BUNN Coffee Brewer Message Heating Time Too Long: Service Required
Heating Time Too Long means the tank did not heat in the allowed time. The manual says service is required. Switch the brewer off and call a technician.
High: the tank cannot be heated, so the brewer cannot make drinks.
- Code
- Heating Time Too Long
- Maker
- BUNN
- Equipment
- Coffee brewers
- Applies to
- New Infusion Series (ITB, ITCB, ITCB HV, ICB SH/DV/Twin) display message
What does BUNN Heating Time Too Long mean?
After the brewer is switched on, the control gives the tank a set time to reach the ready temperature. If the tank has not got there when that time runs out, the control displays Heating Time Too Long and stops trying. This is a stronger message than Temperature Too Low, which is the normal wait. The programming manual's Troubleshooting page lists two causes: a tank heater failure and a control board or thermistor failure. Its action is a single line, service required. The heater may not be warming the water at all, or the thermistor may be reading incorrectly so that the control thinks the water is not heating. A brewer that is run on after this message may give weak coffee or none, and it should not be left running unattended with a possible heater problem. Writing down how long the brewer had been on, and whether the water at the tap of the tank felt warm at all, helps a technician decide whether to bring a heater or a board.
Affected models and control systems
BUNN Infusion Series bean-to-cup brewers: ITB, ITCB and HV models, and the ICB and Twin. Other BUNN brewer lines use a different message list.
Code numbers and their meaning can change between control generations. We match the full model and control before acting on a code.
What you may notice
- Heating Time Too Long on the display
- Brewer will not start a drink
- Water in the tank cold or only warm
Possible causes
Listed in BUNN's documentation
- Tank heater failure
- Control board/thermistor failure
Other likely causes — what usually sits behind Heating Time Too Long on this control. A technician confirms which one it is before any part is replaced.
- Scale on the heating element that insulates it
- Heater relay on the board not closing
- Thermistor lead loose at the board
Safe checks before calling for service
- Switch the brewer off at its switch.
- Check that the brewer is plugged in and the breaker is on.
- Do not keep restarting the brewer repeatedly.
- Call for service and note how long the brewer heated before the message.
How a technician diagnoses Heating Time Too Long
- Read the message and confirm the supply voltage.
- Check heater continuity and the heater relay output.
- Measure the thermistor resistance and compare it with its chart.
- Check the control board output to the heater.
- Replace the heater, thermistor or board as needed.
- The heater and relay carry line voltage and high current.
- The tank holds hot water and pressure.
- Telling a failed heater from a failed thermistor takes measurements.
How Heating Time Too Long differs from similar codes
Heating Time Too Long is the failure message. Temperature Too Low is the normal warm-up wait.
Technical reference
- Maker documentation
- BUNN owner support
- Edition
- 41581.0003 D 3/20; troubleshooting page stamped 41581.3 120210
- Models / control
- New Infusion Series (ITB, ITCB, ITCB HV, ICB SH/DV/Twin) display message
- Section
- Troubleshooting (cont.), p.32
- Checked
- October 2026
We use the maker's document to read the code and do not reproduce it. Always confirm the complete model and control before applying these steps.
Related BUNN coffee brewer error codes
Is this the same as Temperature Too Low?
No. This means the allowed heating time ran out.
Can I try again?
Once, after switching off. If it repeats, service is required.
Is the heater always bad?
No. The manual also lists the control board and the thermistor, and a technician measures each before replacing anything. A thermistor that reads wrong can make a working heater look dead.
Need help with BUNN Heating Time Too Long?
A technician confirms the cause on site and gives you the price in writing before any work starts.