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Why Is My Refrigerant Sight Glass Cloudy?

You are probably doing weekly maintenance on your equipment, and you notice that the refrigerant sight glass is cloudy. If you are wondering why it is cloudy, we've researched this issue, and here's what we've learned.

Cloudiness on the refrigerant sight glass results from adding incompatible refrigerant that contains harmful additives (lubricants or oils) into the system. Always make sure to check the needs of your system before applying anything.

In this article, we will tackle the reason behind the cloudy look of refrigerant sight glass, what to do about it, and how the sight glass should look. Continue reading to find out the answers to these exciting queries.

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Causes Of Cloudy Refrigerant Sight Glass

Refrigerant is either liquid or gas that can create hot or cold depending on the phase cycle. It is one of the components which can help the equipment operate.

Refrigerant is found most frequently in air conditioners and refrigerators. It works with compressors and evaporators to provide cooler air by absorbing heat from the environment. 

The system consists of a sight glass that detects the presence of liquid refrigerant at the metering device. The sight glass is an excellent tool enabling you to discover any issues with pollution, moisture, and bubbles in the system lines.

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The system's moisture content can be determined using the sight glass with a moisture indicator. It contains a tiny component that changes color in the presence of moisture. However, older sight glasses are not sensitive enough to detect moist conditions. 

You can install the sight glass anywhere along the refrigerant lines and where it can be helpful. Typically, it's installed right after the filter drier in systems with expansion valves. 

A cloudy look could appear on your refrigerant sight glass. When you add refrigerant with incompatible additives into the current fluid in your system, this happens. Don't hesitate to ask experts about what refrigerant is compatible with your system.

What To Do With The Cloudy Refrigerant Sight Glass?

Check the sight glass regularly. Cloudiness is a sign of a refrigerant-level issue. Here is what you can do next:

What To Do With The Cloudy Refrigerant Sight Glass. Why Is My Refrigerant Sight Glass Cloudy

1. Empty the Refrigerant Tank

If skin-eye contact is possible, wear protective gloves and safety goggles. These tools will protect you from any hazardous elements present.

Take the tank and adequately vacuum it to ensure it is completely dry and clean. Pull a deep vacuum below 500 microns to ensure that you remove all the moisture from the system. 

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2. Remove Old Filter Line Dryer

If you have an old dryer attached, you can remove it for the line. On the other hand, if it doesn't have one, you can easily connect a new dryer to the line. 

air conditioner drip valve, filter line drier

Unfasten the Schrader valves on both sides. You can use a thermal protection spray to protect your components and to remove the valves easily. 

Applying it to the valves will come off quickly because it melts its rubber gasket. It is applicable either in removing or attaching the filter dryer.

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3. Attach the New Filter Dryer

Remember to consider the pipe diameter of the fluid line before choosing an appropriate drier for a particular system. The drying capacity is another useful selection factor because there are typically multiple filter sizes specific connection diameters.

Now, determine the location where you want to place your filter dryer. You can easily cut the line for your filter dryer using a pipe cutter. Make sure to measure the length of your filter dryer to have a precise placement.

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After cutting the pipe, clean the opening of the tubes using any cloth. The filter dryer is a single flow. Thus, make sure to attach it according to the flow of the liquid or gas. You can learn the flow direction by the arrow indicated on the device body.

To attach your filter dryer, remove the plastic inserts on both ends and insert the pipe on the opening of your filter dryer. Ensure that they fit with one another. Push it slightly if you feel like it is not yet fully attached.

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Use a torch afterward to join them permanently. Reinstall the Schrader valves.

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4. Add the Appropriate Refrigerant

You must have a reusable dispenser together with your refrigerant refill. Attach the dispenser to your refrigerant refill.

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Afterward, refuel the new refrigerant. Turn on your engine before you apply your refrigerant. Locate the refrigerant fill port, usually found on the left side of the engine bay.

It frequently takes the form of a short metal pipe with two lengths of rubber hose emerging from either end. Carefully avoid coming into contact with any liquid refrigerant gas that is being released under pressure. 

Pull the trigger of your dispenser to release your refrigerant. Keep refrigerant gas away from flames and other hot objects.

What Appearance Should Sight Glass Be?

It must be clear, and you can see the refrigerant come out. Clear glass indicates a good system.

What Are The Indications That Come In Sight Glass?

You can see the refrigerant as it travels down the line using the plain sight window. You can identify system flaws utilizing the information displayed in the sight glass. 

The moisture indicator lets you know if the system is dry or contains moisture. It determines whether the refrigerant moisture content is within a safe range. No further action is required if the moisture content is satisfactory.

The indicator could change color due to moisture in the air if you prematurely open it to the atmosphere.

  • One is yellow, which means wet with moisture. The liquid line at the front end of the expansion valve has too much water vapor.

Too much moisture in the system might cause the oil typically used in modern refrigeration systems to react and produce acids. This is a concern, and you should install new line driers and perform a thorough vacuum.

  • On the other hand, if the indicator is green, there's no water. You are strongly advised not to rely solely on the sight glass for diagnosis. 

Why Is There A Presence Of Bubbles In My Sight Glass?

When bubbles appear in the sight glass, it indicates a refrigerant undercharge, air contamination in the system, or you may have a leak in your system.

Add refrigerant until the bubbles disappear. Don't forget to verify that the drum is in the gas position and activate the drum valve before applying the refrigerant.

If there are only a few bubbles, everything will probably be fine. Bubbles are acceptable if cooling is adequate, the ambient temperature is high, and the system works under a heavy load.  There is a good probability that you will see bubbles in the sight glass if you charge a system properly.

However, it is alarming if you see any bubbles in the sight glass if the system runs at a low load. Thus, always be careful to check every section of your equipment.

It is common for bubbles to appear on the sight glass as the compressor starts up. The bubbles almost completely vanish once the proper pressure is reached, and the color becomes more transparent.

Car condition air ac repair service. Check automotive vehicle conditioning system. Why Is My Refrigerant Sight Glass Cloudy

In Closing

If you disregard safety protocols, you risk death or suffering severe injuries. Thus, you must not forget to wear goggles, a mask, and gloves.

The presence of cloud in your refrigerant sight glass is just due to incompatible refrigerant refill, and you can always vacuum it from the system to remove it. Don't forget to replace your old filter line dryer.

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