Frequently Asked Questions About Raleigh Home HVAC Systems
Below are some of the most common questions homeowners ask about heating and air conditioning systems.
AYou may wish to consider replacing your air conditioning or heating system if it is old, inefficient or in need of repair. Today’s systems are as much as 60% more efficient than those systems manufactured as little as ten years ago. In addition, if not properly maintained, wear and tear on a system can reduce the actual or realized efficiency of the system. If you are concerned about utility bills or are faced with an expensive repair, you may want to consider replacing your system rather than enduring another costly season or paying to replace an expensive component. The utility cost savings of a new unit may provide an attractive return on your investment. If you plan on financing the purchase, the monthly savings on your utility bill should be considered when determining the actual monthly cost of replacing a system. The offsetting savings may permit you to purchase a more efficient system.
Tuning up the distribution side of a forced-air system starts with the blower. The axle should be lubricated, blades cleaned and lower motor checked to insure the unit isn’t being overloaded. The fan belt should be adjusted so it deflects no more than an inch when pressed. Every accessible joint in the ductwork should be sealed with mastic or UL-approved duct tapes. Any ducts that run outside the heated space should be insulated. On a hot-water system, the expansion tank should be drained, the circulating pump cleaned and lubricated and air bled out of the radiators.
While thermostats rarely fail outright, they can degrade over time as mechanical parts stick or lose their calibration. Older units will send faulty signals if they’ve been knocked out of level or have dirty switches. To re-calibrate an older unit, use a wrench to adjust the nut on the back of the mercury switch until it turns the system on and, using a room thermometer, set it to the correct temperature. Modern electronic thermostats, sealed at the factory to keep out dust and grime, rarely need adjusting. However, whether your thermostat is old or young, the hole where the thermostat wire comes through the wall needs to be caulked, or a draft could trick it into thinking the room is warmer or colder than it really is.
A neglected in-duct humidifier can breed mildew and bacteria, not to mention add too much moisture to a house. A common mistake with humidifiers is leaving them on after the heating season ends. Don’t forget to pull the plug, shut the water valve and drain the unit. A unit with a water reservoir should be drained and cleaned with white vinegar, a mix of one part chlorine bleach to eight parts water or muriatic acid. Mist-type humidifiers also require regular cleaning to remove mineral deposits.