Refrigerants

Low superheat normal subcooling is a less frequent AC problem. It happens when some culprit is decreasing superheat, but, very importantly, it doesn’t affect subcooling. Let’s look at what is causing low superheat and normal subcooling issue, and fix it (to avoid compressor flooding). Namely, we can look at culprits that cause low superheat here, … Read more

“Subcooling is normal, but I get high superheat. What is causing this? How can I fix high superheat normal subcooling?” This is quite a common air conditioner issue. Namely, we can find cases of high superheat normal subcooling by: Looking at every culprit that causes high superheat here. Removing the culprits that cause high or … Read more

Low superheat high subcooling is a common issue with AC units. There are 5-6 low superheat causes and 3 high subcooling causes. By comparing these causes, we can see which ones are the reason we have low superheat and high subcooling. Here is a chart of low superheat causes (on the left) and high subcooling … Read more

We use subcooling for a range of AC diagnostics. Both high subcooling and low subcooling will give us a key insight into what might be wrong with our air conditioner. To fully take advantage of our subcooling measurements, we are going to check these two insights: Low Subcooling Causes. As we will see in the … Read more

Low superheat can flood your compressor. That will ruin the compressor, and you will likely have to spend $1000s for a new air conditioner. That’s why it’s very useful to understand what causes low superheat and how to fix it. We are going to cover all 6 low superheat causes, going one-by-one, detailing why low … Read more

High superheat is an AC problem that won’t go away by itself (except due to the #4 cause). We have to fix high superheat. In order to do that, it’s particularly useful to understand what causes high superheat in air conditioners. There are 6 common high superheat culprits that we always check, and we’ll go … Read more

One of our readers asked us if there is a target subcooling chart. Namely, we do have the most extensive target superheat chart here; shouldn’t there be a similar target subcooling chart as well? Well, there is none. That’s because the target subcooling doesn’t significantly depend on the outdoor temperature (like the target superheat). Example: … Read more

When diagnosing air conditioners, you will probably need to consult the target superheat chart. Here we are going to take a structured approach to how to calculate and use target superheat. Namely, we are going to go through these 4 very useful resources for target superheat: Target Superheat Formula. In order to calculate target superheat, … Read more