It’s mid summer. It’s too hot to go outside and do any work, plus you are on vacation anyway. Inside, the air is moving and remaining cool, but it won’t stay on for long enough to cool to your liking. There might be a problem.
Having an RV with air conditioning is great when it works, which is most of the time. RV owners have a nice, private place to stay with control over just how much AC they want. AC units can have issues, including turning on and off repeatedly.
Your RV air conditioner turning off and on repeatedly can be really annoying. The problem could be a variety of things, including mechanical defects in the air conditioner. The problem could also be in your thermostat.
Your RV air conditioner’s thermostat
You have probably seen and experienced a thermostat, but we will give you the rundown. The thermostat is often attached to the wall in your RV. The thermostat measures the air temperature in the RV and sends a signal using wires that lead up to the air conditioner, telling it to turn on or off.
A normal working thermostat allows you to set the temperature you want for your RV, and keeps the air conditioner running until the RV air temperature reaches the desired temperature.
The process of turning the AC off before the desired temperature is reached is called “short cycling”.
The thermostat itself can cause short cycling. The thermostat can get miscalibrated and send the signal to stop and start your AC at the wrong times, leading to the incorrect temperatures, Another symptom of a thermostat issue is your air conditioner not turning on at all when RV air temperature is not the same as you asked of your thermostat.
The RV thermostat is the easiest thing to fix. In many cases, you can just replace it by disconnecting the old one from the wall. You might want to keep track of where the cords and wires go! Take a picture if it helps.
Installing a new thermostat involves doing the same process but backwards. This might fix short cycling.
Cleaning your air filter for your AC
Most air conditioners have an air filter, either in the unit or within the opening of the duct work in your RV.
If this air filters gets too badly clogged, the result can be an overheating air conditioner. An overheated air conditioner will shut down in an effort to cool down and attempt to turn on again later.
Consult your RV manual to find your air filter. Remove the air filter and either clean it or replace it. If you find that your air filter is especially dirty, this could be the cause of your problem.
Cleaning your RV air filter is often as simple soaking it in water for about 30 minutes then letting it dry. Another option is to just vacuum it out.
Loose connections
Having loose connections between your thermostat or power source and your air conditioner can lead to weird results. The air condtiioner can be inconsistently timed and stop at random.
A loose connection often results in either the compressor or fan not getting enough power at some point during the cooling cycling.
If you are going to check your air conditioner for loose wiring, we certainly suggest shutting off the power source to your air conditioner first. Otherwise, consult a professional to find issues.
Loose connections are a bit tougher to diagnose without much experience, but can also be dangerous. Electricity will attempt to jump from the carrying wire to metal objects in a process known as “arcing.” Arcing can cause the air conditioner to get seriously hot and potentially catch on fire if the circuit is not broken.
Evaporator Coils
The evaporator coils in your air conditioner unit can get overwhelmed by moisture if you turn your air conditioner on during cooler weather or when it’s especially humid outside. It’s possible for them to get too cold.
Shutting down your air conditioner and allowing the coils to thaw is a good first step. If the problem persists, consider getting some professional help to understand why the coils keep freezing.
One thing to help is to disconnect the power from your air conditioner as well as the battery. Vacuum out debris, dust, and anything else foreign near the evaporator coils that could keep them from breathing properly.
Incorrect Thermostat Settings
You may have set your thermostat incorrectly and don’t even know! Many thermostats have a fan function and an air conditioner or furnace function. Turning the fan on and leaving it on keeps air circulating. Leaving either the furnace or air conditioner off means that the air isn’t warm or cool.
We bring this up because having the fan on without any actual air coming in can make it seem like the air conditioner is turning on and off, when it was never on.
Since this is the easiest fix, we suggest just making sure that your thermostat is set to having either the furnace or the air conditioner on instead of just the fan.
Conclusion
We’ve introduced a variety of reasons why your air conditioner might be “short cycling.” The reasons could be simple maintenance problems or issues with the wiring within your air conditioner. Knowing exactly why your air conditioner keeps stopping and starting might not be especially easy, but you can start with the most simple issues first.
We suggest doing some of the maintenance things suggested while working on your air conditioner. Preventing maintenance is a great tool to use to avoid issues in the future.
Otherwise, getting a good understanding of how the thermostat works will also help you better control your air conditioner in the future.