Air conditioners have two jobs: 1) Decrease temperature, 2) Decrease humidity. We have seen a lot of cases when the AC is cooling but not removing humidity (think 70% humidity levels). We will explain why you see this high humidity in the house with AC running; it’s quite paradoxical, and there is a good reason … Read more
“My AC compressor runs for a few minutes then shuts off? This is not normal. What is causing it? How can I fix it?” Alright, let’s tackle this one. A lot of people ask us why does the AC compressor shut off after 2-3 minutes. We will explain the possible reasons why this keeps happening, … Read more
In HVAC, delta T measurement is used to confirm adequate heat transfer at the indoor evaporator coil. We are going to look in-depth at what is delta T in HVAC, how we measure it, and what low delta T and high delta T mean. Namely, delta T in heating and cooling is the temperature difference … Read more
“Condensation is dripping from the ceiling vent; is this AC vent sweating normal? How to stop condensation on air vents?” This is quite a common AC vent problem. We see water droplets on air vents (usually on the ceiling vents). The ducts are sweating profusely and dripping on our walls, floor, carpets, furniture, and so … Read more
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
Low superheat low subcooling is quite a paradoxical AC problem. How can you have low superheat and low subcooling at the same time? We will explain what causes low superheat low subcooling issue in air conditioners, and how to fix it. Here is what low superheat and low subcooling means: We get low superheat when … Read more
It’s not rare to see high superheat high subcooling problem in AC diagnostics. When both superheat and subcooling are elevated, there are only 2 possible culprits. We will look into these culprits and lay out how to fix high superheat high subcooling AC problem. For this situation, we need to have: Actual measured superheat is … Read more
High superheat low subcooling is the most common combination we find when diagnosing AC units. In order to normalize both high superheat and low subcool, we have to understand why these 2 key parameters are abnormal. Namely, we have written about: High Superheat Causes here. We have high superheat when the actual measured superheat is … Read more