Takagi T-KJr2-IN-NG Tankless Water Heater Reviews

On Takagi’s line-up of water heater, Takagi T-KJr2-IN-NG is one of the two smallest units. The closest resemblance to this one is the Takagi T-KJr2-IN-LP which requires a constant flow of liquid propane, instead of natural gas, to work. Given its features and specifications, we think it’s safe to say that it’s a mid-range offering from the company. With maximum flow rate of 6.6 gallons per minute, you can never go with more than two showers.

Still, on the positive note, this heater is efficient enough to qualify for an approval from Energy Star. In case you wonder, the thermal efficiency published by Takagi regarding this model is 81% – 83%. That’s even higher than AO Smith mid-range water heaters. We’re going to discuss Takagi T-KJr2-IN-NG in more details from here on.

Takagi T-KJr2-IN-NG Tankless Water Heater Features :

Takagi T-KJr2-IN-NG Tankless Water Heater– Qualified by Energy Star
– Having thermal efficiency of 0.81-0.83
– Capable of supplying maximum flow rate of 6.6 GPM
– Having maximum gas input of 140,000 BTU
– Requiring 4-inch category III stainless steel venting
– Dual thermistors for constant temperature controlling
– 10-year warranty for heat exchanger and 5-year warranty for parts


In the water heater industry stateside, the name Takagi isn’t really well known but don’t let that fool you. This company is a giant on its hometown country, Japan, and their products are all rated with outstanding quality. Takagi T-KJr2-IN-NG might not be recommended by too many HVAC experts and contractors alike but its ease of use, build quality and performance are on-par with the industry’s leading products. In case you’re still in doubt, the Energy Star rating on the heater should ease you. Also, its thermal efficiency is rated to be in between 81% – 83%, which is pretty high for a mid-range water heater.

The maximum gas input on Takagi T-KJr2-IN-NG is 140,000 BTU. With that, the heater is capable of providing maximum flow rate of 6.6 GPM with constant output temperature. Strangely, with such specifications, the unit still struggles to supply hot water instantly. You’ll get cold water during the first 3-5 seconds after you open the faucet. After that, hot water flows out constantly. The thermostat it comes with must be hooked up to a 120V AC outlet but good news is that in most cases you can connect the unit with your existing gas and water lines.


Every purchase of Takagi T-KJr2-IN-NG is eligible for 10-year warranty for the heat exchanger and 5-year for parts. However, this is only valid if you entrust the installation to the company’s licensed technician. The problem is since the company is not originated in the U.S., all the personnel they have here aren’t very competent with stuff. Worse, they are totally expensive. The venting option isn’t very flexible as well for the unit will only work if you pair it with 4-inch category III stainless steel venting.


Takagi is probably not a popular brand on HVAC industry in North America but you should know that the company is a leading player in Japan. Their products are on-par with the consumer’s most preferable product and they have great rating as well in terms of efficiency. Overall, we think Takagi T-KJr2-IN-NG is a fantastic water heater, despite its extremely costly installed cost.