Not normally because those safety switches must be reset manually so it would only cycle off once and not come back on. Most common cause I've found is heat anticipater set for too short of cycles, like David said. Happened to me, the rain cap collapsed above the roof on one house and the insulation on the equipment panel came loose and lodged against the blower....both cause short cycling. The actual meaning of short cycle in the trade means that the furnace is turning on then off in a very short time frame from what might be normal due to current weather conditions. The determination is it normal or abnormal, on very cold night a short cycle could actually be normal as the house is loosing heat on a very accelerated level. Abnormal cycling can be cause by lack of air flow from dirty evaporator coil, dirty air filter, dirty blower wheel and I have even seen the blower running backwards, too many supply�s closed, returns blocked off. Any or all or the above are very common, less common would be an oversized unit.

Short cycle may also be caused by a component failure, depending on the age of the unit modern units are loaded with things that can fail, 20 year old units no so many things. Example would be inducer motor proving switch defective, inducer motor not spinning to speed all the time, circuit board failure etc. The thermostat heat anticipator too can cause this, they are best set using a heat anticipator meter, no guideline is correct since the length of the thermostat wire, the volt amps of the control transformer etc determine this. The stamped number on some furnaces is usually incorrect. But set incorrectly the furnace will short cycle. Most better digital stats will allow for anticipator adjustments, many cheaper ones will not and are pre set, how these are set is normally in the installation guide. The purpose of the heat anticipator is to turn the heating unit off just prior to the house reaching the desired temperature, allowing the furnace to cool down with out over heating the house beyond the set point.

Gas , oil and electric furnaces use them, heat pumps do not. Solitaire Heating & Coolinglow wattage ac unit CSG Training (HVAC Training & Consulting)ac outside unit not spinningWhen an air conditioner cycles on and off in rapid succession, it’s a problem called short cycling. seasons 4 air handling unitAnd it’s a big deal -- short cycling not only harms the energy efficiency of your home’s largest energy-consuming appliance, it puts excess wear on your equipment, leading to more frequent breakdowns and repairs. Short cycling can be caused by a variety of factors, and they all need to be corrected as quickly as possible to minimize the expense and save your equipment. One of the most common causes of air conditioner short cycling is an air conditioner that is too big and powerful for the space it’s designed to cool.

This is occasionally a mistake made with good intentions -- bigger air conditioners cool down spaces faster, and since no one likes to wait for a hot room to cool down, bigger must be better, right?Oversized units cool down homes so quickly that they can’t properly dehumidify the air. This leads to rooms feeling damp and clammy. It also causes greater fluctuations in temperature, creating spaces that alternately feel too hot or too cold. And all the while, the unit is cycling on and off rapidly, wearing down the motor and other components. There are other problems that can crop up at any time and cause a short cycling issue: Ice buildup on the evaporator coils. This problem can have its own causes -- airflow problems and refrigerant issues chief among them -- but iced-over coils can easily lead to short cycling. A knowledgeable HVAC technician should diagnose this issue.When there’s insufficient air flow through your system, it has to work harder. If it works too hard, it could overheat and shut off automatically.

When there’s an extreme air clog, short cycling is one possible result. Refrigerant loss or leak. Low refrigerant can also cause short cycling by overheating the condenser. This should always be investigated by an HVAC expert, because any leak will need to be detected and repaired.Sometimes the issue isn’t with the air conditioner at all, but rather with a malfunctioning thermostat. Refer to your thermostat owner’s manual for troubleshooting tips, or call an HVAC professional to test for problems. Pay close attention to your air conditioner’s cooling cycles, and if you notice signs of short cycling, don’t wait to address the issue. Your energy and repair bills will just continue to rise until your local HVAC experts can diagnose and fix the problem!R&R Heating & Air Conditioning Blog "Our Ruud 2.5 ton heat pump quit cooling this afternoon. The fan on the outdoor unit run but inside the house it sounds like a fan is short cycling . . . on and off. Setting the thermostat to heat does not work either.

There could be a few things going on. Have you changed your furnace filter lately? It sounds like the furnace fan is lacking air or the blower motor maybe dirty and or over heating if it is coming on and off. Check the furnace filter, turn off all power and pull blower assembly and clean with a shop vac. See if you can turn the fan freely by hand. If not the bearings maybe going out and the motor just needs to be replaced. If that doesn't work please contact us for a service call and we will take care of you asap. Thanks for your question and good luck! Do you have a question?Optimal humidity levels to feel the most comfortable indoors are ~30-50%. Maintaining these humidity levels in your home or business not only has health benefits, it can greatly enhance the comfort level for your family and team members, as well as save energy and reduce maintenance costs. Humidity is the amount of water vapor in the air. You have probably heard the term relative humidity while listening to the weather report.

Relative humidity is the term we most often use to define the amount of water vapor in the air at a specific temperature. When the air is warmer outside, it retains more water vapor, and when the air is colder outside, the air does not retain as much water vapor. This is the reason why the summer months are so humid and the winter months are so dry. Do you ever wonder why you feel so hot and sticky in the summer? You feel hot and sticky in the summer because the high level of humidity in the air slows down the cooling process of evaporation from the human body. The body’s method of cooling itself is by releasing moisture through sweat glands (sweating)…the sweat then evaporates into the air and provides a cooling effect for the body. The sweating process is slowed when the humidity is very high because the air is already saturated with water. When the air is already saturated with water, the air cannot absorb the sweat from the body, and in turn, the evaporation process is slowed down, thus reducing the cooling sensation.

Although no one can control the amount of humidity outside, the good news is, humidity can be controlled indoors to reduce or eliminate the hot and sticky feeling. How is humidity removed from indoors? One of the most popular methods is air conditioning. As the air conditioner runs, it pulls the moisture out of the air as the air passes over the indoor coil. Another method is using a dehumidifier that can either be stand alone or connected to the ductwork. Adding an Energy Recovery Ventilator (ERV) can help push limited amounts of moisture outside but ERV’s are more geared toward bringing in fresh air and expelling stale air from indoors rather than dehumidifying the air. I have an air conditioner but it is still very humid inside…why? Your air conditioner or heat pump may be oversized or if it is single speed, it may not be running long enough cycles. When your air conditioner or heat pump is oversized, it turns on and off in short spurts, which is referred to as short cycling.

When an air conditioner or heat pump short cycles, it brings down the temperature rapidly, however the cycles do not run long enough to dehumidify. Bigger is not better in air conditioning! If you have a single speed air conditioner or heat pump, it may not be running long enough when the temperatures are relatively mild. Air conditioning capacities are determined by a calculation that takes into account the average hottest temperature in the cooling season. While this calculation takes into account the hottest average days, there are only a handful of those days a year when the temperature reaches those extremes. Plus, those extreme temperatures are generally reached only between 3:00 P.M. to 8:00 P.M. As a result, a single speed air conditioner or heat pump is more than likely oversized for the other 19 hours of the day so it will not run long enough to effectively dehumidify. How can I reduce the humidity indoors? This is a question posed to us on a regular basis. Over the years, manufacturers of air conditioning equipment have observed that managing humidity indoors has become even more essential.

As a result, manufacturers developed two-stage air conditioners and two-stage heat pumps. This was a huge step in the right direction to address indoor humidity, however, it didn’t fully solve the problem. Manufacturers now have perfected multi-speed units. With air conditioners now available in 5-speeds and heat pumps available up to 60-speeds, dehumidification and indoor comfort have reached unprecedented levels. Introducing multi-speed air conditioning into the equation allows the air conditioner to run longer cycles when outdoor temperatures are lower. In return, significantly more dehumidification can take place. These multi-speed units are also very efficient to operate. What are the effects of high humidity indoors? Optimal humidity for indoor comfort in the colder months is approximately30-45% and in the warmer months approximately 50%. The Center for Disease Control and Prevention (CDC) says that humidity should be kept at 50% or less to prevent the growth of mold.