Hot air oven works on the principle of dry heat sterilization. In this process, the sample is placed inside the closed container. Then the container begins to heat up. The heat then travels to the sample via conduction. After that, the heat travels towards the core of the sample. Finally, the temperature of the entire sample begins to rise up. When the sample attains a higher temperature, sterilization begins.
The sterilization helps to treat the spores and micro-organisms. So today we will be discussing the operation, applications, handling, maintenance, and the contact details of few suppliers for you to buy the machine in Kathmandu, Nepal.
Hot air oven temperature
The hot air oven temperature is not the same for every kind of machine. The temperature range can slightly differ from one manufacturing company to another. Generally, the temperature of the machine ranges from 50°C to 300°C. Even though the temperature goes up to 300°C, you may not need to set the temperature at its highest value.
Commonly used temperatures for the purpose of dry heat sterilization are as follows.
- 170°C for 30 minutes
- 160°C for 60 minutes
- 150°C for 150 minutes
Design and Working of hot air oven
The design and the operating method of the laboratory hot air oven are similar to that of the incubator. So, you can go through the post of incubator to know about it.
How to use a hot air oven?
(Hot air oven procedure)
- First of all, connect the power cable to the machine.
- Then, turn on the machine. The digital hot air oven will show the display of the present value (PV) and the set value (SV). If needed, you can set the set value (SV).
If the hot air oven is analog, just turn the knob of the thermostat to the required set value.
(Note:- The machine draws a high amount of current at the higher temperature setting. So, due to the flow of high current, the chances of the burn of the heating element (coil) can be high. So, if you want to improve the lifespan of the machine, then I personally suggest you set the temperature at a lower possible value. Similarly, the machine has got three coils on three walls. So, if you have the option in the machine, then I suggest you activate only one or two of the coils. This will make the process of heating the inner chamber slowly. But, this will again prolong the lifespan of the machine. )
- Allow the temperature of the internal chamber to reach the set value.
- Put the sample inside the oven when the temperature reaches the set value.
(Note:- When you put the sample inside the machine depends on the type of sample and task you are performing. Some of the customers use this machine for the purpose of quick drying of the glasswares, metals, etc. In such a case, timing may not be of much concern to the user. So, the sample can be placed inside the chamber, before you turn on the machine.
Others use the machine for the purpose of dry heat sterilization. In such a case, the timing can be of major concern to the user. )
Application of hot air oven
The dry heat sterilization method is useful in those cases, where moist heat sterilization is not possible. But, the samples which undergo chemical changes, melt or catch fire are also not suitable for dry heat sterilization. The laboratory hot air oven for sterilization purposes is recommended for the following objects.
- Glassware such as Petri dishes, flasks, pipettes, and test tubes
- Powders such as starch, culture media, and zinc oxide
- Metal tools such as scalpels, forceps, blades, and scissors
- Materials that contain oils
- Plasticware such as micropipette
I have also seen many customers, use the machine for quick drying of the materials.
- Put the machine on a stable and solid surface.
- Put the hot air oven in an open space. There should be sufficient space for the air to circulate around the machine from all sides. So, it will be better, if the machine is placed at least 2 feet away from the wall and other equipment.
- Do not put the machine near the window. Else the hot air released by the machine can cause the formation of droplets in the windows.
- If you think that the machine is not working properly, then take another mercury thermometer and measure the temperature of the oven. Then compare that value with the preset value of the display. You may also place your hand inside the machine. Then touch the side walls to check if the coils are heating or not.
The maintenance of the hot air oven is the same as that of the normal incubator. So, to know about the maintenance, I suggest you go through the blog of the incubator.
Incubator Vs Oven
There are not many differences between the incubator and the hot air oven. However, a few of the differences between these two are stated below.
|Incubator||Hot Air Oven|
|Low-temperature range (room temperature to 100°C)||High-temperature range (50°C to 300°C)|
|Thin glass wool insulation||High glass wool insulation|
|Low capacity of fuse and switch||High capacity of fuse and switch|
|Low current and power due to thinner heating coil||High current and power due to thicker heating coil|
Supplier of hot air oven in Nepal
There are many suppliers that deliver hot air ovens in Kathmandu, Nepal. Some of them include Menaka Enterprises Pvt. Ltd., Sunrise Surgical House, Eden Technology, etc. Eden Technology is located in Tinkune, Kathmandu. It is an authorized dealer of Osworld products. So, you can contact the supplier to know the price and purchase the machine.