Industry tips they do not want us to tell:
General HVAC Tips
1. FILTERS
One of the easiest maintenance tasks consumers can do themselves is maintaining the filters. Air filters should be inspected and cleaned once a month. This allows for regular monitoring to eventually determine when the filter needs to be replaced. Most filters can be changed every three months if no other problems exist. Maintaining clean and regularly changed filters will not only produce better air quality, but appliances will function more efficiently, which can save on heating and cooling costs.
2. Clean Coil
An air conditioner that does not seem to effectively cool a room may be hindered by a dirty evaporator coil. Simply removing the front panel of the unit, locating the coil and gently cleaning the coil with a dry cloth or small brush may remedy the issue. It is important to ensure that the coil is dry before proceeding.
The condenser fan is another important HVAC element that must be maintained. Condenser fans that contain oil ports should be lubricated at least annually. The outside condenser should also be shielded from direct sunlight if possible. Keeping vegetation at least two feet away from outdoor HVAC units will also promote higher performance and potentially lower energy bills due to higher efficiency. The further away vegetation is, the better an HVAC unit will operate.
Air to Air Exchangers
Routine maintenance involves replacing or cleaning the filters if so equipped, and keeping the outside air intake free of debris. After years of service the air exchanger will become crusted with grease and dirt that collects during condensation. Removing this accumulation will probably take solvents or degreasers and require opening up the cabinet and compartments.
Condensers
The coil is usually made of copper tubing with aluminum fins, but some manufacturers use aluminum tubing. Its purpose is to transfer heat as rapidly as possible. Pressure inside the coil can exceed 400 psi. during extremely warm weather conditions. The cleaner it is kept, the better it transfers heat. Rinsing with a garden hose occasionally when the unit is not running will help keep it operating efficiently. After many years of use it may be necessary to put special chemicals on to clean it.
The condenser fan moves air across the coil to increase the transfer of heat. It is critical to the system. Obstructing the flow of air will not only reduce efficiency, but can lead to compressor failure. Keep debris and objects away from the coil and fan to allow maximum air flow. Some condenser fan motors have sealed bearings, others need lubrication. Damage to the fan can occur if removed improperly. Have a qualified serviceman handle the lubricating if needed.
Humidifiers
Furnace mounted units can be by-pass, steam, mist, wick and powered. Some mount in the duct-work while others are attached to the plenums on the furnace. Whatever the model, mineral deposits from the water will reduce the effectiveness of the humidifier. Be sure to turn the water and humidistat off before servicing.
Special chemicals can be used to clean mineral deposits, but one of the safest is vinegar. A 50% mixture of vinegar and water will usually dissolve or help clean away deposits. If the humidifier has a drum with a belt, replacement of the belt at the beginning of the heating season can be the easiest fix if the water has a high mineral content. If the humidifier has screens or is the wick type, some corrosion can occur as well as build up
Heat pumps and electric furnaces usually have steam humidifiers to increase output. They are line voltage powered and must be unplugged or disconnected before servicing to avoid injury. With the exception of some mist type humidifiers, all have a reservoir. Stagnant water sitting in the reservoir during the off season can be a breeding ground for bacteria. Turn the water off and clean the humidifier if possible when heating season has ended.
Other than mineral deposits, the most common problem is sediment in the water supply. The float inlet valve has a tiny hole that easily clogs. The float is usually made of plastic, and if cracked will fill with water and sink. The valve will be stuck open and the reservoir will overflow. Use caution when scraping deposits off the float. If the deposits cannot be removed, replace the float or it will sink and cause an overflow.
Room Air Conditioners
Not obvious is the fact that they need maintenance routinely, just like any other machine. The filter, usually located behind the front grill, needs to be washed. The condenser coil at the back of the unit can accumulate a lot of debris, and might require a special chemical bath. All air conditioning systems, large or small, need good air flow across the evaporator coil and the condenser coil. Efficiency and performance drop rapidly as air flow decreases. Lose enough air flow and the unit will burn out. Rodents can nest inside when not in use, and can foul up the unit in many ways. Wasps and hornets, as well as the honey bee find finned coils to be comfortable nesting places. Nests and dead insects can ruin the air conditioner.
