There are many factors that affect the overall health and efficiency of the HVAC system in your Sacramento, California home. However, static pressure easily ranks among the most important. This is the measurement of resistance to airflow within your heating and cooling system’s ducting. When static pressure is at the perfect level, you’ll enjoy lower home energy bills and increased home comfort. Your HVAC equipment will also last longer and have fewer problems. Following is everything you need to know about static pressure, including how it’s measured, what happens when it’s off-balance, and how to avoid common issues in this area.
Understanding Static Pressure
When you turn your water hose on and let the water flow out naturally, you’ll likely get a gentle yet continuous stream. However, as soon as you block the hose opening with your finger or thumb, both the rate of the water’s flow and its force will invariably increase. This is how increases in static pressure impact the flow of air in your HVAC system. However, rather than placing your thumb over any of your HVAC system’s openings to adjust its static pressure, you might decrease the size of air return ducts or extend them. In many instances, significant changes in static pressure are not the result of conscious actions on the part of homeowners or their HVAC technicians.
Damaged ducts, blocked ducts, and many other factors can impact static pressure too. These are changes that happen behind the scenes where they can’t be easily spotted. When they do occur and when they cause significant changes in static pressure, many noticeable symptoms will present. Home energy bills might suddenly skyrocket even though building residents haven’t changed their schedules or behaviors. The living environment might develop hot and cold spots. Frequent repair issues may occur. Worse still, heating and cooling systems might utterly fail long before reaching the end of their expected lifespans.
There’s an Ideal Level for Static Pressure
Both too much and too little static pressure can cause problems. When this measurement is off, HVAC systems can become incredibly noisy. They’ll lose efficiency, and they won’t last as long. Many HVAC contractors agree that 0.5 inches of static pressure is ideal. At this level, HVAC systems aren’t subjected to accelerated wear, and noise levels remain moderate when heating or cooling systems are on. Maintaining static pressure at 0.5 inches is also beneficial for HVAC ductwork. HVAC air ducts are less likely to develop pressure-related leaks or other forms of damage at this level.
What Happens When Static Pressure Becomes Too High or Too Low?
Static pressure in your home’s HVAC system may be too high if your heater or air conditioner is constantly overheating or showing other signs of being overworked. Excess static pressure forces heating and cooling equipment to work harder in order to compensate for limited airflow. When static pressure is too low, it usually means that there’s continuous air loss within the system. Even when your air conditioner or heater is constantly running, indoor temperatures will remain virtually unchanged. In some cases, this means that the vast majority of conditioned air is being deposited behind the drywall where it will have virtually no impact on the temperature or feel of the living environment at all.
Factors That Cause Static Pressure Issues
Problems with static pressure often have to do with improper equipment sizing. If you have a heater or air conditioner that’s too large or too small for your home, you aren’t going to get the ideal amount of airflow and the measurement for static pressure will always be off. Both excess and insufficient static pressure increase overall system wear, force HVAC equipment to work harder than it normally would, and lead to shorter lifespans.
Sometimes ducting isn’t sufficient. Your ducts may not be long enough to support proper airflow. This is a common issue in older homes that aren’t built to accommodate modern HVAC systems. As HVAC technologies advance and equipment designs change, existing ductwork must often be modified to reflect these changes. In instances where HVAC air ducts are old and leaky, HVAC systems will have continuous problems maintaining the ideal static pressure until they’re repaired or replaced.
There are also instances in which problems with insufficient or excess static pressure are the direct result of poor HVAC air filter maintenance. Air cannot flow freely when air filters are excessively dirty or clogged. There’s even the possibility of having the wrong filter type. If the filter you’ve installed isn’t rated for or compatible with your system, static filter issues can arise.
How Problems With Low and High Static Pressure Are Corrected
The first step in correcting static pressure issues is identifying their source. Excessively high or excessively low static pressure is a symptom of a larger problem. Sometimes homeowners are able to identify the source of airflow problems on their own by looking for blockages and air duct leaks. Retracing your steps to determine whether you’ve forgotten to change out your air filter or whether you’ve purchased the wrong filter type could point you to your answer.
When improperly sized HVAC equipment is the culprit, replacing it with a correctly sized unit is the only sensible choice. Furnaces or air conditioners that are too large will short-cycle throughout their lifespans. If they’re too small, they’ll be forced to run all of the time. The only way to reliably avoid HVAC sizing issues is by always having furnace and air conditioner selection handled by the HVAC company that’s been hired for installation.
How to Avoid Static Pressure Issues in Your HVAC System
One easy way to avoid issues with excessively low or high static pressure is by diligently maintaining your HVAC equipment. Filter changes should be performed according to the manufacturer’s recommended schedule. For most models, this is once every one to three months. However, certain factors may make it necessary for you to change your system’s air filter more often. This may be the case if you:
- Have indoor pets
- Live near a freeway or a busy street
- Haven’t landscaped your yard
- Live near an active construction site
You can also check HVAC air vents or grilles for accumulations of dust, dirt, lint, or other debris on a regular basis. If you’re seeing lots of build-up in these areas, it means that your air filter is probably clogged and that your air ducts are dirty too. HVAC air ducts should be inspected and cleaned on a regular basis as well. Based upon the needs and location of your home, HVAC air ducts should receive professional inspections and cleaning approximately once every two to four years. This will give your provider the opportunity to catch and fix problems with leaky, bent, or otherwise damaged ducts early on.
Given that imbalances in static pressure shorten the lifespan of HVAC equipment, these are issues that are best resolved right away. Fortunately, static pressure measurements are always taken during comprehensive HVAC maintenance service. Scheduling annual air conditioner and heating system maintenance will ensure that static pressure changes don’t leave you without a functional heater or air conditioner.
At Gallagher's Plumbing, Heating and Air Conditioning, we offer reliable, affordable HVAC maintenance services to residents of Sacramento, California and the surrounding areas. Homeowners can also turn to us for water heater installation, water purification services, air duct cleaning, and indoor air quality services. If your HVAC system isn’t performing like it should, give us a call today.