Even the best heating and cooling system can waste energy. For example, clogged filters, dirty thermostats, sooty flues, leaky ductwork, and unlubricated fan motors can collectively reduce heating and cooling efficiency by up to 25 percent.
A heating and cooling specialist should check your air conditioner at least twice a year. While some HVAC maintenance tasks are simple, others require a trained pro.
Here’s what you need to know about HVAC maintenance, whether you plan to handle it yourself or hire a professional technician.
Routine HVAC Maintenance
A heat pump only needs a yearly service call by an HVAC technician. The technician will:
- Check the belts, and replace them if needed.
- Check and replace the filters.
- Oil any moving parts.
- Inspect the wiring.
A gas-fired, forced-air heating system has simple requirements, too. You need to change the furnace filter every month or two during heating season, and oil the circulating fan once a year.
Call in a pro every other year to check the:
- Heat exchanger
- Adjust the burner
An oil-fired boiler requires annual maintenance by an HVAC pro to:
- Clean the flue
- Change the fuel filter
- Clean and adjust the fuel jets
Air conditioning units are a little less maintenance intensive. At the beginning and end of each cooling season, you should:
- Clean or replace the air filters
- Vacuum out the unit
- Lubricate the motor
- Have the refrigerant pressure checked, if the unit isn’t cooling properly
For the best results, arrange for service calls before the start of heating or cooling season. You’ll get better attention and have more flexibility when scheduling the appointment.
What to Look for When Hiring a HVAC Company
When you’re hiring a professional, look for HVAC companies that design, install and service the type of system you have. Full-service companies also tend to be up to date on the latest advancements in the field.
Besides checking for liability insurance and workers’ compensation policies, also ask for recommendations. In addition, check with neighbors, friends and family who have used the company over several years.
Ask these questions:
- How well did the system run under the company’s care?
- Did the technicians leave the working area clean?
- How quickly did the contractor respond to emergencies?
- Were the service people punctual when you called with a problem?
A quality provider will have an emergency number that’s staffed 24 hours a day, seven days a week, and enough technicians to respond when the weather is awful and calls pile up.
Buying a New HVAC System
Heating and cooling equipment should last at least 15 to 20 years. If your system is older than this, you might want to have its condition assessed.
Replacing HVAC equipment is a major expense, but modern systems operate much more efficiently than the older units they replace.
Most HVAC contractors specialize in designing and installing the systems of a few manufacturers, so no one shop is going to carry every major brand.
But before you worry about the equipment, you need to find contractors in your area that are knowledgeable and service-oriented.
First, ask neighbors, friends and family what companies they hired to replace a furnace or air-conditioning system. Then, if they were happy with the installation, ask their contractor to talk to you about heating or cooling your house.
You should meet with at least two contractors, and hire someone who installs products from at least two manufacturers.
Don’t forget to consider your service company, if you have one. And remember: while its technicians do have a good understanding of the conditions in your home, you’re under no obligation to hire the same firm for the new system,
When picking a contractor, remember that sizing an HVAC unit by matching it to the home and existing ducting requires skill and experience. A poor design typically results in a system that doesn’t deliver a consistent temperature from room to room. It also costs more to operate.
But it can be even more serious than that. In very tight houses served by ductwork, poor design can lead to backdrafting, a dangerous situation where flue gases are sucked back into the house.
Most HVAC shops are small, so the owner should be involved with the system design and either participate actively in the installation or inspect it when it’s done. You don’t want your system designed by a salesman with no field experience.
Any contractor you’re considering also should offer these products and services:
This process estimates the BTU capacity needed to heat or cool your home. The calculation should include:
- The amount and type of insulation in the walls, attic and floors.
- The type, number, and location of windows and doors.
This data is combined with your regional climatic conditions to determine the size unit you need. Software has made these calculations relatively easy. HVAC technicians who don’t perform them often specify oversize equipment to be safe. That’s dollars out of your pocket now and each time you get an utility bill.
When sizing an HVAC unit, a good contractor will advise you of energy upgrades, such as adding another layer of insulation to the attic. These may allow you to buy a smaller HVAC unit. Although it may not be cost effective to buy the most energy efficient unit on the market, there are minimums you should shoot for. Here’s what a contractor should offer:
- An AC unit (if below five tons) with a 14 SEER or higher.
- A high-efficiency, natural gas heater with an AFUE of around 90 percent.
- A fuel-oil burner with an AFUE of around 85 percent.
- A heat pump with an 14 SEER and 8.2 HSPF.
Use a programmable or setback thermostat (around $40), which contains a timer, to regulate all HVAC systems.
A quality HVAC contractor will show you payback calculations for the various units he offers. These calculations should give you estimates of seasonal operating costs.
Variables the contractor will use in his calculations should include:
- Your regional heating or cooling load.
- The heating or cooling capacity of the units you are considering.
- The cost of various types of energy to allow you to compare the costs of electric, gas, and oil.
Once you receive itemized estimates, compare the costs, and do some research on equipment. Start by visiting the U.S. Department of Energy and Consumer Reports websites, or contact your utility company for comparative lists.
Look at operating efficiency and costs as well as consumer-rated reliability. Then compare your knowledge of the contractors involved and make your decision.
Hot & Cold Tech Speak
Confused by HVAC lingo? Believe it or not, it’s meant to make understanding and buying the equipment easier! These terms allow you to compare apples to apples among units in the same fuel category.
Here are some common terms that you should know:
Seasonal Energy Efficiency Ratio
The Seasonal Energy Efficiency Ratio rates how many British thermal units an air conditioning unit will remove for each watt of electricity consumed.
The higher the SEER, the less you spend on operating costs. Federal law mandates a minimum SEER of 13 for all new air conditioning units.
An air conditioning ton equals 12,000 BTUs per hour. So, a three-ton air conditioner can remove about 36,000 BTUs of heat per hour from your home.
Annual Fuel Utilization Efficiency
The Annual Fuel Utilization Efficiency estimates how much heat a unit delivers for every dollar spent on fuel. The higher the AFUE, the lower your heating bills.
- HVAC System Heating and Cooling Maintenance Tips (video)
- Tips for Maintaining and Buying a Central Air Conditioner (video)
- How to Choose HVAC Air Filters (article)