When the humidity is high, you feel hot and sultry even in a cool environment. In such weather, you think that the best place to be is indoors where the climate is controlled. Did you know that the humidity or moisture in the air affects the performance of your HVAC? If not, there is no need to feel ashamed. The aim of this post is to help you understand a bit more about the effects of humidity on HVAC performance.
When the humidity inside the home is too high or too low, attaining the best possible comfort indoors is not easy. The good news is that most modern HVAC systems have an inbuilt dehumidification mechanism that keeps a check on the relative humidity. The relative humidity is the amount of moisture present in the air as compared to how much it can ideally hold at that specific temperature.
Sensible Heating And Cooling vs. Latent Heating And Cooling
There are two ways in which the HVAC systems cool the air –
1.By raising or lowering the actual temperature. This is known as sensible cooling or heating, as the case may be. It is most beneficial in a dry climate when no dehumidification is required.
2.By getting rid of the moisture in the air. This is known as latent cooling or heating. It is most beneficial when the humidity levels are high. However, you may need to adjust the actual temperature to regulate the “feels like” temperature.
How Humidity Affects HVAC Performance
Your central air conditioner removes not only heat but also moisture from the air inside the home. It works longer and harder when the humidity is high to maintain a comfortable temperature. If, however, the cooling capacity of the unit is not good, it will never cope well in excessive humidity. Similarly, it will be ineffective if it is a system of the wrong size or an old unit.
An important fact is that an oversized AC will not necessarily give the cooling that you desired. Not only that, but it will also increase your electricity bill and also add to the wear and tear of the machinery. An HVAC system can provide adequate humidity control only when it is properly sized for your home and that too by a professional.
Some signs of high humidity inside the house are –
1.Sultry and sweaty feeling even when inside the house,
2.A musty odor bordering on unpleasant in your home.
3.Fogging up of windows.
HVAC Humidity Control
We have spoken that the HVAC unit controls humidity. It’s time to learn how it does so.
The work of a compressor is to cool the air. As the air inside the home reaches the desired temperature, the compressor shuts down. During this time, the evaporator coil is still cold. It starts warming slowly on the shutting off of the compressor. As it warms, moisture or small water droplets form on the coil due to condensation. Now the main question is, what happens to this moisture or condensation? Let’s study the answer in two possible scenarios.
1.When The Weather Is Humid – In a humid climate, the fan should stop along with the compressor. This gives a chance for the condensation to drip down into the collector pan and drain away from the drain line. If the fan does not stop but instead keeps on running, it causes the moisture or condensate to re-evaporate and enters back into the house with the airflow. Essentially speaking, the humidity keeps circulating with no change.
2.When The Weather Is Dry – In dry weather, it is best to allow the fan to run a while longer even after the compressor has stopped. This helps to get rid of any water that may be sticking to the evaporator coil or just sitting and collecting in the pan. The evaporation of this moisture also cools the air. In this way, you not only save energy but also add to the comfort of your home.
Humidity And Heating Systems
Cold air is generally dry and does not hold moisture as well as the warm air. That is the reason why in cold winter months, your nasal passage dries out, skin becomes dry, sinuses become aggravated, and so on. Your heating system works long to provide warmth, but the house is still cold. The reason is that the humidity has fallen below the recommended level of 40% to 50%. In such a situation, you need to bring humidity within the recommended levels so that your abode can become warm and cozy and provide you respite from the chilling cold.
Humidification In Winters For Better HVAC Performance
In winters, HVAC humidity control means increasing the level of moisture in the air. This is possible only through humidification. You can install a humidifier on your HVAC system. The humidifier will add back moisture to the air prior to letting it flow through your entire home. When the air becomes moist, it will warm your house faster and give you relief from symptoms that arise due to air dryness.
Dehumidification In Summers For Better HVAC Performance
Moisture adds warmth to the air; therefore, in summers, you want to get rid of it so that the air becomes cool. The only way to achieve this is through dehumidification. Thankfully, setting your AC on the appropriate temperature will automatically do the job. However, if you set the temperature really low, the dehumidification operation gets compromised. Your choice is to correct the temperature setting or to install a dehumidifier in your home.
Final Thoughts On HVAC Humidity Control
Depending on the weather, the need for moisture in the air varies. In summers, you want to be free of the clammy feeling, and so dehumidification is needed. As against this, the air is so dry in winters that you want to add back humidity. Your HVAC can perform the desired function adequately for optimum comfort provided that your unit is not very old and properly sized. Sometimes adding a humidifier or dehumidifier will go a long way in making your home even more soothing and welcoming. In all this, take guidance from an AC service professional for the best results.