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Triangle Tube Keystone - 399,000 BTU - Tankless Water Heater - NG - 11 GPM - 96.3% Thermal Efficiency
Model:
KW 399
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Features
Fuel
Natural Gas
Location
Indoor
# of Showers
0.0
- (1) Triangle Tube KW 399 Tankless Water Heater
- (1) Outdoor Reset Sensor
- (1) Natural Gas to Liquid Propane Conversion Kit
Triangle Tube is best known for two things: feats of hydronic innovation and incredibly efficient products. If you are looking for those qualities in your water heater, the Keystone certainly fits the bill. The Keystone tankless water heater is a high-efficiency, condensing water heater for large spaces. The condensing technology behind the Keystone will capture and reuse gaseous heat that escapes traditional water heaters. Stainless steel construction of the heat exchanger and an internal condensate trap will protect the KW 399 from corrosion. The Keystone's modulating burner scales heat production based on your needs and reduces unnecessary energy consumption. All told, the Keystone is an incredibly reliable and efficient water heating solution.
Product Features
Pre-Mix Burner
The pre-mix burner on Keystone water heaters means that your water heating will be environmentally friendly and clean. Pre-mixing the fuel improves air quality and reduces NOx output to less than ten parts per million, well within the strictest low NOx guidelines.
Easy Setup
Keystone water heaters include several features that streamline the installation process. A large, easy-to-use display and consolidated connections at the top of the unit make setting up a Keystone quick and simple.
Communicating
Up to eight Keystone units may be staged together through the Keystone's controls. This allows you to expand your water heating to accommodate the largest of applications without sacrificing efficiency. The Keystone's controls also support integration into building automation systems.
PID Staging
The Keystone uses Proportional, Integral, Derivative (PID) logic for staging. PID staging will consider three things when deciding to activate a water heater: how far the water temperature is from the target temperature, how long the temperature has been there, and how quickly the temperature is changing. PID logic improves efficiency and averts temperature drops in your domestic hot water.
Product Includes
Specifications
KW 399
General Information
Type
Tankless Water Heater
Product Line
Keystone
Medium
Medium
Medium refers to the substance that carries heat through the heating system. Systems are either designed to use either Hot Water or Steam as a medium, and components are usually specific to one or the other.
Hot Water
Fuel Type
Fuel Type
To create heat, some form of fuel is required. Fuel Type specifies what the product uses as an input to create heat.
Natural Gas
Combustion Type
Combustion Type
Condensing appliances use leftover thermal energy from combustion gases to heat water in a secondary heat exchanger, resulting in higher efficiency and lower exhaust temperature.
Condensing
Vent Type
Vent Type
Products that use combustion (burning) of fuel to create heat also create potentially dangerous gasses that need to be exhausted (AKA "Vented"). Depending on the product, venting can be done via a chimney, through a side wall, or use a second vent to provide fresh air to the appliance.
Direct Vent
Modulating/Staging
Modulating/Staging
Stages are unique speeds or levels that equipment can operate at. More stages allow for better fine-tuned control of output, which improves comfort and efficiency. Modulating equipment can operate across a range of levels, giving the highest level of fine-tuned control. Learn More
Modulating
Storage Type
Tankless
Mount Type
Floor
Installation Location
Indoor
Gas Conversion Kit
Included
Performance
Maximum Input Capacity
Maximum Input Capacity
The Maximum Input Capacity describes how quickly the appliance will use fuel when delivering it's maximum capacity. The units may change depending on the fuel being used.
399000 BTU
Minimum Input Capacity
80000 BTU
Flow Rate at 70F Temperature Rise
Flow Rate at 70F Temperature Rise
Flow rate measures how much hot water your heater can deliver. Click Learn More to determine the appropriate temperature rise to use based on your location. Learn More
11 GPM
Efficiency Type
Thermal
Thermal Efficiency
96.3 %
Maximum Flow Rate
50 GPM
Electrical Data
Voltage
120 Volts
Phase
1
Frequency
60 Hz
Dimensions
Primary Vent Pipe Diameter
4 Inches
Gas Connection Size
3/4 Inch
Cold Water Inlet
2 Inches
Hot Water Outlet
2 Inches
Product Height
38 Inches
Product Width
24 1/2 Inches
Product Depth
31 Inches
Product Weight
346 Pounds
Certifications
ASME Certified
Yes
AHRI Certified
Yes
ISO Certified
Yes
AHRI Reference Number
1852163
Warranty Information
Parts Warranty
Parts Warranty
A warranty is a safeguard from defects in manufacturing and can vary in length and terms. Some manufacturers require registration for extended warranty benefits, be sure to check out features and the warranty document. To see the manufacturer's warranty statement, click on the Manuals tab. Learn More
1 Year
Heat Exchanger Warranty
5 Years
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Triangle Tube Keystone - 399,000 BTU - Tankless Water Heater - NG - 11 GPM - 96.3% Thermal Efficiency
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