Takagi Water Heater Dip Switch Settings: A Complete Guide

Most of my previous articles related to Takagi tankless water heaters were created for both beginners and experts. But this time I’ve come up with a different article especially written for the experts. It’s about the Takagi water heater dip switch settings (Tankless).

For gas type selection the Number. 1 and 2 DIP switches are mainly used. When it’s propane gas, turn on switch 1 and turn off dip switch 2; for natural gas, turn off switch 1 and turn on dip switch 2. Again for default fan fan motor speed keep the 3, 4, and 5 switches to the OFF position.

Here I mentioned just 2 settings but there are 5 more important DIP switch settings. In this article, I’ll discuss them all. So, continue reading.

Takagi Water Heater Dip Switch Settings

DIP switch settings aren’t just a single setting. The settings can be different in terms of different purposes and functions. Also, correct DIP switch settings are crucial for the heater to work well.

In this article, I’ll be covering DIP switch settings for gas type selection, fan motor speed, altitude settings, vent length, temperature control, exhaust temperature, and freeze protection. Aside from that, you’ll learn about troubleshooting the error code that occurs due to incorrect DIP switch settings. So, read on.

Dip Switch Settings for Gas Type Selection (Position 1 and 2)

The first two DIP switch positions (1 and 2) are dedicated to selecting the type of gas used by the Takagi water heater. There are 2 options, Propane and Natural Gas. 

1. For propane gas type: Keep the number 1 switch ON and the number 2 dip switch is OFF.
2. For natural gas type: Ensure the number 1 switch is OFF and the number 2 dip switch is ON.

NB: This is the most common DIP switch setting for gas type selection. Models like 240 (T-H3J), 340 (T-H3S), and 540 (T-H3) use the same settings. Still, I would recommend you check your user manual and confirm it. 

01. Dip Switch Settings Fan Motor Speed Control

Positions 3, 4, and 5 of the DIP switch are used to control how fast the fan motor works. Here the specific functions are denoted as FM+, FM-, and Input-. 

Usually, the fan motor speed is increased automatically. However, the default DIP switch configuration for the fan motor is labeled 3, 4, and 5 switches are set to the OFF position. 

NB: The given setting is for the 240 (T-H3J) and 340 (T-H3S) models. When it’s the 540 (T-H3) model, the Dip Switch positions are 2,3, and 4

Advanced Tip: You can also manually change the Dip switch position to change the fan speed manually. You can change it between a range from -7% to 26% (Depending on the models) by changing the Dip switch positions. You can check the HIGH ALTITUDE SETTINGS in your Takagi manual for detailed information.

02. DIP Switch Settings for High-Altitude Installations

A very important thing you should know is the proper DIP switch settings for High-Altitude installations. The setting is different for different models of Takagi water heaters. Below I’ll mention the settings for a few common Takagi tankless water heaters.

i) 240HX3/340HX3 Models

DIP switches are also used for high-altitude installations. Below, I’m providing the DIP switch settings for high-altitude installations on the 240HX3/340HX3 models.

• Default (0 to 2,000 ft): In this setting, DIP Switch No. 3 is OFF, DIP Switch No. 4 is OFF, and DIP Switch No. 5 is OFF.
• 2,001 to 3,000 ft: For altitudes between 2,001 to 3,000 ft, DIP Switch No. 3 remains OFF, DIP Switch No. 4 is turned ON, and DIP Switch No. 5 is kept OFF.
• 3,001 to 5,000 ft: At altitudes ranging from 3,001 to 5,000 ft, DIP Switch No. 3 is OFF, DIP Switch No. 4 is OFF, and DIP Switch No. 5 is turned ON.
• 5,001 to 7,500 ft: In this setting for altitudes between 5,001 to 7,500 ft, DIP Switch No. 3 is OFF, DIP Switch No. 4 is turned ON, and DIP Switch No. 5 is also turned ON.
• 7,501 to 10,100 ft: For the highest altitude range of 7,501 to 10,100 ft, DIP Switch No. 3 is turned ON, DIP Switch No. 4 is turned ON, and DIP Switch No. 5 is turned ON.

ii) For 540HX3 models

Now I’ll mention the lower bank of DIP switches setting is given for the 540HX3 models.

• Default (0 to 2,000 ft): For this setting, DIP Switch No. 2 is turned OFF, DIP Switch No. 3 is also OFF, and DIP Switch No. 4 is OFF.
• 2,001 to 3,000 ft: For altitudes ranging from 2,001 to 3,000 ft, DIP Switch No. 2 remains OFF, DIP Switch No. 3 is turned ON, and DIP Switch No. 4 stays OFF.
• 3,001 to 5,000 ft: At altitudes between 3,001 to 5,000 ft, DIP Switch No. 2 is OFF, DIP Switch No. 3 is OFF, and DIP Switch No. 4 is turned ON.
• 5,001 to 7,500 ft: In this altitude ranging from 5,001 to 7,500 ft, DIP Switch No. 2 is OFF, DIP Switch No. 3 is turned ON, and DIP Switch No. 4 is also turned ON.
• 7,501 to 10,100 ft: For the highest altitude range of 7,501 to 10,100 ft, DIP Switch No. 2 is turned ON, DIP Switch No. 3 is turned ON, and DIP Switch No. 4 is turned ON.

NB: The given 2 configurations are for the indoor models. For outdoor models the setting is different. So, check the manual for the confirmation. 

03. DIP Switch Settings for Vent Length

In this segment, I’ll discuss an important part – DIP switch settings for vent length. To make the ventilation system work properly it’s necessary. However, there are different settings for different vent types. Let’s get them below. 

i) Dip Switch Setting for Two-pipe, direct-vent installation

When it’s a two-pipe direct vent let’s check out the DIP switch setting. 

For 3″ Venting

• Default (5 to 20 ft): For the vent length ranging between 5-20 ft, set switch 3 to ON and Switch 4 to OFF. This configuration is the default for vent lengths ranging from 5 to 20 feet.
• 21 to 40 ft: For vent lengths between 21 to 40 ft, the settings are to set switch 3 to OFF and Switch 4 to OFF.
• 41 to 70 ft: For vent lengths from 41 to 70 ft, keep switch 3 to ON, and switch 4 to ON.

For 4″ Venting

• Default (5 to 50 ft): The default setting for vent lengths of 5 to 50 ft is switch 3 to ON and switch 4 to OFF.
• 51 to 100 ft: For vent lengths between 51 to 100 ft, set both Switch 3 and Switch 4 to OFF.

ii) Dip Switch Setting for Single Pipe with Room-Air Intake Installation

Now for single vent pipe installations check out the based on the vent diameter and length:

For 3″ Venting

• Default (5 to 45 ft): In the default setting for vent lengths between 5 to 45 feet, set switch 3 to ON and switch 4 to OFF.
• 46 to 70 ft: For vent lengths between 46 to 70 ft, configure switch 3 to OFF and switch 4 to OFF.

For 4″ Venting

• Default (5 to 50 ft): The default setting for vent lengths of 5 to 50 ft set switch 3 to ON and Switch 4 to OFF.
• 51 to 100 ft: For vent lengths spanning from 51 to 100 ft, keep both the switches 3 and 4 to OFF.

04. DIP Switch Setting for Changing Temperature

Using the remote control you can easily change the temperature. But there is another way to adjust it by using the DIP switches. You can even adjust it to various temperatures compared to remote control.

While working with different Takagi models, I found the DIP switch settings different for different models of Takagi water heaters. I’ll show you the settings for some common models. Let’s start with the 910/910 ASME models. 

i) For 910/910 ASME

If you’re a user of this model you can adjust the temperature to 8 different levels. Let’s see how to do it.

• 100 °F (38 °C): To set the temperature at 100 °F, activate the No. 1 DIP switch while ensuring that both the No. 2 and No. 3 switches are in the off position.
• 115 °F (46 °C): For setting the temperature to 115 °F, keep both the No. 1 and No. 3 DIP switches in the off position and No. 2 in the ON position.
• 120 °F (50 °C): For a temperature of 120 °F, ensure that all No. 1, No. 2, and No. 3 DIP switches are in the off position.
• 135 °F (57 °C): To set the temperature at 135 °F, turn off both the No. 1 and No. 2 DIP switches and turn on the No. 3 switch.
• 145 °F (63 °C): For a higher temperature of 145 °F, keep both the No. 1 and No. 2 DIP switches turned on, and the No. 3 switch turned off.
• 155 °F (68 °C): To set a temperature of 155 °F, activate both the No. 1 and No. 3 DIP switches and keep the No. 2 switch in the off position.
• 165 °F (74 °C): For setting the temperature to 165 °F keep both the No. 2 and No. 3 DIP switches on, and turn off the ‘No. 1’ switch.
• 185 °F (85 °C): For the highest temperature setting of 185 °F, ensure that all ‘No. 1’, ‘No. 2’, and ‘No. 3’ DIP switches are turned on.

ii) For 240HX3/340HX3/310CX3 and 140 Indoor/Outdoor Model

Unlike the 910/910 ASME, the mentioned model comes with lower temperature settings. Let’s check them below. 

• To set the temperature to 120 °F (50 °C), keep the No. 9 in the OFF position.
• For keeping the temperature to 140 °F (60 °C), turn the No. 9 in the ON position.

iii) For 540HX3/510CX3 and 540P Indoor/540P Outdoor Mode

Now, here are the DIP switch settings for another 4 common Takagi models

• ‘No. 5’ in the OFF position sets the temperature to 120 °F (50 °C).
• ‘No. 5’ in the ON position sets the temperature to 140 °F (60 °C).

05. Dip Switch Setting for Exhaust Temperature Control

The final DIP switch position, 10, is used for activation and deactivation of exhaust temperature control. Here the default setting is the Number 10 switch is OFF. However, you can also enable it by turning the Number 10 switch ON, and then the exhaust temperature control will be active. [For the 240 (T-H3J) and 340 (T-H3S) models]

Again, for the 540 (T-H3) model, the same function works with the Number 6 switch. 

Warning: Do not change this DIP switch unless the technical service department guides you. Only turn on this DIP switch when connecting your unit to a CAT III/IV metal vent with a maximum temperature rating of 480°F. Switching on this DIP switch turns off the exhaust temperature control. Ignoring this warning can be dangerous. It can cause personal harm, carbon monoxide exposure, or even fatal consequences.

06. Dip Switch Setting for the Freeze Protection Firing System

When you’re a user of the 540 (T-H3) model there is a bonus setting for you. Using the number 8 DIP switch you can enable or disable the freeze protection firing system. By default, it remains disabled. You can enable the number 8 DIP switch to enable it.

07. Troubleshooting Guide for Incorrect Dip Switch Settings in Heating Systems

The error code 031 indicates that there is a problem with the dip switch setting. If the dip switch settings are wrong, the heating system might not work well and cause different problems. Understanding these codes is the first thing to do in figuring out and fixing the problem. Let’s see how to troubleshoot the error code.

i) Power Off

The first thing to do when fixing the wrong dip switch settings is to turn off the power to the heating system. This ensures safety and is important for preventing any further complications during the troubleshooting process.

ii) Accessing Dip Switches

Remove the front cover of the heating system to locate the dip switches on the center of the computer board. These switches are typically found on the left and right banks.

iii) Check Dip Switch Settings

Now check the dip switch settings on both the left and right banks. Double check the gas-type dip switch, as they are the very reason for this error.

iv) Default Settings

Usually, the dip switches are set to their regular positions, unless you need a special setup. Make sure to follow the default positions in the system manual when adjusting the switches.

v) Easy-Link Systems

For Easy-Link systems: The main heater needs to have switch number 10 turned on on the right side. The other heaters (the ones that follow) should have switch number 10 turned off on the right side. Connect the communication wires to the plugs on the following heaters.

FAQs:

Final Verdict

I think you’re now clear about all the Takagi tankless water heater DIP switch settings. In the beginning, I’ve already mentioned this is not any simple task and a newbie user shouldn’t try it. Any wrong step can cause harm to both the user and the heater. However, if you are confident that you can do it then must take note of the default setting before trying one. If there is any mistake get the switches back to the default setting.

That’s all for today. Now before I leave I would like to suggest another article on the Takagi water heater not igniting.