What is the performance of argon filling in insulation glass unit?

Argon filling is a common technique used in insulated glass units (IGUs) to improve their thermal performance. Argon is an inert gas that has a higher thermal resistance than air, the most commonly used gas in IGUs.

The thermal performance of an IGU can be quantified by its U-value, which measures the amount of heat that is transferred through the unit. The lower the U-value, the better the insulating performance of the IGU. The U-value of an IGU can be improved by filling the space between the two panes of glass with argon instead of air.

The filling of argon gas to an IGU can reduce the U-value by up to 16%, which can translate into significant energy savings in a building. For example, if an IGU with an air gap has a U-value of 1.2 W/m2K, filling the gap with argon can reduce the U-value to 1.0 W/m2K.

It is important to note that while argon filling can improve the thermal performance of an IGU, it is not the only factor that affects its overall energy efficiency. Other factors such as the type and thickness of the glass used, the size of the air gap, and the quality of the seal around the unit can also impact its performance.

The points to be considered about argon filling in insulated glass door for fridge/cooler/freezer

First of all is the question of whether or not an initial argon filling rate averaging above 90 percent or higher is achieved. 

Often, manufacturers cannot even achieve the initial fill rate of 90 percent. Many manufacturers are still using rudimentary argon metering equipment and have no way to check units after they’re filled to make sure the proper fill rate is achieved. The technology to fill IG units accurately and test the units after filling is available. Just not every manufacturer is investing in it.

Then comes the uncertainty of whether or not the IG units will be able to retain the argon when the IG units are exposed to the cycling of low temperature to high temperature while being tested with simulated weather conditions, which include s high-humidity and UV-light exposure.

The quality and performance of the spacer and sealants employed can be critical to argon gas retention.

The next comes the anti-fog requirements. Small imperfections may not always prove fatal fogging inside glass cavity, because we are putting desiccant into spacer bar of the IG unit. As moisture vapor finds its way into the unit, the 3A grade desiccant is there to absorb the moisture and trap them inside the molecular sieve.