RV Gas Detector Beeps Every Minute at Night - How to Fix

What's Going On

Your gas detector beeping consistently from 7PM to 7AM on a once-per-minute cycle is most likely indicating a low voltage condition rather than a gas leak. Since this pattern coincides with evening hours when your RV's electrical demand is highest (lights, TV, refrigerator cycling), and you're shore-powered with 4 batteries, this points to either a failing gas detector unit that's become voltage-sensitive, or a power supply issue to the detector itself. The fact that it stops at 7AM when electrical loads typically decrease supports this diagnosis rather than an actual gas detection problem.

Before you spend money on a replacement detector, there's a high probability this is either a simple calibration issue, a dirty sensor that needs cleaning, or the detector has reached its end-of-life and is giving false alarms. Most RV gas detectors have manufacturer-specified lifespans (typically 5-7 years, but check your model's specifications) and will start giving erratic readings as they age, especially during high electrical demand periods.

Why This Happens

Gas detectors in RVs are extremely sensitive to voltage fluctuations, and yours is showing classic symptoms of voltage sensitivity during peak electrical usage hours. When you're running lights, charging devices, and other 12V accessories in the evening, even though you're on shore power, there can be voltage drops at the detector if your converter isn't maintaining steady 12V output or if there's resistance in the wiring connections.

Another common cause is sensor contamination from cooking vapors, cleaning products, or even high humidity, which can cause false readings. The timing pattern you're describing - 7PM to 7AM - strongly suggests the detector is reacting to electrical conditions rather than actual gas presence. Additionally, if your detector is more than 5 years old, the sensor may be degrading and becoming hypersensitive to normal propane traces that are always present in small amounts.

Temperature changes during evening hours can also affect older detectors, as can the natural settling of propane (which is heavier than air) during cooler nighttime temperatures, even if there's no actual leak.

Getting Ready

Start by locating your gas detector - it's typically mounted low on a wall since propane settles downward. You'll need a multimeter to check voltage at the detector, some compressed air or a soft brush for cleaning, and possibly a small screwdriver to remove the detector from its mounting bracket. Make sure all propane appliances are turned off and consider doing this work during daylight hours for safety.

Check your RV's manual or the detector itself for the model number and manufacturing date. Most detectors have a sticker indicating when they were made. If it's over 5 years old, replacement is likely your best long-term solution, but you can still try the troubleshooting steps first.

Have your multimeter ready to check the voltage at the detector during both the problematic evening hours and during the day when it's quiet. You'll also want to inspect all propane connections, even though this likely isn't a real gas leak, just to be thorough.

Walking Through the Fix

First, check the voltage at your gas detector during the evening when it's beeping. Remove the detector from its bracket (usually just pulls out) and check the voltage on the wires with your multimeter while power is on. Exercise extreme caution when working with live wires - ensure multimeter leads are properly connected before touching wires and keep hands away from bare conductors. You should see a steady 12V. If you're seeing voltage drops below 11.5V during the beeping periods, you've found your problem - either your converter isn't keeping up with demand, or there's a wiring issue.

With power disconnected to the detector, clean the detector sensor with very light compressed air pressure (if recommended by manufacturer), blowing out any dust or debris from the sensor chamber. Use caution as high pressure air can damage sensitive sensor components. Avoid using any cleaning chemicals near the detector. If accessible, gently brush the sensor area with a soft brush. Many false alarms are caused by accumulated cooking grease, dust, or other contaminants on the sensor.

Next, check all connections to the detector for corrosion or looseness. Clean any corroded terminals with fine sandpaper and ensure tight connections. Test the detector by pressing its test button - it should beep loudly, confirming the unit itself is functional.

If cleaning doesn't solve it and voltage is steady, try temporarily relocating the detector to a different 12V source (like directly to your battery) during the problem hours. WARNING: This temporarily leaves your RV without gas detection protection. Only perform this test if you can ensure all propane appliances are turned off at their valves, the main propane tank valve is closed, and no one uses any propane during the entire test period. If the beeping stops, you've confirmed it's a power supply issue to that circuit. If it continues beeping even with clean power, the detector itself is failing and needs replacement.

Beyond DIY Territory

If your troubleshooting shows steady voltage and cleaning doesn't resolve the issue, and especially if your detector is over 5 years old, replacement is your safest bet. A new RV gas detector typically costs $40-80 and is a straightforward swap - just match the wire connections and mount it in the same location. Don't delay this repair, as a malfunctioning gas detector is a serious safety concern.

However, if you discovered voltage issues during your testing, you'll need to address the electrical problem first. This might involve checking your converter output, inspecting the 12V distribution panel for loose connections, or having an RV technician diagnose why your electrical system can't maintain steady voltage during normal evening loads.

Call a professional immediately if you ever smell propane or if the detector alarm becomes constant rather than the once-per-minute pattern you described. While your current symptom pattern suggests electrical issues rather than gas detection, any change in the alarm pattern should be treated as a potential real gas leak until proven otherwise.