Grindmaster Grind’n Brew GNB Coffee Brewers
Current line. 4 model numbers in this series.
Model numbers in this series
Find yours on the data plate. Letters after the base number usually mark the voltage, finish or door and do not change the repair.
- GNB-10H
- GNB-11H
- GNB-20H
- GNB-21H
Repairs this series usually needs
- Er1 water fill error
- Er2 and Er3 thermistor errors
- Er4 heater error
- Brew basket removed while the light is flashing
- Grind not dispensing from the auger or hopper
The Grind’n Brew GNB brewers grind fresh coffee, then brew it, in one machine. The data plate shows GNB-10H, GNB-11H, GNB-20H or GNB-21H. A microprocessor handles brew volume and tracks the grinder and the heater.
When something fails, it shows Er1 through Er4. Er1 is a fill problem and the brewer will still grind but not brew. Er2 and Er3 are thermistor errors, and Er4 means the heater did not warm the water.
Because it has a grinder and a hot water system in one cabinet, we check both: the hopper and auger for the grind, and the tank, thermistor and heater for the brew. Older units get an honest assessment of repair cost. Tell us the code on the display when you call, and we will say whether an owner step could clear it first.
About this series
- Brewer with a built-in grinder and auger-fed coffee hoppers
- Programmable brew volume
- Models GNB-10H, GNB-11H, GNB-20H and GNB-21H
- Error codes Er1 to Er4
Other Grindmaster coffee brewers series
Will the GNB still grind if it shows Er1?
Yes. Er1 is a water fill error. Fill and heating shut off and brewing is disabled, but grinding is still allowed. Check the water supply, then call us if it returns.
How do I clear a GNB error?
Hold the UP key for 5 seconds, or cycle power, as the owner's manual lists. If the error returns, the cause is still present and we should test it.
Do you repair older GNB brewers?
Yes. We repair older GNB brewers, the price is in writing before work, and we are honest when a repair is not worth it for the age of the brewer.
Book repair for your Grindmaster Grind’n Brew GNB Coffee Brewers
Tell us the maker, the model number from the data plate and what the unit is doing. We confirm a three-hour arrival window and give you a written price before any work starts.