RV Air Conditioner Repair and Troubleshooting Guide

One of the best aspects of RVing is the ability to bring the comforts of home on the road with you – with one of the main comforts being air conditioning!

Unfortunately, there will come a time when that comfort breaks down. And let me tell you, your AC never breaks down at a convenient time.

Our RV air conditioner repair and troubleshooting guide below covers some of the most common AC issues and tips to repair them. This will help you save time and money you can spend on the road!

RV Air Conditioner Repair & Troubleshooting Guide

Even the best RV air conditioner will eventually run into problems. And when it does, there are five main issues you will run into:

1. The air conditioner has no power and won’t turn on
2. It will turn on but won’t run
3. It runs but isn’t blowing cold air
4. The air conditioner cycles on and off
5. It’s noisy (or making an odd noise)

If you’re experiencing one of these five issues, jump down to the appropriate section below for tips to repair it.

Important: Before performing any repairs on your AC unit, be sure to turn the unit off and disconnect it from the power source to avoid electrical shock.

RV Air Conditioner Won’t Turn On

If your RV air conditioner is not receiving power and won’t turn on, it’s typically an issue with the power supply or the breakers.

Troubleshooting Tips

• Test the RVs power supply: Plug an appliance into a 110v outlet in the RV to see if it works. If it works, then the power coming into your vehicle is fine.
• Check the breakers: If your RV is receiving power, next, we need to check the breakers. It’s not uncommon for a breaker to trip in the RV and cause the AC to stop working.
• Check the transfer switch: If your unit powers on with shore power but not while using a generator, it could be a bad transfer switch.

If everything checks out, it’s time to call a qualified professional to service your air conditioner.

Tip: Find a mobile RV repair service near you to get your AC running again!

My RV Air Conditioner Won’t Run

If your RV air conditioner powers on but will not run, it’s typically an issue within the unit itself.

Troubleshooting Tips

• Check the fault codes (if applicable). Many RV air conditioner models, for example, the Dometic Brisk 2, will display a fault code on the unit when there is an issue. Check your owner’s manual for the meaning of the code.
• Check the high-pressure switch circuit. If your AC model has a high-pressure switch safety circuit, it could have been tripped due to abnormal conditions (dirty filters, etc.). Refer to your owner’s manual for steps to reset the circuit. In some models, it’s as easy as turning the RV’s power supply off and back on.
• Check the capacitors. Your RV air conditioner unit typically has two capacitors – a run capacitor and a start capacitor. Often when you hear a humming sound but your fan won’t kick on, it’s due to a bad capacitor. You can test your capacitors using a standard multimeter. If you find a bad one, you will need to contact the manufacturer for a new one or find a suitable replacement.
• Check the thermostat. This may seem like a no-brainer, but make sure the temperature on the thermostat is low enough for the unit to kick on.

If all the above checks out, you will need to contact a qualified service technician to service the unit.

My RV AC is Not Blowing Cold Air

If your RV air conditioner turns on but isn’t blowing cold air, it typically needs proper maintenance performed on it, or it simply can’t keep up.

Troubleshooting Tips

• Check the Thermostat: The first thing to do is to ensure that your thermostat is set to the right temperature and is in the ‘cool’ mode.
• Check the outside temperature: On extremely hot days, it can be difficult for your RV AC to keep up, especially if your RV has a high heat gain. If your vehicle is poorly insulated, has a lot of windows, is located directly in the sun, and so on, it can be difficult for even the best air conditioner to keep the vehicle cool. Try parking your RV in the shade, keep doors and windows shut, and don’t use heat-producing indoor appliances like your stove to help keep your RV cool.
• Check the air conditioner filters: A dirty air filter can restrict airflow and cause the air conditioner to not cool properly. Checking and cleaning the filters every two weeks will help keep your AC blowing cold air.
• Inspect the condenser and evaporator coils: Dirty condenser and evaporator coils are another common culprit of air conditioners not blowing cold air as they should. They can also lead to your high-pressure switch circuit tripping. Check out this video on how to clean your RV air conditioner coils.

• Check the refrigerant levels: Low refrigerant levels in the compressor are another common cause for your AC not blowing cold air, though, in our experience, it’s rarely the culprit. How you check the refrigerant level will depend on the model you have (if you are even able to). And while you might be able to check the levels and even recharge the air conditioner yourself, I recommend you leave this to a qualified technician. They will be able to identify why your refrigerant levels are low and will be sure to discard the old freon responsibly (hopefully).
• Examine the Air Ducts: If the air ducts are blocked or leaking, they can cause the air conditioner to not cool properly. If your RV has a ducted system, inspect them for any blockages or leaks.
• Is your AC unit old? Let’s face it, nothing lasts forever. The older your AC gets, the more of a chance it won’t be able to keep up with the high demand of keeping your RV cool. So, it may be time to invest in a new unit for your RV.

RV Air Conditioner Cycles on and Off

If your RV air conditioner is cycling on and off frequently, this is a common issue known as short cycling. It can lead to inefficiency, increased wear on the air conditioner components, and inadequate cooling.

Here are some troubleshooting steps to help you address this issue.

• Check the Thermostat Settings: The first step in troubleshooting this issue is to check your thermostat settings. Ensure that the thermostat is set to the correct temperature and mode. If the settings are too close to the current room temperature, it may cause the unit to cycle on and off frequently.
• Check for Frozen Evaporator Coils: Frozen evaporator coils can cause your air conditioner to cycle on and off frequently. When the coils freeze, the air conditioner may become inefficient and start to short cycle. This is often due to insufficient airflow from issues like a dirty air filter or blocked vents. If you see ice buildup on the coils, turn off the air conditioner to allow the ice to melt.
• Check for Refrigerant Leaks: Low refrigerant levels can cause the air conditioner to cycle on and off frequently. If you suspect a refrigerant leak, you’ll need to have a professional inspect the system and refill the refrigerant if necessary.
• Evaluate the Size of Your Air Conditioner: If your air conditioner is too large for your RV, it may cool the space quickly and then shut off, only to turn back on when the temperature rises again. This is a more complex issue that may require professional evaluation and potentially replacing the unit with one that is appropriately sized.

If you’ve gone through these steps and the problem persists, it’s time to seek professional help. An HVAC professional can diagnose and fix more complex issues that may be causing your air conditioner to cycle on and off.

RV Air Conditioner is Noisy

A noisy RV air conditioner can be a nuisance, especially when you’re trying to enjoy a peaceful trip. The noise can be a sign of various issues, from minor to more serious ones.

Here are some steps to troubleshoot and potentially quiet down your noisy RV air conditioner.

Step 1: Identify the Type of Noise

The first step in troubleshooting a noisy air conditioner is to identify the type of noise. Is it a rattling, buzzing, humming, or whistling noise? The type of noise can give you clues about the potential issue.

Step 2: Check for Loose Parts

A common cause of noise in an air conditioner is loose parts. This could be anything from the screws that hold the unit together to internal components. Tighten any loose screws and check the fan blades for any signs of looseness or damage.

Step 3: Inspect the Fan

A noisy fan can cause your air conditioner to make a lot of noise. Check the fan for any signs of damage, such as bent blades. If the fan is damaged, it may need to be replaced.

Step 4: Check the Compressor

The compressor is another component that can cause noise when it’s not working properly. If the noise is a buzzing or humming sound, it could be a sign of a compressor issue. A professional may need to inspect the compressor to determine if it’s the source of the noise.

Tip: If you’ve gone through these steps and the noise persists, it’s time to seek professional help. An HVAC professional can diagnose and fix more complex issues that may be causing the noise.

Remember, regular maintenance of your RV air conditioner can prevent many common issues, including noise. Regular cleaning of the filters and coils, checking for loose parts, and ensuring the unit is working properly can all contribute to a quieter and more efficient air conditioner.

Regular RV AC Maintenance Tips

Maintaining your RV air conditioner is crucial for its longevity and efficient operation. Regular maintenance can prevent common issues, enhance performance, and extend the unit’s lifespan.

Here are some expert tips on how to maintain your RV air conditioner:

Important: Before performing any maintenance on your AC unit, turn the unit off and disconnect it from the power source to avoid electrical shock.

Clean the Air Filters

Be sure to clean the air filter(s) in your RV AC after every two weeks of operation. Check out our guide on how to clean an RV air conditioner filter for the exact step-by-step process.

Important: Do NOT run your AC without the filter in place! This can cause the evaporator to become clogged with dust and reduce performance.

Clean AC Box Housing

Clean the air distribution box housing and the control panel regularly with mild soap and a soft cloth.

Important: Do NOT use an abrasive scouring pad or furniture polish to clean the housing or control panel.

Inspect for Leaks

Leaks can lead to various problems, from reduced efficiency to potential water damage in your RV. Regularly inspect your air conditioner for signs of leaks, paying particular attention to the condenser coils and the gasket that seals the unit to your RV’s roof.

Keep Your RV AC Covered When Not in Use

There are days, even months, when the RV air conditioner isn’t running. During this time, it’s easy to accumulate soot and dirt in the air conditioner, which can cause a host of issues. By investing in a good A/C cover, you can keep a lot of that debris out, thus keeping the unit clean.

Tip: While on your roof, check any seals and tighten any screws or bolts as needed. This will help ensure a tight seal to prevent leaks and help keep your RV AC quiet when operating.

Inspect the Condenser & Evaporator Coils

At least once a year, inspect the air conditioner condenser and evaporator coils. Look for coils that have been blocked by dirt or leaves. This is especially important if you start to notice your AC not blowing as cold of air as it used to. Check out our video above on how to properly clean these coils.

Lubricate the Fan Motor

Some units may require you to lubricate the blower motor periodically. Check the owner’s manual to see if this is necessary and for the type of oil needed. SAE 20 non-detergent type oil is most commonly used and can be found at a heating and cooling parts supplier.

Regular Professional Service

While many maintenance tasks can be performed on your own, it’s a good idea to have your air conditioner professionally serviced at least once a year. A professional can perform a thorough inspection and address any potential issues before they become significant problems.

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