Why Is My Air Conditioner Short Cycling?
You can identify AC short cycling from the air conditioning unit, turning itself on and off constantly. If you notice this occurring, it is important to address air conditioner short cycling problems as they can lead to complete AC unit failure.
Air conditioner short cycling can be resolved with help from an HVAC professional. To help prevent short cycling and costly repairs, the Comfort Specialists at ARS/Rescue Rooter have put together this guide to help homeowners.
What Is Short-Cycling?
Short cycling is the term used when the cooling cycle on an air conditioning unit is shorter than it should be. On a hot day, this will typically last 10 minutes and then stop for 10 minutes, and so on. On cooler days, the breaks will be longer. However, AC short cycling disturbs this pattern.
The cooling cycle refers to the entire process of the AC unit compressing and circulating the refrigerant through the condenser and other parts of the AC system. When the cycle is short, the compressor turns on and off more than it should, causing excess stress on the compressor that increases wear and tear on the entire system.
AC short cycling not only damages the air conditioning system but also prevents it from working efficiently and properly cooling your house.
What Causes an AC to Short-Cycle?
Air conditioner short cycling is usually a symptom of a problem, and there can be a variety of possible causes.
The best way to prevent it is through air conditioner maintenance from an HVAC professional.
Clogged Air Filter
The air conditioner relies on airflow to function properly. Clogged air filters restrict airflow and cause strain on the unit. A dirty and dusty air filter can lead to several air conditioning issues and is often the first place an HVAC professional will look when providing service.
It can lead to short cycling problems when heat can't escape the HVAC system and cool air can't get in, tricking the system into thinking it is hotter indoors than it really is. Therefore, the air conditioner turns on more often without successfully cooling the home.
Clogged filters not only lead to HVAC and short cycling issues but uses more energy consumption and will cause higher energy bills.
Generally, a professional HVAC technician will recommend changing filters every three months. However, if you live in a particularly dusty and dry climate or have pets, it may be better to replace the filters more frequently.
Another reason air conditioners short cycle is low refrigerant levels. Refrigerant is the chemical that cycles through your air conditioning system. It removes heat from inside the house and releases it outdoors.
Refrigerant should remain at a set level, known as the charge. If the charge level is low, contact a professional to add more refrigerant and address the cause of the reduced amount.
Without the proper charge of refrigerant, the air conditioner unit will have to work harder, which leads to overheating and short cycling.
A failing air conditioner compressor may start to short cycle if it's unable to stay on for a longer period of time. Short cycles will only further damage the compressor, so it is important to have an HVAC professional check it as soon as possible.
If the compressor needs to be replaced, be sure to check for a manufactures warranty.
Oversized Unit or Undersized Unit
A common cause of AC short cycling issues is an improperly sized air conditioner. It will be difficult to maintain the proper time of cooling with oversized units.
An oversized air conditioner will cool the area and shut off in a short period of time, reducing the length of the full cooling cycle.
Unfortunately, there is no way to fix this, and you will need to replace the AC unit with one of the proper size.
A miscalibrated thermostat will incorrectly gauge the specific temperature causing the HVAC unit to turn on and off at incorrect times.
The system will turn off prematurely and then quickly turn back on in an attempt to reach the set temperature. The thermostat will incorrectly tell the unit that the set temperature was reached or vice versa.
A miscalibrated thermostat puts lots of strain on the HVAC system and can be a difficult problem to notice. It's beneficial to have your AC thermostat in a central location, not too close to vents, to ensure accurate readings.
Iced or Dirty Evaporator Coil
A frozen or dirty evaporator coil can also lead to AC short cycling. The evaporator coils remove latent heat from your house, and when iced or dirty, they can malfunction, leading the AC system to overheat and potentially short cycle.
Evaporator coils can be an easy fix and are usually the result of poor maintenance. Schedule service with a professional if the AC evaporator coils appear to be frozen or dirty.
Failing Low-Pressure Control Switch
If the air conditioning system operates at a lower pressure than normal, it can freeze up. First, this affects the evaporator coil and then eventually the compressor.
If your air conditioner's short cycling problems are not solved by fixing the evaporator coils, the filters, or the refrigerant levels, this could be the root cause.
You should have an HVAC professional replace the low-pressure control switch with a brand new one.
Leaking Air Ducts
Leaking ducts will pull air inside from the outside, the basement, and inside your walls. This leads to the air conditioning system working hard to try and regular the indoor temperature.
They not only lead to air conditioner short cycling but also cause higher energy bills and excessive dust.
Frequently Asked Questions
How do I stop my AC from short cycling?
Check out the above listed items, starting with the filters. Then, contact a professional HVAC technician to diagnose and repair the air conditioner.
What would cause an AC to short cycle?
Clogged filters, low refrigerant charge, frozen evaporator coils, or an oversized air conditioner unit could cause air conditioner short cycling.
What is short cycling on an AC unit?
Short cycling is when an air conditioner turns on and off frequently in a short time.
Should I turn my AC off if it is short cycling?
No, this is not necessary unless the evaporator coils are frozen, in which case, turn off your air conditioner to let the coils thaw.
Need AC Repair Service Fast? Call ARS/Rescue Rooter
ARS/Rescue Rooter is providing expert service for all your air conditioner, heating, plumbing, and electrical needs. We prioritize customer service and complete your job quickly without compromising excellent workmanship.
You can trust our team to arrive on time and fix your air conditioner or heating system as soon as possible. Find your nearest ARS/Rescue Rooter location or book an appointment online to schedule your service today.