Why your factory CO alarm is the wrong size for your RV — by a 13-year full-timer.

A Yuma RV service shop put a Bacharach Fyrite on my galley and the meter read thirty-eight. The factory alarm on my dinette cabinet had been sitting green for three days while my wife thought she had Alzheimer’s. This is what the kid behind the counter said, what I learned about UL 2034 after I drove the rig home, and what every snowbird and full-timer needs to know about the volume math nobody at Camping World mentions.

A Yuma RV service shop put a meter on my galley and the number was thirty-eight. My factory alarm sat green.

Susan had a headache going on three days. Not the kind you reach for Advil for. The kind where she’d just be quieter at supper. I asked her twice if she was coming down with something. She said no, she just felt — and I’m quoting her — foggy. That word stuck with me.

I’m seventy. Navy Chief, retired. Susan and I sold the Colonial in ’22 — the rig is the home now. 2019 Tiffin Phaeton, 33-foot diesel pusher. Q and Yuma most of the winter, Sarasota for a stretch, then we roll wherever the weather’s right. The rig isn’t part of what we own. It’s what we own.

The galley stove makes a click-click-click before it lights. Forty-seven years I’ve heard that sound. Susan’d be making coffee and I’d be at the dinette and I’d hear three clicks and then whoof, the blue ring would come up. Now every time I hear it I’m counting the seconds till the flame catches. I know what it means if it doesn’t.

First thing I did when Susan started complaining was check the regulator. Two-stage, both pigtails, soap solution on every threaded fitting I could reach. Nothing bubbled. I came back inside and told her, it’s not propane. I checked. I was wrong. It wasn’t raw propane. It was something I couldn’t smell.

She said that to me a week later. Three days of that foggy feeling and she’d been sitting at the dinette thinking she needed to call her sister and tell her. That’s what she thought it was.

Day three. I drove the rig in.

I’d run out of mechanical things to check. Propane system was tight. The Onan was vented underneath the way it’s supposed to be, the slide seal looked clean, the slide was in, and we hadn’t cracked any windows on the downwind side overnight — which is the full answer, not just the vent. I drove the coach over to a Yuma RV service shop and told the kid behind the counter, humor an old man, put a meter on it.

He pulled out a Bacharach Fyrite — yellow box, hose, probe. Kid was nineteen. Turned out later he was the owner’s grandson. He stuck the probe up next to the furnace return-air vent in the galley and his meter started climbing. Twelve. Eighteen. Twenty-six. Didn’t stop till it hit thirty-eight. He looked at me and said one sentence I’ve been telling people ever since.

“Sir, your factory alarm wasn’t going to chirp on that.”

Two hours later he had the furnace pulled. Hairline crack in the combustion chamber. You couldn’t see it without a borescope. The flue was backdrafting under certain wind conditions and pulling combustion gas into the return air. The wall between the burned air and the air we were breathing had a split in it the width of a hair. That was the whole failure mode.

The factory Safe-T-Alert sat there blinking green like everything was fine. I’d been telling myself I had it covered. I drove home to Susan and said, honey, I missed one.

The math nobody at the campfire tells you.

Here’s the part I want every snowbird and full-timer reading this to sit with.

The Colonial we sold was 2,400 square feet on two floors. The Phaeton is 240 livable. That’s one tenth. Anything that gets loose in here gets loose much faster than it would have at the old house. It’s not a feeling, it’s just math.

The factory CO detector that came with the rig is coded to the same UL 2034 alarm curve as the one screwed to my daughter’s kitchen ceiling. Same chip. Same threshold. Same time-to-alarm window. The picture on the box is a fifth-wheel. The chip inside is the same chip.

UL 2034 is the federal standard for residential CO alarms. Most full-timers have never read it. The standard says a detector is not allowed to alarm below 30 PPM — even for thirty straight days. At 70 PPM, it’s permitted to wait between 60 and 240 minutes.

Read those numbers in a stick-built kitchen and they sound reasonable. Read them in 240 square feet of moving home with the furnace cycling on every twelve minutes and they read different. The Fyrite hit 38 in the galley. Factory alarm wasn’t going to chirp on that. Not at 38. Not at 50. Not for at least an hour after we crossed 70. The math doesn’t care that I’m careful.

One more piece of the math nobody mentions. Propane is heavier than air — it gravity-settles low, pools at the deck level, fills boot-high before it climbs. Carbon monoxide is roughly the same density as air and mixes uniformly through the whole coach. That’s why a plug-in unit in a 120V outlet at sixteen-to-eighteen inches off the deck sits in the right detection zone for both: low enough to catch propane drift settling from the galley range, central enough to catch CO mixing through the breathing air. You put one near the sleeping area, one near the propane-using appliances. That’s why the 3-pack — bedroom, galley, outside compartment near the furnace.

It’s not just me saying it.

Once I had the borescope photo in my hand I went looking. I’ve been reading iRV2 and the MyRVWorks blog for years. I just hadn’t been reading them with this question in mind. Three voices come up over and over.

Koepp’s been writing this for fifteen years. Galatsis put numbers on it. Buddingh runs the company that makes the factory unit on your dinette cabinet — and he’s the one telling Truck Camper Magazine the factory unit is dangerously out of date. Read that one again. The man whose company manufactures the white plastic combo unit on your dinette cabinet is telling you it’s dangerously out of date. Not replace it every five years. Dangerously out of date. That’s him talking.

You hear about that couple up in Oregon. Valentine’s Day, ice storm, their gravity vent iced over. Walk-in clinic with headaches and confusion, sent home, back in the motorhome and didn’t come out. Their kids found them. You hear that on a Tuesday at the KOA and you think about it every Tuesday after. Mine wasn’t Oregon. Mine was Q. Mine had Susan at the dinette thinking she was forgetting her thyroid pill.

What I went looking for, and what I found.

What I wanted was a detector that knew it was in a motorhome — not a thing that came off the same assembly line as the one on my daughter’s kitchen ceiling and got slapped in the RV section at Camping World. Something that watches for the climb, not the catastrophe. Something with a screen that shows me the actual number all the time, the way the kid’s Bacharach did.

I bought a portable Forensics CO-1B for the nightstand back in February. Reads from 1 PPM. First month I had it, every time the furnace cycled I sat up to look at the number. The portable solved the not-knowing during the day. It didn’t solve the not-knowing-while-sleeping.

What solved that was a plug-in unit a snowbird friend in Sarasota mentioned in October. Brand called Alveo. Four-in-one, plug-in, no Wi-Fi, no app, no batteries. Goes in a 120V outlet. The system inside is called ForeWatch™. A live PPM number on a screen the size of a credit card.

The way Alveo describes it: a standard detector is a smoke alarm — one signal at one threshold, silence the rest of the time. ForeWatch™ is a fuel gauge — a live number on a screen, the drift visible from well below the alarm point, so you act on a trend instead of a siren. In 240 square feet where anything loose gets loose ten times faster than it would in a Colonial, the trend window is the only window that matters. Visibility starts at 30+ PPM. The factory alarm is allowed to wait for 70 over an hour. The Yuma shop’s Bacharach read 38 in my galley. The screen would have shown me 38 the second it climbed past 30. That’s the gap. That’s what I went shopping for. Here’s what I found on the unit itself.

What’s on the unit itself.

The Alveo lives on the outlet next to the bed. Plug-in. No batteries. No Wi-Fi. No app. The screen is on, all the time. Four live numbers on one screen — temperature in °F, CO in PPM, combustible gas as %LEL, and humidity %RH. All four visible at the same time. I can read it from across the coach without my glasses. Carbon monoxide, natural gas, and propane — three gases, four signals, one screen.

What it costs against what it could cost you.

I’m a numbers guy. Here’s the column.

Every Alveo detector ships with a 100-day risk-free trial and a 3-year warranty. If it doesn’t earn its spot in your home, send it back — return shipping covered. 0.7% refund rate. Less than 1 in 100 customers ask for a refund. That’s the number that told me what I needed to know. Snowbirds and full-timers don’t keep things that don’t work. We don’t have the storage.

I had it covered. I missed one. I closed the loop.

I’m not going to put Susan through that. Not the three days. Not the look she had at the dinette when she thought it was her brain.

We’re back in the desert this season. The Onan runs at 3 a.m. and I don’t sit up anymore. I hear the burner click three times. I count to one. The blue ring catches. The screen on the outlet next to the bed reads zero. That’s all I need.

If you sleep in a rig like ours — full-time, snowbird, weekends — the alarm on your dinette cabinet was not built for the volume you’re sleeping in. That’s not an opinion. That’s the math the kid with the Bacharach Fyrite was reading off his meter at the shop in Yuma. Same UL 2034 alarm curve as the one screwed to your daughter’s kitchen ceiling. Same chip. Same threshold.

You can carry the portable. You can crack the window. You can replace the factory unit with the same factory unit every five years and hope. Or you can plug in a screen that shows you the actual number and stop hoping. That’s what I did. I installed the new detector myself. The rig is the home now. I trust it the way I used to trust the Colonial.

— Charles K, retired Navy Chief
Full-time RVer, 2019 Tiffin Phaeton 33-ft · Q · Sarasota · May 2026