Resources & FAQs

Frequently Asked Questions

What is an Argon Purge Kit?

A purge kit is designed to inject intern gas such as argon gas into the furnace heating chamber to reduce oxygen content. Since regular box furnaces are not hermetically sealed, small amounts of oxygen content are still in the heating chamber depending on inert gas flow rate. If a customer requires high purity argon atmosphere, the Sentro Tech tube furnace or vacuum and atmosphere controlled furnaces are recommended. A typical Sentro Tech vacuum/atmosphere controlled furnace can reach 50PPM or below oxygen content.

What could an exhaust port be used for? Is it required in conjunction with the purge kit?

An exhaust port is used to exhaust smoke or fumes from the furnace. It can be used by itself without an argon injection port.

What is a forced exhaust port?

A forced exhaust port is a motorized fan to force fumes or off gas from the furnace chamber to stack or vent to outside building. It is much more powerful to exhaust fumes from the furnace by forced exhaust than nature draft exhaust port. Venting amount can also be controlled by a damper in forced exhaust port.

What is a PC Data Logger?

A data logger will record furnace temperature history and stores the data into a computer.

What is the temperature uniformity along the length of the hot zone at 1200° and 1300°C?

Depending on the furnace size, typically box uniformity is about +/-5°C in furnace heating chamber. If better temperature uniformity is required such as +/-2°C, then air circulation fan is needed.

What is an air circulation fan?

Air circulation will circulate hot air inside the heating chamber to achieve excellent temperature uniformity.

How long is the life of MoSi2 heating element? How much do replacement elements cost and is it easy to replace them?

MoSi2 heating elements last very long under normal operation conditions and we have seen some of our customers have not had to change heating elements for years. The cost of heating elements varies with the size, and can range from $150 to $700. It is very easy to replace these elements.

What is overtemp controller and extra thermocouple?

Independent thermocouple and over temperature controller will shut off the power to heating elements when thermocouple reading is high than pre-set high alarm temperature in over temperature controller.

What are UL/CSA certified parts for? Why is this needed?

CSA Certification or CSA US field evaluation requires that all electric parts in furnace controller box are either UL or CSA certified. If this furnace requires CSA or US field certification, then these parts will need to be UL/CSA certified.


Muffle furnaces: A type of box furnace for high temperature applications.

Sintering furnaces: These types of furnaces are used by dental and other laboratories for ceramic sintering. In the sintering process, heat and pressure are used to transform ceramic material.

Brazing furnaces: This is a high temperature furnace that works well in any application requiring brazing.

Desktop furnaces: This type of furnace, also called a bench top furnace, takes up very little space in your laboratory.

Ashing furnaces: This type of furnace burns products in an enclosure until only ash remains. Ashing furnaces also scientifically weigh the product through the entire combustion process. 

Dry ovens: Drying ovens are used in drying, sterilizing, baking, heat treating, annealing, and other applications.

Rotary tube furnaces: Perfect for laboratory use, rotary tube furnaces contain a working tube that permanently rotates to process powder and granular materials.