Modern furnaces are more energy efficient and economical than ever. With older systems, the annual fuel utilization efficiency (AFUE) rating could be as low as 56 percent in an older system. Modern high efficiency systems can have an AFUE rating of more than 90 percent. AFUE rating is the percentage of heating fuel converted to heat. A rating of 90 percent means that 90 percent of the fuel converts to heat. Since heating can be as much as one half of the energy usage in a home, efficiency is paramount.
To keep a modern system running at peak efficiency, periodic maintenance should be performed. Over time, dirt and other contaminants can accumulate on parts, electrical components can corrode and thermostats or timers may need fine tuning. Furnace repair should be performed as needed.
Most are aware that furnace filters should be changed on a regular basis, as much as once per month. This is a good idea, since proper filtration controls the air quality in the home. Moving dirty air through the HVAC system means breathing dirty air. But there is more to furnace maintenance than changing filters.
When scheduling a professional inspection, the homeowner should consider the following areas:
•Carbon monoxide – a professional will check the system for potential carbon monoxide leaks. A number of areas will be checked, but in particular, the technician will inspect the heat exchanger. This item transfers heat from the combustion chamber to the air circulated through the furnace. A crack in the combustion chamber wall can leak carbon monoxide in the circulated air;
•Inspect and repair the blower as needed. The blower is the fan in a forced air furnace and most responsible for circulating air through the HVAC system. Blower fins will be inspected and cleaned and the fan motor oiled as necessary. The blower control will be adjusted if needed;
•Electrical components on the furnace will be checked and connectors should be cleaned if needed. This includes pilot controls, voltage reducers and the thermostat;
•The gas supply orifice should be checked and cleaned. This item supplies gas to the combustion chamber. A plugged orifice is not only inefficient; it can be a safety hazard. The flame will be checked and adjusted as needed;
•Supply lines will be checked for signs of leaks. Even a small gas leak is a dangerous situation and may go unnoticed. Technicians will ensure any leaks are properly sealed;
•The furnace will be checked for proper air flow, both into the combustion chamber and through the ventilation system.
Annual maintenance by a trained professional can not only save energy costs, it can extend the life of the furnace. Small areas of furnace repair, when done promptly will prevent larger repairs in the future. And most importantly, maintenance ensures the system operates safely.