Rinnai Tankless Water Heater Troubleshooting

Smart water heaters like the tankless series from Rinnai are dominating households these past years. However, just like any device or equipment that are technologically advanced, they, too encounter problems. Fortunately, these water heaters have error codes which alert the homeowner if something is off with their systems and these codes have several meanings to make troubleshooting easier.

Here are some of the problems Rinnai tankless water heater owners can encounter and tips on troubleshooting these problems:

Note: One of the complaints of users of tankless water heaters is that hot water does not flow instantly. However, this is really not a problem at all since these water heaters are designed this way.

1. Water Coming From The Heater Is Way Too Hot.

If the temperature is set just enough and the water is still too hot, there are several reasons for this. One can be sedimentation build-up which can happen with years of use. The solution here is flushing or descaling to get rid of the sediments. For reduced water flow that results to water too hot, it might be that water is being blocked as it flows. Check the pipe and the passageways of water. Another reason is a broken temperature sensor. Fix this by correctly positioning the sensor or if this does not fix the problem, replace sensor. Another culprit is a loose connection or rusted burner.

2. No Hot Water Is Flowing.

Step 1: Check the electrical power supply if it is plugged. Also, see to it that the gas and water supply systems are functioning. If yes, the shut valves coming from the main water supply are off.

Step 2: If it is not yet giving off hot water, heck the burner and the flame rod.

Step 3: Go to the control panel and check if there is an error code flashing. Locate the reset button and press it. This can solve the problem.

3. There Flame Rod Does Not Ignite And The Burner Is Out.

Step 1: Check if there electrical power is supplied to the Rinnai water heater. Next, check the gas and water supply.

Step 2: For the gas line, ensure that the gas type and pressure are accurate and the gas line has the correct size. Next, bleed the air from the gas line. Rinnai tankless water heaters use either propane or natural gas.

Step 3: Afterwards, locate the flame rod and the wiring harness. Check for loose wirings and damage on these parts.

Step 4: Check for condensation.

Step 5: Check for issues on the gas valve as well as the vent system.

4. Code Error 3 Is Flashing Which Can Mean There Was a Power Interruption During Operation Or a Burned Fuse.

Step 1: Turn off all the hot water.

Step 2: Flip the circuit breaker connected to the heater and replace the fuse.

Step 3: Locate the temperature controller and push the on and off button. Repeat it two times. For power outages in the area, repeat the steps a number of times.

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