Why is HVAC Preventative Maintenance Important?

Save money for the important thingsWhole-home heating and cooling systems are expensive, there’s no other way to put it. Replacing a whole-home comfort system, especially with a quality system that will last 10+ years, can cost thousands of dollars. Money like that, to use a popular saying, “doesn’t grow on trees.” An unexpected failure in either your heating or cooling system will dip into your emergency fund, and make you allocate that money from something you really want to spend your money on, also known as in our business as a “luxury” item (think a trip, new car, boat, bike, etc.). Here at HVAC Parts Shop we don’t want you to have to go through this, so that’s why we stress to our customers preventative maintenance. Simple, preventative maintenance can help lengthen the life of your air conditioner and furnace, and put off those costs, allowing you to spend your money on what you really want.

First and foremost, changing the filters for the system is a priority.  If a filter is clogged up, the air is unable to get through. If the air can’t get through the filter, components of the system begin to overheat. When they overheat, that’s when the system can start to shut down, or even break down, leading to costly repairs or a full out necessary replacement. Preventative maintenance, like regular filter changes, can lengthen the life of the unit and help it run more efficiently, saving you money in both the long and short term. Depending on the size of your filter, the time between replacements can vary.

Generally, we suggest a one-inch filter gets replaced every month, and some of the thicker ones can last up to three-four months. However, regular checks are recommended to make sure it is not too clogged up and the unit is still running efficiently. Click here to view our selection of filters if yours needs to be replaced.Run Capacitor

Another important item to change on a regular basis is your capacitor. The capacitor regulates the electrical current running through the equipment. We recommend replacing them every 4-5 years. After a few years a capacitor can get weaker. This can cause all sorts of problems for your equipment. A weak capacitor puts unnecessary stress on the motor and compressor. This stress can cause them to overheat, or not start at all. A weak capacitor can even cause the motor and compressor’s life to be shortened. Replacing them every few years is a relatively cheap and easy fix for do-it-yourselfers. When you switch out your capacitor, it is important to discharge yourself and the capacitor before removing it. This will make it safe to touch, and can prevent an unpleasant jolt of electricity.

Contactors are important to change every 4-5 years as well. Contactors are connected to all of the main electrical. They are connected to the compressor, fan motor, thermostat, and capacitor. When the thermostat calls for cooling, the contactor closes the circuits. These closed electrical circuits let the electricity flow through the contacts and power the unit. As a contactor gets older and dirt gets into the contacts, it becomes more difficult for the circuits to close. If they can’t close properly, the contactor tries to push electrical current harder, and that causes extra stress on the electrical contacts. With extra stress on the contacts, the electrical equipment is stressed too. In order to prevent the unnecessary stress on the air conditioner, it is recommended to replace the contactor every 4-5 years.

These simple tips are the type of preventative maintenance that will help keep your home comfort system running efficiently. Replacing these parts consistently will help lengthen the life of your system. Replacing these parts will help keep the costs to a minimum, and can let you focus on the important things in life. If you need any of these parts, or other technical support, feel free to check out our website at We’ll be happy to help you

Different Types of Capacitors for your HVAC System

The main function of a capacitor in an HVAC system is to provide the additional torque needed to get a unit running and the electricity needed to keep it running. There are different types of capacitors and you will find different types in different HVAC systems. As in the video, let’s begin by explaining start capacitors:

Start Capacitor
Start capacitors can be seen in outdoor units such as air conditioners and heat pumps, and are in addition to a dual run capacitor, which we will cover later. Generally only high-end factory models come with a start capacitor, but start capacitors or super boost capacitors can be installed in older or smaller units in order to increase torque and quicken start up.

The purpose of a start capacitor is to get the compressor up and running as fast as possible. As the compressor begins running, the potential relay will disconnect the capacitor from the electrical circuit. The two parts go hand-in-hand and it is a good idea to purchase them together.

A super boost capacitor is another type of start capacitor that has a potential relay built into it. This capacitor is very easy to install. It has two interchangeable wires – one that connects to the common terminal and one that connects to the HERM terminal. It can easily be stacked next to the run capacitor in your unit. If you have any additional questions about installation, please feel free to contact us. We are here to help.

We can also help identify the size and ratings of your capacitor so that you can replace it correctly. It is common for the label to become rusty and hard to read. As long as you know your unit’s model and serial numbers we can find the right capacitor.

Dual Run Capacitor
Dual run capacitors are also found on outdoor AC units and heat pumps and come in a variety of shapes and sizes. They are able to support two motors – the compressor motor and the fan motor. The dual run capacitor runs continuously while your unit is running. It has three terminals: HERM connects to the compressor, fan connects to the fan motor and common connects to the contactor. It is imperative to connect each wire to the appropriate terminal.

Again, it is important to read your data sticker in order to purchase the correct size of capacitor. The data that you should be looking for are the microfarads and the VAC, or voltage amp current. The capacitor in the video shows a capacitor with 45 + 10 microfarads. This means that 45 microfarads will go to the compressor and 10 microfarads will go to the fan motor. The new capacitor that you purchase must have the same amount of microfarads. VAC, however, is slightly different. If you are replacing a 370 VAC, you may replace it with a 440 VAC, but you cannot replace a 440 VAC with a 370 VAC.

Single Run Capacitor
Single run capacitors are generally used in furnaces. They have two terminals, HERM and common. The two wires that come from the furnace’s blower motor can connect to either terminal.

Over time, single run capacitors can get weak and you will begin having problems keeping your furnace running. If your fan motor is making a humming sound, this is a sign that you need a new capacitor. Note, it is dangerous to use your hand to give your blower motor a push. Please refrain from doing so.

Two additional safety tips for replacing your capacitor are:

  1. Make sure the power to the unit is off, both at the unit and at the circuit breaker.
  2. Deactivate the electrical charge, by using an insulated screwdriver and touching each terminal. It is also a good idea to wear insulated gloves.

Thank you for watching (and reading) our video. Until next time, stay warm!


Does Your Furnace Need a New Capacitor?


Capacitors are a key component to your furnace’s overall performance and just like most parts, will eventually wear out. Here are some indications of a weak or faulty capacitor:

1. Noisy! – If your furnace’s motor is running a lot louder than normal this is a sign that you might need a new capacitor. Also, a worn-out capacitor will make a clicking sound as the furnace starts up.

2. Burning Odor – An old or malfunctioning capacitor will cause the motor to overheat and may even cause the wires to melt, hence the burning odor.

3. Will Not Start – A furnace with a bad capacitor will not start, but before that happens you may notice that it won’t run at full power or will run sporadically. This is a good indication that the capacitor needs to be replaced.

4. Visual Signs – A faulty capacitor can become swollen with bulging ends. In some cases a capacitor may even swell so much that the ends blow open and begin leaking oil.

5. Rising Gas/Electric Bills – A weak capacitor causes the motor to run less efficiently and your bills to go up.


What Is A Capacitor?

capacitorA capacitor is used in most HVAC systems, including furnaces. It has two main functions – it provides the additional torque needed for starting a unit and gives the unit the electricity needed to keep it running. They are on continuous duty while the motor is running.

Capacitors provide a steady supply of electricity to the fan motors and help the blowers move hot air through your system. In other words a capacitor is similar to a battery, storing electricity and stabilizing currents.

Without a capacitor your furnace’s motor will not start and the unit will not run. In fact, if the motor in your furnace won’t start, the capacitor is likely the problem.

Capacitors are categorized by microfarads and voltage. Microfarads are what measure the capacitors ability to store an electrical charge. A capacitor will range from 1.5 to 100 microfarads and will be classified at either 370 VAC or 440 VAC.