Rinnai Hot Water Fault or Error Code LC, 00 or LC0 – LC9

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Rinnai Continuous Flow Hot Water Heater Fault or Error Code LC, 00 or LC0 – LC9 Troubleshooting Guide

Troubleshooting your Rinnai continuous flow hot water heater has now become even easier with the use of their self-diagnostic fault code display.

rinnai hot water system

If your Rinnai tankless hot water heater has a water temperature controller installed an error code will flash on the display monitor should a fault occur within your hot water unit.

One of the Rinnai error codes that may display on the monitor is fault code LC – this can also show up as error code 00 or LC0-LC9.

What do the Rinnai hot water error codes LC, 00 or LC0-LC9 indicate?

If a fault code LC, 00 or LC0-LC9 is flashing on your Rinnai hot water heater systems digital monitor this signifies a scale build-up in the heat exchanger.

The heat exchanger is what heats the water in the unit prior to it reaching your hot water tap, and is one of the hardest working parts within the hot water system.

The LC, 00 or LC0-LC9 Rinnai fault codes are the only codes that will allow your continuous flow hot water heater to continue operating. You will notice that the display monitor will flash between the fault code and the temperature setting while the controller continues to beep.

You can attempt to clear a Rinnai LC, 00 or LC0-LC9 code yourself by turning your hot water tap on and off and also turning the power of the temperature controller off and then on again. This may clear the code, but if it remains or clears only to return again then a service call will be required to resolve the scale build-up issue in the heat exchanger.

Troubleshooting procedures for Rinnai fault codes LC, 00 or LC0-LC9

If any of the error codes LC, 00 or LC0-LC9 codes are showing the heat exchanger will be required to be flushed to prevent any damage. This is a job for a fully qualified professional.

Call the Rinnai hot water heater experts from Jim’s Plumbing any time of the day or night for a prompt and reliable repair to rectify the LC, 00 or LC0-LC9 fault code. We have a plumber available 24 hours a day, 7 days a week, including all public holidays situated near you – if you reside in any metropolitan suburb of Adelaide, Perth, Melbourne, Sydney, Brisbane or Canberra.

When you call Jim’s Plumbing you are guaranteed a same day service with normal rates offered until 7.30pm on weekdays. Should you require an emergency plumbing or gas repair then expect to see one of our mobile plumbing vans pulling into your driveway within an hour* of your call.

Usually these Rinnai error codes LC, 00 or LC0-LC9 occur most commonly in tankless hot water heaters using hard water. Hard water must be treated to prevent scale build-up or damage within the heat exchanger.

If your hot water heater does lock out in the event of an LC, 00 or LC0-LC9 fault code occurring you can operate the system temporarily, while you wait for the heat exchanger to be flushed, by pushing the on/off button on the controller 5 times. This will allow for the unit to operate for a further 70 hours.  It is recommended to have the scale build-up cleared as soon as possible as you don’t want to risk further damage to the unit, resulting in extra costs. When you call in a local plumber from Jim’s we will never leave you waiting for long.

Phone us anytime, 24/7, on 1300 133 509 or book your plumber through our online booking form for a prompt, reliable, affordable and professional service with customer satisfaction guaranteed.

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