Takagi T-K4-IN-LP Review

In general, the most prominent benefit of all tankless water heaters is that they keep low-energy usage since hot water is only produced when you need it. Nonetheless, each product offers different specifications concerning capacity, gas inputs, energy efficiency, design, and more.

The Takagi T-K4-IN-LP is an indoor tankless water heater powered by propane gas. It brings 4 temperature presets including 140F, 131F, 122F, and 113F. The main advantages of the appliance are listed below.

Main Benefits

1. Flow Rate

Image of Takagi T-K4-IN-LP.Since the T-K4-IN-LP is designed for mid-sized homes, its maximum flow rate of 8 GPM (gallons per minute) should be enough to provide hot water for almost all residential applications. With such feature, this tankless water heater remains ENERGY STAR qualified. The energy factor is 0.82, which is considered high for gas water heater. It means there will be less energy wasted or less gas used for the appliance to provide hot water.

2. Safety Features

There are some useful safety features included such as freeze protection system and exhaust safety control. Besides making sure that the appliance works under safe circumstances, some controls allow it to work to its full potential. It also features AFR (Air-Fuel Ratio) sensor and overheat fuse cutoff.

3. Compact Design

The overall dimension measures at 20.3-inch H x 13.8-inch W x 8.5-inch D; it weighs only 38 lbs. Direct-vent conversion is available for indoor installation. T-K4-IN-LP can be installed either in horizontal or vertical orientation. The indoor type also includes power cord and remote control.

4. Warranty

Ensuring its quality, Takagi offers useful warranties including 5 years for parts, 12 years for heat exchanger, and 1 year for labor. Those warranties only apply for residential installation. The appliance should be installed by licensed personnel for the warranties to be valid.

Consumer Reviews

Based on consumer reviews, the Takagi’s water heater is generally not disappointing. It brings plenty of features and has good specifications, but it also comes with some disadvantages as well.


According to a consumer, the T-K4-IN is generally easy to install and it does what it promises to do. Another buyer also suggests that the tankless water heater can reduce gas usage up to 40%. Good warranties are provided by the manufacturer, so the appliance can be very efficient in the long run.


The biggest disadvantage is that you need to pay around $300 for installation parts. Nonetheless, assuming that T-K4-IN-LP reduces propane consumption up to 40%, the cost can still be considered inexpensive. A consumer also claimed that his/her tankless water heater broke down (internal leak issue) after 5 years. Now that Takagi offers 5 years warranty on parts, it should not be an issue anymore.

Where to Buy

The Takagi T-K4-IN-LP is available in many online stores. Its original list price in Amazon was $1,468.00, but it is now available for only $780.99 (click here to check the price). This means you can save more than $687 or 47%. You should also know that this item is available with Free Shipping and One-Day Shipping options from Amazon.