Top 5 Rational Error Codes and What They Mean to You

General Parts Group Service Technician learning and working on Rational Error Codes

By Pat Finley – Master Certified Lead Technician

General Parts Group is proud to have been a service partner to Rational from the mid-’90s. Since this time the popularity of Rational combi-ovens has grown, and as Rational has grown its market, so have we, with all major General Parts locations now being Rational certified authorized service agents (ASA).

Being a Rational Certified partner means we can support Rational equipment both during the warranty period and after. Rational sets standards specifically designed to maximize the ROI of the unit which means that our technicians undergo rigorous in-person training and have quick access to mandatory replacement parts, all of which have the added benefit of reducing downtime.

In the event that your combi-oven needs attention, it can actually let you know!  Your unit will more than likely display an error code, knowing what the error code means will help you decide whether it can be resolved ‘in-kitchen’ or whether to call your service agent.

The manual for your model has a list of all the error codes, but just in case that is not too handy, here are the top five codes General Parts helps to resolve for its customers:

Error 10: SC pump without function

This occurs when the unit is trying to flush or empty the boiler. You should be able to see or hear water in the drain. If you do, you may have a scaled-up level probe, and the unit may think it’s full of water when it is actually empty. If no water is coming out of the drainpipe, you may have a bad motor or another issue that needs attention from a technician.

Error 12: CDS without signal

The CDS is a counter that determines how much water is being used. It is a crucial component in determining the amount of water in the boiler. This is used to calculate certain parts of cleaning, as well as if your boiler needs to be descaled. If you get an Error 12, verify that your water supply line is connected and “water shut-off” is on. If these are good, you may need a service technician to dig deeper into the issue.

Error 25: Clean jet water circulation faulty

This can occur during cleaning. During the “clean cycle”, there are multiple components working together. If any one of them doesn’t do its duty, you can get a service 25 error. If you put your unit into a “clean cycle” and you do not see any or little water sprayed from the top into the blower motor, it will generate this error. In this event, check to ensure your water supply is turned on. If your water supply is OK call your ASA to resolve the issue.

Error 40: Care Pump not functioning

Care Control is a process of cleaning or descaling the boiler. The Care tabs are put into the care drawer. Water is then sprayed onto them, breaking them down into a solution,  then pumped into the boiler/steam generator. To ensure proper operation, only use approved Care tabs from Rational. In the event of a service 40, call your local trained service provider.

Error “RESET” gas (rES)

This indicates an issue with the gas system, if applicable. The unit did not sense flame and is therefore locked out. You can verify that the gas supply is turned on to the unit and the gas hose is properly seated into the quick connect. If both of those are correct, seek service from your local, factory-trained ASA.

If you have a different error code,  you can download the appropriate manual here;

If you have more questions about the care and maintenance of your Rational oven, then reach out to us  at (888) 498-1238 or online here