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Dometic RV AC Not Cooling? 5 Common Fixes for Air Conditioner Troubleshooting Guide
Ac Refrigeration Medium 2-3 hours 128 👍

Dometic RV AC Not Cooling? 5 Common Fixes for Air Conditioner Troubleshooting Guide

Walked out to my RV this morning trying to decide between calling a repair tech or troubleshooting my Dometic Brisk Air rooftop AC myself since it's showing weird operational issues. The compressor engages and fan motor operates normally, but the unit fails to produce cold air output. Temperature differential across the evaporator coil is minimal.

Unit functioned properly through previous cooling season with no apparent issues. Current symptoms include normal airflow volume but inadequate cooling capacity. What systematic diagnostic procedure should I follow to identify the root cause? Looking for a methodical troubleshooting sequence that addresses the most probable failure points in order of likelihood. …more
How to Reduce RV Interior Noise: Complete Sound Dampening Guide for Motorhomes
General Medium 4-8 hours 116 👍

How to Reduce RV Interior Noise: Complete Sound Dampening Guide for Motorhomes

Despite having a 2021 Coachmen Mirada, looking at my sound meter right now and there's 69 decibels of highway noise blasting through the cabin. My target is to achieve approximately 65 decibels for better communication with passengers.

I need a systematic approach to interior noise reduction. What are the most effective sound dampening materials and techniques for motorhomes? Specifically, I'm looking for solutions that address engine noise transmission, road noise, and any rattling components that contribute to the overall sound level.

What realistic noise reduction can I expect from proper sound deadening implementation, and what are the key areas to focus on for maximum impact? …more
Ford F53 Chassis Firewall Wiring: Finding Brake LED Through-Holes
Engine Medium 2-3 hours 106 👍

Ford F53 Chassis Firewall Wiring: Finding Brake LED Through-Holes

Opened up my 2022 Holiday Rambler 36DB for spring prep and once again I'm staring at my 2021 Ford F53 chassis firewall wondering where those brake LED through-holes are hiding. I need to run the brake indicator LED wire from my toad to the dashboard inside the motorhome, but I'm having trouble locating the best firewall penetration point.

Rather than drilling a new hole through the firewall (which I'd prefer to avoid for obvious reasons), I'm hoping to find an existing through-hole or grommet that I can utilize. I've heard that Ford F53 chassis typically have several factory access points, but I'm not sure exactly where to look or which ones would be most suitable for this type of low-voltage wiring installation.

Can anyone provide specific guidance on where to find existing firewall through-holes on the F53 chassis that would work well for routing brake indicator wiring? I want to make sure I'm using an appropriate location that won't interfere with existing systems and will provide a clean, professional installation. …more
How to Add Coleman Mach Heat Strips to RV AC Unit - Heat-Ready Control Box Installation Guide
Ac Refrigeration Hard 2-4 hours 101 👍

How to Add Coleman Mach Heat Strips to RV AC Unit - Heat-Ready Control Box Installation Guide

Tried running my RV's electric heating this winter but it's eating through power way faster than it should, so I'm looking at adding Coleman Mach heat strips. I have a SportTrek Touring 272VRK with two AC units (Coleman-Mach 13.5k BTU and 15k BTU, models 48203-069 and 48204-069) with Cool-Only Control Boxes (model 8330-752) and I'm considering adding Coleman Mach electric heat strips, but I'm worried about a few things.

First, I'm concerned about whether my current AC units are compatible with heat strips - specifically the Coleman Mach 37203-4551 Electric Heat Kit/Strip. I want to confirm this will work with my existing 8330-752 control boxes. Second, I'm worried about the electrical load - I keep reading about heat strips drawing a lot of power and I'm scared of overloading my system or tripping breakers.

Most importantly, I absolutely do NOT want to lose the ability to use my existing Suburban SF-30FQ 30,000 BTU propane furnace - it's my primary heat source and I need that independence. I currently have 9420a381 digital thermostats controlling these systems, and I want to ensure I can maintain my current setup.

Is there a way to safely add Coleman Mach heat strips using some kind of Heat-Ready Control Box without compromising my furnace operation? I just want some reassurance that this can be done properly without creating problems. …more
RV Dash AC Blower Motor Not Working? Check These Hidden Fuses First
Electrical Medium 2-4 hours 100 👍

RV Dash AC Blower Motor Not Working? Check These Hidden Fuses First

Last week I'm trying to decide between shelling out hundreds for an RV tech or tackling this myself after my F53 chassis motorhome's dash A/C blower motor completely died. I've checked all the obvious fuses in the main fuse panels, but nothing seems blown.

I discovered something crucial that might help others: Fleetwood added a hidden 25 amp fuse wire-tied above the emergency brake, not shown in standard Ford chassis diagrams. In my case, this was the culprit. As a temporary fix, I even ran a wire directly from my lighter plug with a switch to get some air movement.

I'm wondering if other RV owners might have similar hidden electrical components that aren't in standard chassis wiring documentation? Before taking it to a shop, I recommend carefully checking behind panels and tracing wires, especially looking near the dashboard area above the emergency brake for manufacturer-specific fuses. …more
Onan 5500 Generator Shuts Down Under Load: Troubleshooting Guide
Engine Medium 2-3 hours 97 👍

Onan 5500 Generator Shuts Down Under Load: Troubleshooting Guide

Onan 5500 runs perfectly at idle but kills itself within 30 seconds of turning on the AC. Been fine for years and suddenly can't handle any real load. Fuel filter is new, oil is fresh, and it starts right up every time — just dies the moment I ask it to actually work. …more

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Ford F53 460 Engine Timing Marks: How to Locate and Check (Step-by-Step Guide)
Engine Medium 30 minutes 85 👍

Ford F53 460 Engine Timing Marks: How to Locate and Check (Step-by-Step Guide)

About to drop serious cash on a used Class A motorhome with a Ford F53 460 engine — should I check those timing marks myself or am I asking for trouble? Where exactly are the timing marks located? I can see the harmonic balancer but having trouble spotting the marks and pointer. What's the best way to make them visible and actually read them with a timing light? …more
Suburban SF-30 Furnace Replacement: Complete Unit vs Core Guide for RV Owners
Propane Medium 4 hours 84 👍

Suburban SF-30 Furnace Replacement: Complete Unit vs Core Guide for RV Owners

Somewhere between our freezing mountain trip last month and now, my 2002 Born Free's SF-30 furnace died completely and I'm torn between replacing the core versus the whole unit. I believe it's a Suburban SF-30 model. I've been doing some research and see there are two options - I can buy a complete furnace replacement or just get a replacement core that supposedly slides into the existing SF-30 housing for about half the price.

I'm honestly not sure which route to go. The cost savings on the core is tempting, but I don't want to make the wrong choice and end up with more problems. As someone who's still learning about RV maintenance, would you recommend getting the complete unit or would the core replacement work just as well? Any guidance would be really appreciated! …more
RV AC Won't Start After Capacitor Replacement? 5 Easy Fixes
Electrical Medium 1-2 hours 83 👍

RV AC Won't Start After Capacitor Replacement? 5 Easy Fixes

Standing here looking at my RV AC unit right now and I can see the brand new capacitor I just installed, but the entire system is stone cold dead. I have a 2012 King Aire 4584 and recently tried replacing the run capacitor on my rear A/C unit because it was only running for about two minutes at a time and the compressor was getting really hot.

Now I'm in a worse situation - the unit won't start at all, even after I put the old capacitor back in. I'm wondering if there are some basic things I should be checking that I might have missed? Could I have blown a fuse or tripped something during the replacement? The compressor was pretty hot when I was working on it.

I'm hoping there might be some kind of reset button or other troubleshooting steps I should try before calling a repair tech. Any advice would be really appreciated! …more
Advent RV Air Conditioner Not Cooling? Complete KoolRV Adapter Fix Guide
Ac Refrigeration Medium 2-4 hours 81 👍

Advent RV Air Conditioner Not Cooling? Complete KoolRV Adapter Fix Guide

Around 6 AM I walked out to my fifth wheel and spotted my Advent air conditioner running but barely pushing any cool air through the vents. I replaced my old Coleman AC with an Advent, mainly due to price, but I'm not getting good cooling during the heat of the day. I've found that opening the slide vents on the ceiling cover helps a bit.

I'm considering using a KoolRV adapter like I had with my previous Coleman, but no adapter currently exists for the Advent. I've noticed the cold air discharge opening is located in the corner instead of the center, which I think is causing air turbulence and restricting duct airflow.

My main concern is whether restricting the airflow too much could cause problems like freezing up or other damage to the AC system. I've also seen that installing these adapters involves removing some kind of dividing wall inside the unit, but I don't understand why that's necessary.

Could someone explain if there are risks to restricting airflow and why that dividing wall needs to be removed? I want to make sure I understand what I'm getting into before I try any modifications. Right now, it's starting to cool down here in the Everglades, but I still want to improve my cooling performance. Thanks for any guidance! …more
Newmar Bay Star 3826 Black Tank Vent Pipe Routing: Complete RV Location Guide
Plumbing Medium 45 minutes 79 👍

Newmar Bay Star 3826 Black Tank Vent Pipe Routing: Complete RV Location Guide

This dangerous sewer smell is seeping into my Newmar Bay Star 3826 where my kids are sleeping—could the black tank vent pipe routing be putting my family at risk? I can trace the half bath black tank vent line running through or adjacent to the electrical cabinet area, but I require confirmation of this routing.

The rear bathroom black tank vent pathway is less apparent during my inspection. I need to identify where this vent line routes from the tank connection point up to the roof termination. Understanding both vent pipe locations is critical for proper system maintenance and troubleshooting potential blockage issues. …more
Coleman 9420-381 RV Thermostat Voltage Drop: Complete Repair Guide & Solutions
Propane Medium 45 minutes 78 👍

Coleman 9420-381 RV Thermostat Voltage Drop: Complete Repair Guide & Solutions

Pulled the same wire swap trick that fixed my old analog RV thermostat's voltage drop, but this new Coleman 9420-381 digital replacement is behaving completely different. Everything worked great all summer with the AC, but now that heating season is here, I'm having major problems.

The furnace keeps short-cycling terribly - the burner fires for maybe 3-20 seconds, shuts off, then the whole cycle repeats. I've already ruled out the furnace itself (replaced the board, checked sail switch and limit switch). Through testing, I discovered the furnace is steady at 13.4V, but when the thermostat calls for heat, the voltage it sends back slowly drops from 13V down to around 10V, then the burner shuts down.

If I short the two furnace wires directly, the furnace runs perfectly. I suspect the thermostat's solid state components are failing. I'm wondering:
1 Has anyone else seen this issue?
2 Are others using this 9420-381 thermostat without problems?

I really like the digital features, but need a reliable solution. …more
RV AC Humming But No Air Flow? Fix It Yourself (2024 Guide)
Ac Refrigeration Medium 2-3 hours 78 👍

RV AC Humming But No Air Flow? Fix It Yourself (2024 Guide)

I tried everything I could think of, but probably a dumb question—why would my 2006 Sightseer 30B's AC hum after storage but blow zero air? big mistake lol. The thing is humming like crazy but zero air coming out of any vents. It's loud enough to wake the neighbors but doing absolutely nothing.

I'm guessing something got stuck or seized up while it was sitting? Anyone know what typically causes this after long storage periods? Really hoping it's something I can fix myself before calling a repair guy. …more

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How to Locate Your RV's Engine Coolant Outlet and Heater Core Connections
Engine Easy 15 min to identify 76 👍

How to Locate Your RV's Engine Coolant Outlet and Heater Core Connections

Standing in my driveway at 2 AM with my overheating 2003 F53 6.8 V10 Rexhall Vision — desperately need to locate the engine coolant outlet and heater core connections before dawn departure. I can see the heater hoses going through the firewall, but I'm not sure where exactly on the engine the hot coolant comes out to supply the heater core.

I know there should be a supply line that sends hot coolant to the heater core and a return line that brings it back, but I'm having trouble identifying which is which and where they connect on the engine. Could someone help me understand where to look for the coolant outlet that feeds the heater core? I'd really appreciate any guidance on tracing these connections! …more
RV AC Not Cooling Properly? Complete Troubleshooting & Repair Guide
Ac Refrigeration Medium 2-3 hours 74 👍

RV AC Not Cooling Properly? Complete Troubleshooting & Repair Guide

Standing here after replacing my RV's AC compressor yesterday but it's still barely blowing cold air — did I mess something up? My dual AC setup absolutely crushes it when it's blazing hot outside - we're talking 95+ degree days and it'll knock the temp down a solid 15 degrees no problem. But now that the weather's cooled off to like 70-75 degrees, the darn things can't even keep up with the outdoor temperature. Set the thermostat to 69, outside temp is 69, and I'm still sitting at 75+ inside the rig.

I actually tested it yesterday - turned off the AC completely, opened windows and ran exhaust fans, and got better cooling than with the AC running! Now I'm doing this weird combo of AC plus open windows just to stay comfortable. What gives? Why would my AC units lose their mojo when the weather gets easier on them? Is this some kind of airflow issue or what? …more
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