A forced air oven or hot air oven is simply an oven with a fan. Most domestic and laboratory ovens these days have a fan to help distribute the heat evenly around the oven.
Without a fan you will often get cold or hot spots, meaning uneven heating, drying or testing.
How a Forced Air Oven Works?
In A Forced Air Oven the fan circulates the air throughout the ovens compartment. This forced circulation of the hot air means an even temperature throughout the interior of the oven ensuring good test results where ever the sample is placed in the oven. This is done by blowing hot air past the sample meaning there isn't any cool spots in the corners or around the product as it heats up.
Fresh air in drawn in from the rear or bottom of the oven and is blown into the compartment past the heating elements and onto the sample or product being tested.
Often there is a port on the top of the oven this can be left open if there is going to be a lot of moisture in the product, this will help speed up the drying process.
In a non forced air oven the temperature can vary a few degrees Celsius in a good quality forced air oven this will be under 0.5 degrees Celsius.
When ever temperature is critical to your process or its part of a quality check you should have your oven calibrated at regular intervals. We have found ovens in the past with errors of more than 15 degrees Celsius. For non critical work a single position calibration would be sufficient, however we would recommend a survey of 5 positions at the top middle and bottom of the oven.
If you have any questions please do not hesitate to contact us.AML sell a range of Laboratory Ovens and Furnaces and also provide a full calibration and repair service.