Did you listen to the marketing cry and decide to “Install a Rheem”? It’s always a solid choice to keep that hot water coming on “Steady, hot and strong” – but what happens when yours goes wrong and you’re left with freezing cold water after a long, muggy day? Well, don’t fret, because like any sophisticated appliance, they aren’t infallible. But what do you do when your Rheem is no longer going steady, hot and strong? Answer: Do some Rheem hot water system troubleshooting!

1. Do you see an error code?

Particularly if you have a continuous flow Rheem, it’s time to familiarise yourself with the various helpful error codes that your system flashes up when something’s gone wrong. Look up the Rheem code, and follow the recommended actions. Some common fault codes for Rheem continuous flow systems are below.

  • 11 Ignition failure at start up
  • 12 Flame failure during operation
  • 16 Outlet water temp too high
  • 31 Inlet thermistor open circuit
  • 33 Outlet thermistor open circuit
  • 90 Decrease in fan motor ventilation

2. Do you have a heat pump?

Are you benefitting from the superior energy efficiency and smaller carbon footprint of a Rheem heat pump? You’ll also helpfully see fault codes indicated through the flashing lights on the controller, and they will vary depending on the model – for instance, the codes for the 310L model are different from the 325L model because of the specific operational issues they face.

3. Do some general troubleshooting

Have you explored the Rheem-supplied general troubleshooting guide for all the most typical issues with Rheem hot water systems? It explores the wide range of problems across the full Rheem HWS range, rather than specific issues related to a particular model or type. Don’t have enough hot water, the temperature is wrong, you’ve got a hot water leak, you hear a noise? It’s definitely worth a look.

4. Could it be the pilot light?

With a little bit of luck, if your Rheem gas-powered hot water heater is not working, it might just be the pilot light that’s gone out for whatever reason. Rheem has created a video guide to relighting a piolet light for your convenience.

5. Do you have a water leak?

How much do you know about the function of your system’s temperature relief and expansion control valves? If your system has them, they’ll allow a little bit of water to escape during the heating cycle – because water expands as it gets hotter. Test to see if it’s more than a bucket-full of water over 24 hours, because if it’s less than that, stop worrying.

6. Is your temperature up-and-down?

Temperature fluctuation is a common issue with Rheem systems, so check if your heater is being affected by any water flow restrictors or water-saving low-flow taps. If you don’t know what to do about them, call your friendly plumber. And if the problem is simply that the water is not quite hot enough, or a little bit too hot, you’ll need a hot water plumber to do any modifications or to check the tempering valve.

7. Check your warranty information

If you’re having clear and obvious major problems with your Rheem, let’s troubleshoot your Rheem hot water system by seeing if it’s still under warranty. Get your model number, jot down your specific system’s serial number, and give Rheem a call on 1300 556 036 to verify your warranty status.


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8. Have you kept up with maintenance?

There are few things Rheem expects you to get done either by a plumber or all by yourself. These involve:

  • Checking and exercising the relief valve
  • Inspecting the condition of the anode rod
  • Keeping the area around your system clear of debris & obstructions
  • Occasionally draining water (a flush) to get rid of sediment.

Rapid Service Plumbing: Your friend for hot water health

Your Rheem may be reliable, but it’s still a very complex bit of technology. Hopefully, our exclusive Rheem hot water systems troubleshooting guide has resolved your issue, but if not or you’re sure something more serious is going wrong, give the friendly team at Rapid Service Plumbing a call. We’re available 24/7 in emergencies, we always offer no-obligation quotes and upfront pricing, and we’ll also guarantee the quality of our workmanship – forever! Our plumbers serve the greater Sydney regions including Canterbury-Bankstown, City of Sydney, Eastern Suburbs, Hills District, Inner West, Sutherland Shire, North Shore, and Northern Beaches. Not only that, our Melburnian neighbours can now experience high-quality plumbing services as we have expanded to Melbourne! Rapid Service Plumbing is only ever a single call away for advice and a rapid response, so don’t hesitate to get in touch.