS-LP is also suitable for heavier residential usages such as space heating or domestic recirculation systems. Remote control included as a standard feature on Outdoor models. 
Number of showers this unit can handle, depending on ground water temperature.

Warmer Climates 

Cooler Climates 


The T-H3S-OS-LP outdoor propane tankless water heater 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.

The T-H3S instant and endless hot on-demand tankless water heating system is a high efficient, condensing, tankless water heater perfect for residential applications. The T-H3S-OS-LP outdoor propane tankless water heater can produce enough hot water for three bathrooms in warmer climates or two baths in colder climates.
  • ENERGY STAR® qualified
  • For 3 bathrooms in warmer climates or 2 baths in colder climates
  • Primary heat exchanger utilizes commercial-grade copper alloy for 25 times better heat transfer than stainless steel
  • Secondary heat exchanger utilizes 316L stainless steel for better corrosion resistance
  • NSF certified for commercial applications
  • Complies with Ultra-Low NOx regulations of less than 14 ng/J (<20ppm)
  • Includes remote control as standard feature
  • Safety features include freeze, overheat, surge protection, and troubleshooting diagnostic codes
  • 15-year limited heat exchanger, 5 yrs limited parts Residential use

Tech Specs

Emissions: Ultra Low NOx
Maximum BTUs: 180,000
Minimum BTUs: 19,500
Water Connection Location: Bottom
Water Connection: 3/4"
Flow Rate: 8.00
Heat Exchanger: Copper & Stainless
Voltage: AC 120V
UEF: 0.94
ENERGY STAR® Qualified: Yes
LEED Rating: 1.5
Remote Control: Yes
Technology: Condensing
Multilink: No

Dimensions & Venting

Height: 22.50"
Width: 17.75"
Depth: 10.75"
Product Weight: 69 lbs.
Vent Type: NA
Vent Size: NA