Rinnai Hot Water Fault or Error Code 73

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Rinnai Continuous Flow Hot Water Heater Fault or Error Code 73 Troubleshooting Guide

The Rinnai tankless hot water heaters come equipped with a handy self-diagnostic tool should any faults arise with the system.

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These error codes allow yourself, or your service technician, to quickly and easily see what the issue may be that is causing your hot water heater to fail and in turn provide a prompt resolve.

The Rinnai hot water fault code will flash on your systems digital monitor, or status monitor if you have a hot water temperature controller installed. One of the codes you may come across is the fault code number 73.

What is a Rinnai fault code 73?

The Rinnai error code 73 signifies that there is a fault in relation to the burner thermocouple of the hot water unit.

The burner thermocouple is like a sensor that sends a signal to the gas valve to allow the gas valve to let gas through to the burner.

If the burner thermocouple begins to fail the wrong signals will be sent to the gas valve resulting in the burner not lighting, meaning no hot water for you.

Rinnai error code 73 repair

When it comes to rectifying a Rinnai error code 73 on your continuous flow hot water heater you will require the services of a fully qualified technician.

For a prompt and reliable repair in relation to the burner thermocouple fault call the Rinnai hot water experts from Jim’s Plumbing.

We have a team of highly experienced and fully qualified hot water plumbers available covering all metropolitan areas of Adelaide, Melbourne, Perth, Sydney, Brisbane and Canberra 24/7.

If you find yourself with no hot water and a Rinnai fault code 73 flashing on your hot water system monitor we guarantee a same day service.

We can also have a plumber to your location within the hour* in a gas or plumbing emergency.

When it comes to troubleshooting the Rinnai fault code 73 your attending plumber from Jim’s will inspect the wiring harness of your continuous flow hot water heater to ensure there are no loose or damaged connections from the burner thermocouple back to the PC board.

They will ensure all dip settings are set correctly and check that the manifold gas pressures are set as per manufacturer’s instructions.

In most instances the burner thermocouple will need to be replaced if it has become faulty.

If the thermocouple is replaced and the Rinnai error code 73 remains then the PC board will be required to be replaced also.

Although a service call is required to rectify a Rinnai error code 73 you can attempt to remove the code yourself by turning your hot water tap off and then on and by pushing the on/off button on the systems monitor off and then on.

If the fault code was just a trip of the system it should now be removed.

If the fault code 73 remains, or shows up again shortly after, then call the experts from Jim’s Plumbing for a fast, reliable and affordable repair first time, every time!

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