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RV AC Freezing Up? Fix Ice on Coils in 5 Steps
Ac Refrigeration Easy 30 minutes 131 👍

RV AC Freezing Up? Fix Ice on Coils in 5 Steps

Turned on my RV's AC as a total newbie and watched it run perfectly for an hour before becoming a frozen disaster that won't cool. I can literally see ice building up on the coils, and then it's game over until everything thaws out.

This has happened a few times now and I'm getting tired of sitting in a hot RV waiting for the thing to defrost. What actually causes AC units to freeze up like this? And more importantly, how do I stop it from happening again? I'm guessing it's something simple I'm missing, but I'd rather fix it right than keep dealing with this cycle. …more
Coleman Mach AC Fuse Blows With Battery On - Rockwood Fix
Ac Refrigeration Medium 2-3 hours for diagnosis, professional repair likely needed 122 👍

Coleman Mach AC Fuse Blows With Battery On - Rockwood Fix

Found out the hard way that the previous owner of my 2019 Rockwood Minilite 2509s left me with a Coleman Mach AC that blows fuses instantly when I flip on the battery. The AC fuse blows instantly when I turn on the battery disconnect, before the AC is even activated. The fuse literally blows before it's completely seated in the panel.

This began two weeks ago without warning - the system had been functioning normally prior to this. Initial fuse replacement provided temporary operation, but the problem returned on the next trip with the fuse already blown upon arrival.

Given the immediate fuse failure with just battery power connected, what type of electrical fault would cause this symptom pattern in a Coleman Mach unit, and what's the most likely location of the problem in the AC circuit? …more
Ford F53 V10 RV Chassis Repair Shops Near Raleigh NC - Engine Service
Engine Easy N/A - finding shop 110 👍

Ford F53 V10 RV Chassis Repair Shops Near Raleigh NC - Engine Service

My Ford F53 V10 is showing misfire codes P0301 and P0303, but my compression test reads 180 PSI when everything says it should be around 150 PSI. I'm located near Raleigh, North Carolina, and I need to get some mechanical work done - specifically repairs to the exhaust manifold bolts and air conditioning system work.

The problem I'm running into is that when I call Ford dealerships in the area, they keep telling me they don't work on motorhomes, even though it's a Ford chassis. This seems crazy to me since the engine and drivetrain components should be the same as other Ford vehicles. The exhaust manifold issue and AC problems are fairly standard automotive repairs, so I don't understand why the Ford connection isn't helping me here.

What type of repair facilities should I be looking for instead? Are there specific shops or service centers near Raleigh that specialize in F53 chassis work, or should I be approaching this differently? I just need somewhere that can competently handle these mechanical repairs on my motorhome without the runaround. …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 AC Won't Start After Capacitor Replacement? 5 Easy Fixes
Electrical Medium 1-2 hours 84 👍

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
Coleman RV AC Remote Sensor Wrong Resistance: Troubleshooting Guide
Ac Refrigeration Medium 1-2 hours 81 👍

Coleman RV AC Remote Sensor Wrong Resistance: Troubleshooting Guide

Our 2013 Phaeton's Coleman AC remote sensor is throwing wrong resistance readings and I've got my multimeter ready to fix this myself — just need the correct values to check against. The remote temp sensor in my living area started reading 99°F constantly, so I checked the resistance and found it was only 9kohms while the working sensor reads 90kohms at 82°F.

I ordered the replacement part 8330-3101 (which supposedly replaces my old 8330-309), but I'm worried because the new sensor ALSO measures 9kohms right out of the package - exactly like my "bad" one. I've tested both thermostats and they work fine when I swap the sensor leads.

I'm hesitant to install this new sensor since the resistance seems wrong. Could I damage my thermostat or AC system if there's a compatibility issue? Should I be measuring resistance differently, or is there a wiring problem I'm missing? I don't want to make things worse by installing the wrong part. …more

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Coleman 9420-381 RV Thermostat Voltage Drop: Complete Repair Guide & Solutions
Propane Medium 45 minutes 80 👍

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 Unit Failed After 3 Years - Warranty Claims & Repair Guide
Ac Refrigeration Easy Warranty process 79 👍

RV AC Unit Failed After 3 Years - Warranty Claims & Repair Guide

Got a dead front AC unit on my buddy's 2022 Holiday Rambler Endeavor at 2 AM — need this figured out before we hit the road tomorrow morning. We're talking a rig that's not even 3 years old yet! He's got two other roof units still working fine, but this one just gave up.

Is this typical for RV air conditioners? Seems crazy short for something that expensive. Should he be looking at warranty coverage or is he stuck buying a new unit? Any advice on how to handle this with the manufacturer or dealer would be awesome! …more
RV AC Humming But No Air Flow? Fix It Yourself (2024 Guide)
Ac Refrigeration Medium 2-3 hours 79 👍

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
Fix Coleman-Mach Multi-Zone AC Control Box Problems
Ac Refrigeration Medium 2 hours 76 👍

Fix Coleman-Mach Multi-Zone AC Control Box Problems

My 2003 Fleetwood Excursion came with a nasty surprise — the previous owner left the Coleman-Mach multi-zone AC control box completely destroyed. I replaced my old control box with a model 9430A751, but now I'm having serious issues with my original Coleman Mach ZC thermostat.

The new control box has SIG 1 and SIG 2 terminals, but my original only had a single SIG terminal. I've confirmed the heat pump and zone jumpers are set to zone 1 and no heat pump. My thermostat lights up on Zone 1 briefly, then switches to Zone 2 and becomes completely unresponsive. I'm only running a single-zone setup with one purple signal wire.

When I plug in the control box, I get three green LED 1 flashes. I'm getting increasingly concerned that this 9430A751 control box isn't compatible with my system at all. Should I stop trying to make this work before I cause more problems? Is there a fundamental difference between control boxes with dual SIG terminals versus single SIG terminals that I'm missing? …more
Coleman Mach 10 AC Motor Replacement - Shaft Too Long Fix
Ac Refrigeration Medium 2-4 hours 76 👍

Coleman Mach 10 AC Motor Replacement - Shaft Too Long Fix

Apparently this Coleman Mach 10 AC motor replacement is eating through my entire weekend because the new shaft is way too long for my Winnebago Era. The new motor shaft is way too long compared to what I'm seeing in YouTube videos of other Coleman units. The old blower wheel is stuck tight on the original shaft too - thing won't budge!

Anyone dealt with this before? Do I need to trim the shaft somehow, or is there a better way to handle the length issue? And what's the trick for getting that stubborn blower wheel off without wrecking everything? …more
RV Heat Pump Amp Draw: How Many Amps Does Your Unit Use?
Ac Refrigeration Easy 30 minutes 75 👍

RV Heat Pump Amp Draw: How Many Amps Does Your Unit Use?

Turned down a Class A with a heat pump because I'm terrified of being that neighbor constantly tripping breakers — am I overthinking this? We're plugged into 30-amp service at home while I pretend to know what I'm doing with all these fancy RV features.

Basically, I need to know how many amps this heat pump is going to suck down when it kicks on. I'm already running the usual suspects - fridge, lights, maybe the TV so I can ignore my responsibilities - and I'd rather not find out the hard way that I'm overloading everything. Anyone know the typical amp draw so I can at least look semi-competent when explaining to my spouse why the power keeps cutting out? …more
Pace Arrow Zone AC Not Working - How to Fix Blinking Green LED Error Code
Ac Refrigeration Medium 1-2 hours 74 👍

Pace Arrow Zone AC Not Working - How to Fix Blinking Green LED Error Code

Noticed my 06 Pace Arrow is 18 years old and the dual zone AC's zone 1 is starting to completely fail with a blinking green LED — repair or replace? Zone 2 is working fine with a steady green LED on the control board, but zone 1 has this annoying blinking green LED that I'm pretty sure means something's wrong.

The thermostat isn't showing zone 1 anymore either. I'm thinking it's gotta be the control board since zone 2 is chugging along just fine with the same setup. Anyone know if a blinking LED definitely means the board is toast? And is there a way to test this without just buying a new board and hoping for the best? …more

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Micro-Air 355 Thermostat Wiring Issues: Multi-Zone RV HVAC Troubleshooting Guide
Electrical Hard 2-4 hours 70 👍

Micro-Air 355 Thermostat Wiring Issues: Multi-Zone RV HVAC Troubleshooting Guide

Around the third day into our trip, my Micro-Air 355 thermostat has zones not responding, temperature readings jumping randomly, AND the whole system cycling on and off every few minutes all at once. I replaced my old RV Comfort.ZC thermostat with a Micro-Air 355 and nothing is working right. The old thermostat controlled both zones perfectly, but now I've got a complete mess.

My current wire connections include:
- Red 12v in *
- White 12v out *
- White B-
- Green SIG 1 *
- Brown SIG 2 *
- Red R+
- Blue B-
- Yellow R+ (not used on old thermostat)

Zone 1 cool doesn't work AT ALL, but the furnace works fine. Zone 2 is backwards - cool works but furnace won't kick on. Even worse, once I switch from zone 1 to zone 2, I can't get back to zone 1! I have to reset the whole thing.

I've got these extra yellow and orange wires that were showing voltage when zone 2 furnace should be running. My Coleman Mach units are fine - this has to be a wiring difference between the thermostats. I really thought this would be plug-and-play! Is there something specific about how the Micro-Air 355 handles SIG1 and SIG2 wires differently than the RV Comfort.ZC? I'm starting to think I need professional help with this multi-zone setup. …more
How to ID Roof AC Model on 2004 Fleetwood Expedition
Ac Refrigeration Easy 30 minutes 47 👍

How to ID Roof AC Model on 2004 Fleetwood Expedition

This drives me crazy — my 2004 Fleetwood Expedition's roof AC only acts up when it's above 85 degrees outside, but I can't identify the model number to order replacement parts. I've got a 2004 Fleetwood Expedition and the front roof air conditioner isn't working properly. I went up on the roof to check it out, but the sticker with all the model information is completely weathered and unreadable. I can make out that it might be a Dometic or Coleman unit, but I'm not sure. Without the model number, I'm having trouble finding parts or even knowing what I'm dealing with. Is there another way to figure out what AC unit I have? Any guidance would be really appreciated - I'm still learning about all this RV stuff! …more
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