Most RV Problems Are Appliance Problems
When something stops working on an RV, it's usually not the vehicle itself. It's the refrigerator that won't cool, the furnace that won't light, the water heater that's running but producing no hot water, or the air conditioner that's blowing but not cooling.
These problems feel mysterious because RV appliances are different from household appliances. They run on different power sources. They have different ignition systems. And the symptoms of a failed component often look identical to the symptoms of a simple settings issue or a tripped switch somewhere else in the system.
This guide walks through the most common RV appliance problems, what causes them, what you can check yourself, and when you need a professional. We've organized it by appliance so you can jump directly to the one giving you trouble.
RV Refrigerator
Symptom: Not Cooling or Not Cold Enough
RV refrigerators are absorption units — they work completely differently from the compressor refrigerators in your home. They use heat (from propane flame or an electric heating element) to drive a chemical cooling cycle. This means:
- They take 4–8 hours to reach operating temperature from warm
- They're sensitive to being level — more than 3 degrees off level and the cooling cycle is disrupted
- They don't cool as aggressively as residential units and won't recover quickly when loaded with warm food
Check first:
- Is the refrigerator level? Use a small level inside the unit. If the coach is even slightly off, move it.
- Are the roof vents clear? Absorption fridges vent heat upward through roof vents. Debris or a blocked vent stack will cause cooling failure.
- Is it set to AUTO mode? AUTO selects propane or electric based on availability. If you're plugged in and it's on propane-only, it may be struggling.
- Have you pre-cooled it? Never load a warm absorption fridge with warm food. Pre-cool empty for 4–6 hours first.
Likely causes requiring service: Failed heating element (electric mode not working), failed burner assembly (propane mode not lighting), failed thermistor, ammonia leak (yellow residue behind the fridge is a telltale sign).
Symptom: Propane Mode Won't Light or Keeps Clicking
If the fridge clicks repeatedly but won't light, or lights briefly and then shuts off:
- Check your propane supply — is the tank open? Is there propane in it?
- Check if other propane appliances work. If the stove lights but the fridge doesn't, the issue is specific to the fridge burner.
- The burner tube may be clogged with spider webs or debris — this is extremely common and a cleaning often fixes it
- The igniter may need cleaning or replacement
RV Furnace
Symptom: Won't Light or Blows Cold Air
RV furnaces run on propane and use a 12-volt blower motor. Both systems have to work for the furnace to operate.
Check first:
- Is propane on and is there gas in the tank?
- Is your 12V battery charged? A furnace blower pulls significant amperage. If your battery is weak, the blower may run but the ignition sequence won't complete.
- Check the furnace sail switch — the sail switch confirms the blower is moving air before allowing ignition. A stuck sail switch is a common failure point.
- Is the exhaust vent clear? RV furnaces vent outside the coach. A blocked vent will cause the furnace to lock out.
Common failure codes: Most RV furnaces (Dometic, Atwood/Lippert) have lockout sequences. If the furnace attempts ignition 3 times without lighting, it locks out. Cycling the thermostat off and back on resets it for another attempt. If it keeps locking out, the problem is real and needs diagnosis.
Likely causes requiring service: Failed sail switch, failed circuit board, failed igniter, failed limit switch (overheating protection), blocked flue.
Symptom: Runs But Doesn't Heat Adequately
If the furnace is running but the coach won't warm up, check for duct issues. Many RV furnace systems have flexible ducting that runs under the floor or through walls. A disconnected duct — which happens from travel vibration — dumps heat into a wall cavity instead of into the living space.
RV Water Heater
Symptom: No Hot Water
RV water heaters are 6- or 10-gallon units that run on propane, electric, or both. The most common issue is not actually a failure — it's that the bypass valve was left in winterization position.
Check first:
- Is the bypass valve in normal operating position? If you winterized your RV, there's a bypass valve (usually behind an access panel or under a cabinet) that diverts water around the water heater. It must be returned to normal position for the heater to fill and function.
- Is the water heater switched on? There's usually a switch at the tank and one at the main panel.
- Is it on propane or electric? Check that the appropriate power source is active.
- Has it had time to heat? A cold 6-gallon tank takes about 20–25 minutes on propane to reach temperature.
Symptom: Pilot Won't Light (Older Units)
Older Atwood and Suburban water heaters have standing pilots that need to be manually lit each season. Follow the manufacturer's lighting sequence exactly. If the pilot won't stay lit when you release the knob, the thermocouple has likely failed — a simple repair but one that involves working near a gas line.
Likely causes requiring service: Failed thermocouple, failed gas valve, failed heating element (electric mode), anode rod completely corroded (causes poor hot water quality and eventual tank damage).
RV Air Conditioner
Symptom: Running But Not Cooling
This is the most common summer complaint we get.
Check first:
- Are the filters clean? RV AC filters collect dust rapidly. A clogged filter reduces airflow to near zero. Clean or replace them before anything else.
- Is shore power adequate? RV air conditioners require 15–20 amps depending on the unit. If you're on a 30-amp hookup and running multiple appliances, the AC may be starved of power. If you're on a generator, is it a rated 3,000+ watt unit?
- Is it actually hot outside? RV ACs are rated to cool the interior to a certain number of degrees below ambient. At 95°F+ with direct sun on a dark roof, even a functioning AC will struggle.
- Are the ceiling vents open and unobstructed?
Likely causes requiring service: Low refrigerant (requires certified HVAC technician), failed capacitor (very common — causes the compressor to not start), failed compressor, failed fan motor.
Symptom: AC Trips the Breaker When Starting
AC compressors draw a large surge of current at startup. If your breaker trips consistently when the AC tries to start, there are two likely causes: the capacitor is failing (it provides the startup boost the compressor needs), or the shore power circuit is undersized. A hard start kit can help with the surge issue as a diagnostic step.
RV Water Pump
Symptom: Runs Continuously or Won't Shut Off
The 12V water pump should cycle on when a faucet is opened and shut off quickly after it's closed. If it runs continuously:
- There's likely a leak somewhere in the water system — check under sinks, at fittings, and around the water heater
- A faucet may not be fully closing
- The pump's internal check valve may have failed
Symptom: Weak Pressure or Won't Prime After Winterization
After dewinterizing, the pump needs to push out any remaining antifreeze and pull water from the fresh tank. Run all faucets one at a time and let the pump cycle until flow is steady. If pressure remains weak, the pump strainer screen may be clogged.
RV Slide-Out
Symptom: Slow or Won't Move
Slide-outs are either electric or hydraulic. For electric slides, check the 12V battery first — a weak battery is the most common cause of slow or stuck slides. For hydraulic systems, check the hydraulic fluid level.
If a slide is binding or moving unevenly, stop immediately. Forcing a slide against resistance can damage the slide mechanism, the slide seals, and the coach structure. This is a call-a-professional situation.
Important: Never attempt to manually override a slide without knowing your specific system. The procedure varies by manufacturer and doing it incorrectly can cause permanent damage.
Generator
Symptom: Won't Start
- Check the fuel level — most RV generators won't run when the main fuel tank drops below 1/4
- Check the oil level — low oil shutoff will prevent starting
- Check the choke position
- Has it been sitting? Fuel can go stale in 30–60 days. Use ethanol-free fuel when possible and add fuel stabilizer for storage.
Symptom: Starts But Cuts Out Under Load
If the generator starts but shuts down when you try to run the AC or other high-draw appliances, the most likely causes are: the generator is undersized for the load, the carburetor needs cleaning, or the load controller is failing.
When to Call Pals By Design
We handle all of the above — diagnostics, parts, and repair — as a mobile service throughout SE Wisconsin. You don't have to haul your rig to a shop or wait weeks for a service appointment. We come to your driveway, storage lot, or campsite.
Common calls we get:
- Fridge not cooling before a trip this weekend
- Furnace not lighting for the first cold night of fall
- AC not cooling during a Door County trip in July
- Water heater bypass left in winterization position (more common than you'd think)
- Slide won't retract before driving
Call us at (262) 302-5844 or book a service call online. We'll give you an honest assessment of whether it's a DIY fix or something that needs us on-site.
Related reading: The Only RV Maintenance Schedule You'll Ever Need | What Actually Happens When You Call a Mobile RV Tech | Your RV Roof Is Lying to You