The Takagi Company recommends that consumers have a professional service person troubleshoot and repair internal problems with its water heater. Users are advised to check the service and installation manual first, to see if the problem is external in nature. External problems can often be resolved by the user.
Some of the external problems that cause a Takagi water heater to malfunction include improper venting, gas line issues and water temperature fluctuations. Using the wrong type of ventilation equipment can cause hazardous gas leaks to occur. This problem often arises due to the choice of a standard B-vent instead of approved stainless steel, ABS or schedule 40 PVC vent pipes, which are compatible with the unit.
There is a tendency to hook the Takagi water heater up to an existing gas line, which is too small to allow gas to flow to the unit properly. It is important to read the installation manual for information about safe gas line connections. Consumers are also advised to select the heater that is designed for either natural gas or liquid propane gas. Improper gas line hookup can also cause fluctuating water temperatures. If the gas line is not the issue, users should check to see that the temperature gauge is set at 122 degrees Fahrenheit, which is the default setting.