Data released from the U.S. Department of Energy shows that almost 75% of American homes have an AC system installed. These systems consume around 6% of the energy produced in our nation and we spend approximately $26 Billion running them per year. Keeping our indoor temperatures at a comfortable level is important when we need to relax in or even work from our homes. But, despite our obvious need and uptake of these systems, it’s surprising that many people don’t know how they work. In this article, we will answer six common questions about HVAC systems.

1.  What HVAC Size Unit Do I Need?

This is not an easy question to answer because everyone has different circumstances and there are a number of key factors to consider, including the type of home, the size, the number of floors, insulation levels, home orientation, the number of windows, and many more. These factors are all considered in a complex load calculation that a heating and cooling specialist will use to work out the system size that you need. The system must be matched carefully, if it’s too large it can increase humidity and if it’s too small it will run constantly and drive up your energy bills. Mismatched equipment can lead to short-cycling problems, which can damage your heating and cooling system leading to an expensive repair bill. Contact your local HVAC specialist and ask about a load calculation and energy audit, when you’re planning for a new system installation.

2.  How Often Should I Replace the Air Filters?

As a rule of thumb, heating and cooling experts recommend that you should change the air filters every month on the same day, if possible. But, there are times when you may need to consider more frequent air filter changes. They are an increased level of dust, you own pets, there are higher contaminants levels nearby, and more. A clean air filter can prevent many other problems in your home and it will save you money in the long-term. Buy your air filters in bulk to save money and to make sure you always have spares available when you need them. If you can’t remember the last air filter change, change it now and schedule your future changes from this point. If you check the air filter and it’s dirty, it’s time to change it for a fresh one.

3.  Do I Need to Cover Outdoor Units in the Fall and Winter?

It may seem like a good idea to cover the outdoor units throughout the fall and winter months to prevent an accumulation of dirt, grime, and other debris. But, the cover can trap moisture inside that can lead to corrosion problems, and operating with a cover on can cause damage. The best approach is to fit a cover in the earlier part of the fall when dead leaves and other debris can enter the units. During late fall and winter, leave the cover off because the units are designed to withstand the harsh outdoor conditions. Before the warmer weather arrives, clean the outdoor units and schedule some essential maintenance.

4.  Should I Replace My Indoor and Outdoor Units at the Same Time?

In almost every scenario, this is the best option for a number of important reasons. First, most AC systems and external heat pumps are manufactured to match a corresponding indoor unit. If mismatched equipment is used, it may work, but it will not have the same performance or energy efficiency as matched units. The second reason is that if you purchased your existing indoor and outdoor units at the same time, they are probably reaching the end of their useful lifespan anyway. Switching one only may increase the frequency of repairs, the performance may suffer and the energy efficiency will be lowered. Finally, when you get both units at the same time, you will have a warranty that covers your entire system. This means that you won’t need to pay the full cost of any repairs during the length of your warranty period.

5.  Why Do My AC Units Freeze?

When many people see ice on the surface of the AC units, they may believe that the system is working correctly. This is a common misconception and the exact opposite is true. The air conditioning does not cool the home, it removes heat from the home and this makes it cooler. This may seem like a trivial distinction, but it’s an important concept to understand and there should be no freezing or ice on the surface of your equipment. The most common cause of freezing is a lack of refrigerant that lowers the pressure and efficiency of the entire system. It’s important to contact a local HVAC specialist to recharge the system with refrigerant. Mixing the wrong refrigerant types or recharging the system incorrectly can cause damage and a drop in performance. Another potential cause is a lack of airflow caused by dirty evaporator coils that need to be cleaned. Finally, if your blower motor is failing, it will lower the airflow which will cause freezing. If you notice freezing, get your local heating and cooling specialist to take a look.

6.  How Often Should I Schedule Essential Maintenance?

The heating and cooling units need essential maintenance to ensure that they are working as intended by the manufacturer. Most HVAC experts agree that an annual inspection for both systems is the best approach. This should take place prior to the start of each heating and cooling season when the systems are not essential. As an example: the AC system should be inspected and serviced a month or two before the start of summer when it’s needed. During a maintenance visit, the HVAC technician will test the system, inspect the components, lubricate moving parts, clean dirty areas, carry out repairs and offer valuable advice.

Hopefully, we’ve managed to answer some of the more common HVAC questions to your satisfaction. But, if you have any further problems and you need to schedule some essential maintenance, contact your local HVAC specialist today.