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RV LP Gas Detector False Alarms: Complete Troubleshooting Guide
Propane Easy 30 min 121 👍

RV LP Gas Detector False Alarms: Complete Troubleshooting Guide

Already tried everything but my RV's LP gas detector has false alarms in the garage, keeps beeping at random times, AND won't reset properly. Even with the LP tank completely shut off, the alarm still goes off within hours. It's located in the bottom of the fridge cabinet.

I've checked everywhere for actual leaks - can't smell anything, and all my appliances still light immediately when I take the RV out. The detector seems fine outside but becomes a nightmare indoors. I'm wondering if it's the sensor going bad, poor placement, or if there are other things that can trigger these detectors besides actual propane leaks?

I really need a complete breakdown of what causes these false alarms and how to fix this issue once and for all. Should I be looking at replacing the detector entirely, or are there troubleshooting steps I'm missing? …more
RV Furnace Blowing Cold Air? Fix Ignition Issues Fast
Propane Medium 45 minutes 98 👍

RV Furnace Blowing Cold Air? Fix Ignition Issues Fast

Staring at my RV furnace blowing cold air at 2 AM with the fan running — desperately need this fixed before morning hits.
I can hear it trying to ignite but it never actually lights. What are the most common causes when a furnace won't ignite? Need to know what components to check and how to diagnose ignition problems myself. …more
Atwood AFMD35 Furnace Playing Peek-a-Boo - How to Clean Flame Sensor & Fix Short Cycling
Propane Medium 30-60 minutes 95 👍 1

Atwood AFMD35 Furnace Playing Peek-a-Boo - How to Clean Flame Sensor & Fix Short Cycling

Staring at my Atwood AFMD35 manual that claims it should stay running once lit, but mine keeps shutting off every few minutes like it's playing peek-a-boo. It fires up beautifully for about 5-10 seconds, gets my hopes up that I won't freeze tonight, then promptly shuts off like it's having second thoughts about this whole "heating the RV" thing.

I've ruled out the sail switch and high temp limit since it actually lights (small victories in RV life, right?). I'm pretty sure the flame sensor is the culprit here, but I've never cleaned one before. How do I clean this mysterious little part, and what's the best way to access it on this model? Because apparently my furnace thinks playing hard-to-get is charming! …more
Dometic RV Furnace Runs 10 Seconds Then Shuts Off - Complete Troubleshooting Guide
Propane Medium 1-2 hours 93 👍

Dometic RV Furnace Runs 10 Seconds Then Shuts Off - Complete Troubleshooting Guide

The YouTube tutorials I followed to fix my Dometic DFMD35111 furnace that runs 10 seconds then dies actually made it worse—now it won't even start! Every time I try to run it, the same thing happens - it fires up, runs for exactly 10 seconds, then just shuts off completely. This has been going on for weeks now and I'm getting desperate since the weather is getting colder.

I've been trying to troubleshoot this myself but honestly don't know where to start. I can hear the blower running and the unit seems to ignite initially, but then it just dies. Is this a common problem with these Dometic units? I'm really hoping this is something I can fix myself rather than having to call out an expensive repair tech.

What are the most likely culprits when a furnace runs for just 10 seconds then shuts down? I need to know what components to check first before I start taking things apart. …more
Norcold N842IM 'No CO' Error Fix - Complete Propane Troubleshooting Guide
Ac Refrigeration Medium 45 minutes 92 👍

Norcold N842IM 'No CO' Error Fix - Complete Propane Troubleshooting Guide

Apparently everyone has a different theory about my Norcold N842IM's 'No CO' error—my neighbor swears the propane tank's empty, the RV dealer blames the thermocouple, and YouTube insists it's just dirty burners. The fridge works absolutely perfectly when we're plugged into shore power and running on AC - no problems whatsoever with cooling performance or any error codes.

The real problem starts when we disconnect from shore power and head out on the road. The refrigerator switches over to propane mode without any issues initially, and everything seems to be working normally for the first several hours. However, after approximately 8-9 hours of running on propane, I consistently get an alarm and a 'no CO' error code displayed. I've been turning the refrigerator off for about an hour (though I'm not sure if that's the right amount of time), and when I restart it, it runs fine for another 8-9 hour cycle before the same error occurs again.

I'm wondering what could be causing this specific 'no CO' error to appear after this consistent timeframe when running on propane. Is this related to combustion problems, ventilation issues, or something with the propane system components? I'd really appreciate some guidance on what I should be checking and how to properly troubleshoot this recurring problem. …more
Norcold N7LX.3F Running Too Often: Complete Troubleshooting & Repair Guide
Ac Refrigeration Medium 2-3 hours 88 👍

Norcold N7LX.3F Running Too Often: Complete Troubleshooting & Repair Guide

Standing in the RV supply store staring at replacement thermostats and control boards with no clue which one will actually stop my Norcold N7LX.3F from running constantly. It's been running way more frequently than it ever has before, and I can't figure out what's wrong. The cooling seems off too - items aren't staying as cold as they should be.

I've already checked the obvious stuff like making sure the vents aren't blocked and the unit is level, but something is definitely not right. The fridge just keeps cycling on and off constantly, which has me worried about both the power consumption and whether there's a bigger problem developing.

What should I be looking at to diagnose cooling efficiency issues? I really need to get this sorted before our next camping trip! …more

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Norcold N611 NO CO Error Code: Complete Repair Guide for Flashing Warning Lights
Ac Refrigeration Medium 2-4 hours 83 👍

Norcold N611 NO CO Error Code: Complete Repair Guide for Flashing Warning Lights

Staring at my 2007 Norcold N611's flashing NO CO lights shutting everything down — is there a DIY fix under $50 since I can't swing a $300 service call? The fridge loses cooling and then locks out completely. I can reset it and it works for a few days or weeks, then the same cycle repeats.

What exactly does the NO CO error code mean and what causes it? Need to understand what's happening before I start throwing more parts at this problem. …more
RV Tankless Water Heater Problems at High Altitude: Performance & Efficiency Guide
Propane Easy N/A - informational 79 👍

RV Tankless Water Heater Problems at High Altitude: Performance & Efficiency Guide

Already followed my RV tankless water heater manual's high altitude instructions, but I'm still getting terrible performance and efficiency issues at mountain campgrounds between 5,000 and 8,000 feet. My travel trailer came equipped with a tankless on-demand water heater from the factory, and I'm concerned about how it will perform at these higher altitudes.

I've heard that propane appliances can have issues with combustion efficiency when there's less oxygen available in the thin mountain air. Specifically, I'm wondering about quantifiable performance losses - like what percentage of heating capacity I might lose per thousand feet of elevation gain. I'm also concerned about potential operational problems like flame failure or the unit shutting down completely at certain altitudes.

For context, most of my regular camping is done below 2,000 feet where the water heater works fine, but these upcoming mountain trips will be well above 4,500 feet elevation. Should I be worried about the tankless system's reliability at these altitudes, or am I overthinking this? Would I be better off considering a replacement with a traditional tank-style water heater if I plan to do more high-altitude camping in the future? …more
Suburban SW6D Water Heater Won't Stay Lit: Quick DIY Troubleshooting Guide
Propane Medium 45 minutes 79 👍

Suburban SW6D Water Heater Won't Stay Lit: Quick DIY Troubleshooting Guide

This Suburban SW6D water heater pilot light keeps going out every single time I try to fire it up. The flame keeps going out after lighting, but only when the access door is closed. When I leave the door open, it stays lit just fine.

This seems like it could be dangerous - I don't want to cause a gas leak or explosion by trying random fixes. Is this likely a combustion air problem or some kind of safety switch issue? I'm hesitant to start taking things apart without knowing what I'm dealing with, but I also don't want to keep running it with the door open if that's unsafe too. …more
Suburban KT30 Furnace 521099 Circuit Board Upgrade: Complete Wiring Fixes & Spark Troubleshooting
Propane Medium 2-3 hours 77 👍

Suburban KT30 Furnace 521099 Circuit Board Upgrade: Complete Wiring Fixes & Spark Troubleshooting

The multimeter's charged and screwdrivers are laid out — ready to fix this Suburban KT30 Furnace 521099 circuit board myself, just need the proper wiring sequence. I upgraded my Suburban KT30 furnace with the new 521099 circuit board and 528039 adapter harness after the original board failed. The good news is I now have power to the gas valve through the brown wire - that part's working!

But here's what's driving me crazy: when the gas valve opens, I'm only getting ONE spark at the electrode instead of the continuous 5-7 seconds of sparking I should be getting. I've been digging through wiring diagrams and realized the old board had a dedicated wire for the flame sensor, but the new setup just has me grounding that old flame sensor wire.

I'm pretty sure this flame sensor wiring issue is what's causing the single spark problem instead of continuous ignition, but I can't figure out how to properly wire it with this new 521099 board. Has anyone successfully done this upgrade and gotten the flame sensor circuit working correctly? …more
Suburban SF-42Q Furnace Shuts Off After 5-10 Minutes: Troubleshooting
Propane Hard 1-3 hours 75 👍

Suburban SF-42Q Furnace Shuts Off After 5-10 Minutes: Troubleshooting

Pulled into camp last night and there's this sharp clicking sound followed by dead silence when my Suburban SF-42Q furnace burner dies after 5-10 minutes. The system attempts to re-ignite several times before giving up and shutting down completely. Cycling power restarts the unit, but the same pattern repeats.

I've verified the sail switch operates correctly and the thermal limit switch shows continuity when cold. The unit starts immediately and heats effectively during those initial minutes before failure. What are the most likely causes for this specific shutdown pattern, and what diagnostic steps should I prioritize to identify whether this is an overheating issue, fuel delivery problem, or control board failure? …more
How to Fix Suburban SF-42 Furnace Rumble and Backfire Issues
Propane Medium 2-3 hours 75 👍

How to Fix Suburban SF-42 Furnace Rumble and Backfire Issues

I looked everywhere online for answers but as a first-time RV owner, I'm completely lost why my 2003 Alpine coach's Suburban SF-42 furnace keeps rumbling and backfiring nonstop! This thing fires up fine initially, but then it starts making these awful rumbling sounds and actually backfires through the intake - scared the hell out of me the first time it happened. The worst part is it's not heating worth a damn even though it runs constantly.

I've already cleaned what I could reach and checked for obvious blockages, but I'm wondering if this could be an air-fuel mixture issue? The unit is over 20 years old now, so I'm prepared for the possibility that major components might need replacing. Could this be related to gas pressure problems, or maybe the igniter is going bad and causing delayed ignition? I really need to understand what's actually causing these rumbling and backfire symptoms so I know what to focus on next. …more
RV Furnace Won't Ignite But Blower Runs: Complete Troubleshooting Guide
Propane Medium 1-2 hours 75 👍

RV Furnace Won't Ignite But Blower Runs: Complete Troubleshooting Guide

Staring at my 2022 Thor Quantum SE28 furnace after following three YouTube tutorials that somehow made it worse — now it won't ignite despite the blower running perfectly. The unit is getting power and the blower motor kicks on when I call for heat, but I'm not getting any ignition at all - no flame, no heat output. I can hear the blower running strong, so it's definitely getting electrical power, but something in the ignition sequence isn't working.

I've got plenty of propane (3/4 tank) and my stove works fine, so I know gas is flowing to the RV. This is actually the first time I've tried to fire up the furnace this season after it sat unused all summer. The outside vents look clean and I don't see any obvious obstructions, but I'm wondering if there are specific components in the ignition system I should be checking.

What are the most common failure points when you have blower operation but no ignition? I'd like to work through the troubleshooting systematically rather than just throwing parts at it. Are there particular components like switches or igniters that typically cause this symptom? …more

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Used Onan 4000 Generator Buying Guide: Essential Inspection Checklist for RV Owners
Engine Medium 1 hour inspection 72 👍

Used Onan 4000 Generator Buying Guide: Essential Inspection Checklist for RV Owners

Spent an hour inspecting this Craigslist Onan 4000 from Villa Rica and it's doing something bizarre — everything looks perfect but won't even attempt to turn over. I'm seeing prices ranging from $500 to $3000+ and want to understand what's a fair price. The original link was https://atlanta.craigslist.org/wat/rvs/d/villa-rica-onan-cummins-generator/7895531063.html.

What should I be looking for when I go check one out? Don't want to buy someone else's headache but also don't want to pass on a good deal because I'm being too picky. Any red flags I should watch out for? …more
Dometic RV Furnace Flame Lights Then Dies: Complete Fix Guide 2024
Propane Medium 1-2 hours 72 👍

Dometic RV Furnace Flame Lights Then Dies: Complete Fix Guide 2024

My Dometic DFMD35111 furnace does the same infuriating thing every fall — lights perfectly on startup then immediately dies out. The flame lights up no problem, but then it just dies out randomly - sometimes after like 3 seconds, other times it'll run for several minutes before cutting out. It's totally unpredictable.

I've already cleaned out some bugs from the burner area and messed with the sail switch, but it's still doing this intermittent thing. The flame sensor looks pretty gunky though. Could that cause these random flame failures? And what else should I be checking when the burn time is all over the place like this? …more
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