Incubator or Oven not heating to setpoint (Omron controller)

If your incubator or oven is reading the correct setpoint, but the temperature feels like ambient temperature, the offset has likely been inadvertently adjusted.

We often receive calls or emails from operators who see that their incubator or oven is set to a particular setpoint, but the inside temperature feels like the ambient temperature. It's nearly always that the operator has accidentally adjusted the offset in the controller instead of the setpoint. This causes an adjustment in the controller that tells it that the ambient temperature is the setpoint, so the controller doesn't call for any heating. 

We'll use 37°C as the desired setpoint in this example. 

  

To set the setpoint

Use the “ <<PF “ button to move the cursor. The digits in SV will flash, indicating that it can be changed. Change the temperature by using the “ UP “ or “ DOWN “ arrows. When the desired temperature is set, leave it for a few seconds, and the digits will stop flashing to the confirm entry. 

The Omron temperature control has a sensor correction parameter that can correct the temperature displayed. This sensor correction parameter is displayed as “ iNS “ (Input Shift). It adds or subtracts a correction value to the displayed temperature to make it read the correct temperature. Press PAGE to display the sensor correction parameter.

If you see the 'iNS' parameter has a number that looks a lot like the setpoint you want, it's likely that someone adjusted this parameter thinking they were entering the setpoint. 

You should change this parameter back to 0.0. 

If this is the problem, the controller will now ask for heating, and you'll see 'OUT1' flashing, indicating the heaters are now heating up. Give the cabinet 5 or 10 minutes, and you should see the temperature on the controller start to increase. 

 

If this doesn't resolve your problem, it could also be:

  • Over temperature thermostat has tripped 
  • Heater has failed

You can contact Thermoline Service for support