When Diane and I are on the road there is one cardinal rule I follow when it comes to the RV kitchen–STAY OUT! LOL. Well, that’s not entirely true, I am allowed to do the dishes.
I’m happy to let Diane handle the cooking because she makes delicious, healthy food and presents it beautifully, artistically. BUT WAIT… THERE’S MORE… Diane’s a whiz at multi-purposing: finding multiple things that can be done with one thing or another, and this is advantageous to RVers who are always battling to minimize the weight of things and the space they consume. When it comes to the delicious homemade muffins that Diane bakes (recipe follows) she’s found some silicone baking cups that not only take up a lot less room and weigh a lot less than a traditional muffin tin but they can be used in the RV or at home for many things besides baking muffins and cupcakes. So, with no further adieu here is what Diane has to say about the OXO Baking Cups and easily baking some delicious, home made muffins in the RV…[READ MORE]
There is an insidious hidden problem with the installations of many RV furnaces putting them on a collision course with a premature death. Yours could be one of them. Mine was.
I discovered a problem with my RV furnace, a problem I know for a fact that other people have had, and one that may go undiscovered until it’s too late. Actually, the problem has to do with the ducting, specifically a failure to sufficiently duct the furnace at the RV factory or in some cases ducting that has become damaged or clogged for one reason or another. This problem was causing my furnace burner cycle on and off excessively, sending it toward an early grave, or at least a premature repair and one that should not be unnecessary.
It appears my RV was “under-ducted” to coin a phrase, that Arctic Fox did not installsufficient ducting so that the furnace could properly expel the hot air it makes. I don’t see why everyone else with the same make and model RV as mine wouldn’t be experiencing the same problem and I know for a fact that other makes and models have had the issue as well. The insidious thing about all this is that you may have the problem and never know it. You may even wind up paying for repeated repairs to your furnace that should not have been necessary, and still never know what caused the problems.
I noticed that when I would turn on my RV furnace the fan would start to run first, then, a few seconds later I could hear the gas burner turn on. That’s as it should be. You may have to be close to your furnace and listen to it carefully in order to hear the burner ignite and burn. What should happen after that is that when the RV reaches the temperature you’ve set on the thermostat the burner should shut off and the fan should keep running another minute or two until the furnace has had a chance to cool down somewhat. Then the fan should shut off.
That’s not what was happening in my RV. Instead, after running a few minutes, and before the RV had reached the temperature set on the thermostat, I could hear the burner shut off. The fan would keep running. Then in a minute or so the burner would start up again. This cycle would repeat every few minutes–burner on, burner off, burner on, burner off, all the while the fan kept running.
Here is what was happening: the fan and burner would start as they should, but because there wasn’t adequate ducting for the furnace to expel the heated air into the RV the heat would back up in the furnace and the burner would overheat. This tripped a safety mechanism, the high temperature limit switch, that would shut off the burner until the fan cooled the burner down to a safe temperature when the burner would then reignite. The furnace was working perfectly but the safety mechanism, the high temperature limit switch that shuts of the burner when it overheats isn’t designed and built for frequent cycling. It was headed for a premature death. Insufficient ducting was restricting the hot air flow out of the furnace causing the safety mechanism to repeatedly activate, sending my furnace hurtling toward the repair shop prematurely.
My furnace was almost certainly behaving like this for a long time before I ever noticed it. Probably since the RV was brand new. Why would I suspect anything was wrong? After all, when it got cold in the RV and I turned on the heat the furnace would in fact heat the RV, but I never noticed the on-again-off-again cycling of the burner because the fan kept running all the while, or if I did notice the burner turning on and off I never thought anything of it. As far as I knew everything seemed to be working just fine… but it wasn’t.
When my RV furnace comes on the fan starts running and then the burner ignites. If things are working as they should the burner will stay lit until the RV reaches the temperature set on the thermostat. Then the burner will shut off and a minute or two later when the furnace has cooled off a little the fan will also shut off. When the burner cycles on and off repeatedly every few minutes it’s a sign that something is wrong. There is a good chance there is a blocked vent or duct, or the manufacturer of the RV did not build in sufficient ducting to allow the furnace to properly breathe. Don’t think your RV manufacturer is above that!
To confirm the on-again-off-again activity of my furnace burner I put my digital meat thermometer’s probe over the floor register of the heating system nearest the furnace. When the temperature rose to about 175º I could hear the high temp limit switch trip and the burner shut off. I watched the thermometer fall to about 140º and I could hear the switch activate, the burner ignite, and I watched the thermometer rise back to about 175º. This cycle repeated over and over until the RV finally reached the temperature set on the thermostat and the burner then fan finally shut off. That ain’t supposed to happen. The burner shouldn’t cycle on and off repeatedly. It should go on once and stay lit until the RV comes to temp and then it should shut off. Once on, once off. That’s all.
I spoke with a tech at Suburban, the maker of my furnace. After explaining the repeated cycling of the furnace burner and the high and low temperatures it was bouncing back and forth between I was told my furnace safety mechanism was working as it should. I was also told that the on-again-off-again action of the burner likely pointed to a restriction in the ducting and that under-ducting by RV manufacturers was a problem Suburban had encountered before.
I understand that my Suburban SF-35FQ furnace has the equivalent of 11 outlets: seven 4″ round outlets on the sides and one large rectangular outlet on the bottom that counts as four round ones. The specs for my furnace say that a minimum of four of the outlets must be used so that the furnace can properly aspirate but the tech told me using more than four is better. In my RV the manufacturer used only the rectangular outlet on the bottom of the furnace which would count as four round ones and this would meet the minimum requirement, but, they also put some 90º bends in the ducting which creates resistance in the airflow within the ducting and it appears that it effectively reduced the airflow to below the minimum requirement thereby causing my furnace to overheat and the safety mechanism to cycle the burner on and off excessively. The installation manual says “Avoid making any sharp turns in the duct system. Sharp turns will increase the static pressure in the plenum area and could cause the furnace to cycle.” That seems to be exactly what was going on in my RV. It would seem my RV was under-ducted at the factory. Thank you Arctic Fox.
You could be having this same problem and it could be going on unbeknownst to you. It’s an under-the-radar kind of thing. I don’t say this so as to create a panic, but it would be worth paying attention to your furnace. You could test it by letting it run for 20 or 30 minutes while listening carefully to see if you can hear the burner turning on and off. If it does not it’s likely fine at least in regard to an overheating burner, that is, assuming your high temperature limit mechanism is functioning properly. If your burner does cycle on and off repeatedly then you may have a blockage in the ducting or your RV manufacturer may have failed to provide sufficient ducting for your furnace. Restrictions in the ducting, by the way, can be caused by insects, critter nests, damaged ducting or the build-up of crud over time. Your furnace would be more likely to experience the problem I have outlined on a warmer day when the air it breathes into its combustion chamber isn’t as cold as it might otherwise be. When it is breathing colder air this works against the burner overheating.
I solved the frequent cycling of my RV furnace by adding another duct. I removed one of the 4″ knockouts on the left side of the furnace and ran some flexible ducting to a register nearby. I can feel a strong airflow coming out of the new register and I tested my heater by letting it run 20-30 minutes and it didn’t cycle on and off at all. Not once. Problem solved.
Should you undertake a similar repair make sure to follow the furnace manufacturer’s instructions or hire it done by a qualified shop or individual. (Good luck with that!) Also be certain the ducting you get is up to the task. Not all of the flexible ducting on the market is suitable for the temperatures encountered in a heating system such as those you find in RVs.
Cutting the hole into which the new register would fit took a bit of figuring. I didn’t want to try to use a keyhole saw because I thought it would be too hard to control and may splinter the surface of the soft luan wood. I couldn’t remove the panel I was cutting into so that ruled out a coping saw. I might have been able to use a 4″ hole saw but that might have splintered the surface and would have been an expense. As it turned out there is a bit that looks like an ordinary drill bit but it’s made to be used like a router bit. (See my reply to John in the Comments section for more information about cutting bits.) You drill a hole into the surface you are cutting with the tip of the bit then move your drill sideways using the side of the bit to cut. I already had Black and Decker RTX rotary tool like a Dremel tool and it came with one of those bits.
Below is a list of the things I used to install the new duct and register The links have my Amazon Affiliate code embedded so if you buy any of these things through the links I provide I may receive a small commission. These items appear in the photos above. Click on any photo to enlarge it.
ThermoPro Food Thermometer
Inexpensive but fast reading and quite accurate. It allowed me to watch the rise and fall of the temperature of the air coming out of our heat ducts in real time, up and down between 140º and 175º, back and forth, over and over.
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The Wave, Coyote Buttes North, Paria Canyon-Vermillion Cliffs Wilderness
It began 190 million years ago during the Jurassic period when dinosaurs roamed the earth. In the heart of what is now known as the Paria Canyon-Vermillion Cliffs Wilderness area that spans the border of Utah and Arizona an unusual and stunning rock formation began to take shape. Layers of windblown desert sands solidified and later eroded to create what is now one of the most spectacular, picturesque examples of crossbedding in Navajo Sandstone that people come from around the world to visit and behold: The Wave. [READ MORE…]
My, how time flies. My last post was apparently made way back on August 7, 2019. Thats a few days more than 2 months ago but it seems like a million years! In that post I wrote about our travels to the Lake Tahoe area, Grand Canyon and Bryce National Parks (NP). Since then, where have we been? I mean where have we been… who can remember??? I’ll try… [READ MORE…]
In June of 2018 Diane and I set off on a west coast to east coast cross country round trip. We couldn’t stay in some places as long as we would have liked because we had a wedding to attend on the east coast. On the return leg of the trip we also felt a little rushed because there were some things I wanted to attend to within a certain time frame out west. All told that trip was 7 months long. I know it may be hard to imagine that someone could feel hurried taking 7 months to get across the country and back, but hey, there’s a lot to see and do in this country–it could easily take 7 years to make the trip if you ask me.
At the beginning of last month we set out on another trip. Before we did we decided we would spend more time camping and less time driving than our previous trip. So far its been that way. On our first day of travel we drove from the San Francisco bay area into the Sierra Nevada mountains where camped for something like 11 nights at Alpine Meadows campground in Truckee, CA.
Originally we had hoped to travel south from Truckee along US 395 boondocking for a couple or three weeks in the shadow of the eastern slope of the Sierra. The view of the mountains to the west is pretty spectacular along 395. It’s best where the mountains are highest–the Sierra Nevada peaks get higher the further south you travel until they reach Mount Whitney which at 14,505′ is the highest mountain in the contiguous 48, then they rather abruptly fall away.
We had to skip our boondocking plans along 395 because they weather was too hot. Originally we had planned to hit the road a couple months earlier in which case the weather would have been just fine but life got in the way and we were delayed. A little factoid of interest, BTW, is that while Mt. Whitney at 14,505′ is the highest place in the lower 48, Badwater in nearby Death Valley is the lowest at 282′ below sea level and it’s possible to drive from Badwater to Whitney Portal in the same day. Whitney Portal is not the top of the mountain but rather where you can begin the climb to the summit some 6,000′ above.
Although we skipped our boondocking plans we spent one night in the Crowley Lake area and 3 more in Lone Pine in order to visit Manzanar, the WWII Japanese internment camp and Mobius Arch along Movie Road in the Alabama Hills.
From there we hightailed it to Ten-X campground in the forest just outside Tusayan, AZ by Grand Canyon National park where we parked ourselves for 12 days. Another nice, long stay… long for us, anyway.
Our next destination, Bryce National Park in Utah. We had hoped to visit the other amazing National Parks in southern Utah–Zion, Canyonlands, Arches, and Capitol Reef–but again, due to our late start it’s too hot to visit any but Bryce which is cooler due to its elevation.
Along the way we passed through the Kanab area, Utah, where we had a serendipitous encounter with artist Patti Lewis who was painting a mural on the side of a building in town where she as adorned a number of others in similar fashion.
As I write we are happily boondocked in a terrific location in the Dixie National Forest. Our nearest neighbors are at least a few hundred feet away. We’re in a ponderosa pine forest. It’s quiet, and lovely, and free. We’re about 20 minutes from Bryce. Yesterday we made a day trip to Cedar Breaks National Monument where we went on a short hike and reveled in the beauty of the wildflower bloom there which is at its peak. We expect to spend about 14 days camped here, another nice long stay, before heading north to the mountains in Idaho, but we’ll see.
This campground is situated about half way between Truckee and Lake Tahoe in the Sierra Nevada mountains in California. This would make for great mountain weather in the summer and winter sports in the winter but the campground is only open from May 15 to Oct. 15, so you’ll have to settle for the great weather 🙂 The area has beautiful scenery, an abundance of hiking and mountain biking, and a great deal of history. At $10 a night for people with interagency passes ($20 otherwise) it’s an easy place to stay the 14 day limit [READ MORE…]
This article is about setting things up to RV with bicycles on board. There may be more involved than you would at first think.
We’ve all seen cars, trucks and RVs traveling down the road with bicycles on the back. The bikes are generally either hanging from or resting upon a bicycle carrier. It should be easy enough to set things up in order to bring our bikes along with your RV, right? Umm… maybe not! RVers may have more things to consider than somebody throwing their bikes on the back of their car for an afternoon outing. [READ MORE…]