Rinnai Hot Water Fault or Error Code 51

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Rinnai Continuous Flow Hot Water Heater Fault or Error Code 51 Troubleshooting Guide

Is a Rinnai fault code 51 flashing on your tankless hot water system’s display monitor?

rinnai hot water system

What does a error code 51 signify?

A Rinnai error code 51 signals that there is an issue with the systems inlet water temperature sensor, this code will require a qualified technician to rectify the problem. You can attempt to remove the Rinnai fault code yourself by turning the hot tap off and on and by also pressing the on/off button on your monitor.

The code 51 will be removed if it was simply a trip of the system, but if the code remains then an investigation of the hot water unit will be required.

Who can repair a Rinnai fault code 51?

For an expert repair to rectify the Rinnai fault code 51 call the hot water experts from Jim’s Plumbing.

Our fully qualified plumbers are highly trained in all aspects of Rinnai hot water heaters and understand all Rinnai fault codes, including error code 51.

When you call to book a local plumber from Jim’s please state that a fault code 51 is displayed on your Rinnai hot water heater monitor.

This will allow for a prompt repair with your attending plumber not needing to leave site to source any parts as we will initially know what the exact problem is and how to resolve.

Jim’s Plumbing cover all metropolitan areas of Adelaide, Melbourne, Perth, Brisbane, Sydney and Canberra and we have a plumber available near you 24/7 – including all weekends and public holidays.

We guarantee a same day gas fitting or plumbing service and can even have a plumber knocking on your door within an hour* of your call in an emergency.

What is required to rectify a Rinnai error code 51?

To clear the Rinnai code 51 on your tankless hot water heater your attending plumber from Jim’s will fist check the sensor wiring harness for any loose or damaged connections from the sensor leading back to the PC board.

If no damaged connections are present the next step is to remove the inlet water temperature sensor and check for any scale build up.  Any substance found here will be effectively removed.

If the fault code 51 is still showing your Jim’s plumber will check the resistance readings of your hot water unit and if all correct and no other issues are located then the inlet water temperature sensor itself is faulty and will be required to be replaced.

Preventative maintenance on your Rinnai hot water heater

You can greatly reduce the risk of fault codes appearing, or any other issues, on your Rinnai hot water heater by organising a periodic service for the appliance.

Hot water heaters should be serviced according to each individual manufacturer’s recommendations – usually once every two years, and this will keep your appliance running at optimum efficiency.

Ask your attending Jim’s Plumber for the full benefits of preventative maintenance techniques on your Rinnai hot water heater.

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