RV AC Thermostat Troubleshooting [7 Solutions To Common Problems]

If you have an RV, you know how important it is to keep your AC in good condition. RV AC Thermostat Troubleshooting will help you find and fix any issues with your RV AC.

Traveling from site to site in an RV can be an incredible adventure – if you aren’t frying the whole time. 

Whether your RV has tons of amenities or is more pared-back, the fact is that it is still a big metal rectangular tub, which means that it traps heat to an incredible degree. There is a reason that you aren’t supposed to leave pets or small children in cars, trucks, or RVs on hot days – the interior can feel like an oven.

One of the few things standing between you and a frying hot experience is your RV’s AC system. If that breaks down, you could be stuck with triple-digit heat in your RV for hours on end, which is neither comfortable nor healthy. At the same time, if your thermostat breaks down, you’ll be left without a way of telling how hot it is in your RV. Your thermostat can also be responsible for helping switch on your AC at certain degrees, so if it’s broken, depending on your AC system, it may not turn on at all.

That’s obviously not acceptable. Thankfully, these tips can help you identify and fix common problems with your AC and thermostat.

RV AC Thermostat Troubleshooting

RV AC Thermostat Troubleshooting

1. A Lack of Power

The first big red flag that might tip you off to thermostat problems is if it loses power and simply refuses to turn on. In cases such as this, the most likely culprit is a bad or blown connection within the electrical circuitry. The wiring may also have come loose during your last trip.

The consequence of this should be obvious. If your thermostat doesn’t turn on and you notice the temperature in your RV is too hot, it won’t be able to activate your AC and cool it down.

Another potential warning sign here is if the light on your thermostat is dim or not turning on at all.

If your thermostat is powered by a battery rather than by being plugged into an electrical outlet in your RV, you might simply need to replace the batteries. On the other hand, if you do this and your thermostat still doesn’t function properly, it may be a problem with the unit overall and, thus, need to be replaced.

2. The Heater or AC Won’t Turn on or Off

At the opposite end of the spectrum from AC and thermostats that refuse to turn on are units that don’t turn off when you want them to, which is obviously a major problem in itself. You’d be surprised how, even on a hot day, an RV can quickly start to feel like an icebox if you allow the air conditioning to run continuously for hours on end. Even if that doesn’t happen, this is obviously a major drain on your power, and can, thus, burn out the batteries quickly or drain power from the rest of the RV.

Potential causes here include frayed wiring and improper calibration. If this is the case, you’ll need to remove the unit before checking the wiring and replacing any damaged wires you might find. You may also want to consider calling an electrician and having them inspect your RV’s electrical system.

The opposite of the issue above, this nevertheless has the same likely root cause – wiring, electrical, or battery problems. You’ll, thus, want to perform all the same checks of these things as you would if you have a heater that won’t turn off. As with the above issue, you’ll need to either repair or replace the wiring or batteries yourself or else take the unit to be inspected by electrical professionals.

3. Discrepancies Between the Settings and Temperature

One of the reasons your thermostat is so important is that it is essential for telling you what the temperature is inside your RV. This, in turn, is important for activating automated presets for when your heating or AC system should turn on.

However, if there is a discrepancy between what your thermostat shows and what the temperature actually is, this whole process will be thrown off. When you turn the heat or the AC on, the temperature on your thermostat should lower or rise correspondingly. If it does not, you probably need to recalibrate the thermostat or replace it entirely.

That said, there are other reasons why your thermostat may not be reflecting the temperature it should be. You may have simply accidentally set it for the wrong temperature. Before taking any more drastic measures, be sure to check to make sure that you have set your thermostat for the correct setting.

Likewise, if your thermostat is running continuously, you should make sure you haven’t accidentally left it on or left it on auto mode, which is activating at the temperatures for which you have preset it.

If that doesn’t do the trick, consider turning your thermostat down a few degrees.

You might also want to consider turning your thermostat up or down by a few degrees to see if that results in more amenable results. In summer, it’s typically a good idea to set the thermostat five degrees or so below the temperature outside so as to ensure that it turns on before it gets too hot. Conversely, you should set it five degrees above the temperature outside when taking your RV out in the winter for the same reason visa vi your heater.

4. Air Blast Your Thermostat

Sometimes, dust or other pollutants can get into a thermostat and prevent it from working properly. If you suspect that might be the case with your unit, you’ll want to blast the dust out of there using a can of compressed air. That said, you should be careful when doing this since you don’t want to accidentally dislodge anything.

RV AC Thermostat Troubleshooting

Thermostat Problems with Your AC or Heater

Besides your thermostat simply not turning on or functioning properly, it could also be a harbinger of something being wrong with your AC or heater.

1. The AC Isn’t Blowing Cold Air

Related to the thermostat issue above, if your AC isn’t blowing cold air, it could be that you have an electrical issue or that the unit is not properly calibrated to register the temperature as being hot enough to activate. However, if the unit hasn’t shut off but is simply blowing hot rather than cold air in your face, it could be a sign that the coils are dirty or that the fans have started to break down. Dirt and debris can become lodged between the fins of the fan, causing it to operate poorly.

If this is the case, you’ll once again want to look into blowing it clean with compressed air.

Alternatively, it could mean that there is an issue with the coolant that the unit uses to blow cool air. If that’s the case, you’ll need to repair or replace this.

2. Noisy Air Conditioners

This likely isn’t related to your thermostat, but it’s still a common issue with AC units in RVs.

If your AC has started to become particularly loud, you’ll want to check to see if anything has become loose. If you hear a rattling sound, this is likely the cause of the situation and something you’ll want to address immediately. Open up the unit, identify the thing that has popped loose, and reattach or remove it.

Alternatively, loud sounds emanating from your AC may be a sign that it is starting to wear out. If you have experienced repeated problems with your AC and thermostat, it may be a sign that the two are simply reaching the end of their tether and it’s time for a replacement.

3. Foul Smell

This nose-wrinkling issue is another potential consequence of your thermostat or AC breaking down. If the two are starting to burn out or have collected lots of dust and dirt on them, they can start to smell. Alternatively, if they are near your bathroom and you have a plumbing issue, you may wind up with the oh-so-lovely aroma of bathroom sewage and “leavings” permeating your RV.

To combat these issues, you’ll want to check to see if any pipes are leaking or AC or thermostat filters have broken down. If so, you’ll need to repair or replace the offending item.

RV AC Thermostat Troubleshooting Final Thoughts

From foul-smelling filters to running hot or cold or thermostats simply refusing to work, there is any number of reasons why any of these issues may arise in your RV. Given the interconnected nature of RV systems, you may have multiple issues at once.

Through RV AC thermostat troubleshooting you’ll find that the most common issues tend to be electrical, due to dust and dirt buildup, or issues with your settings.

You should check each of these potential causes before moving on to more drastic measures such as rewiring things or getting them repaired.

A little bit of attentiveness to these issues can go a long way toward resolving them and getting your RV’s thermostat and AC working again.

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