Newb question about furnace

[bchesley]

I am assuming that it will be ok to run the furnace while in tow? My scenario is what do you do if you are entering freezing temps with an unwinterized trailer to camp? If the fridge is ok to use while in tow then the furnace should be too right? Thanks

[GaryWT]

Interesting question. The 2 appliances are made differently so I am not sure. The gas would shut down I believe if the flame went out. How long will you be driving in freezing temps and how cold is it expected.

[chuckster57]

The flame for the refer is in a protected flue. The heater is vented directly to the exterior.

I would think as you drive, the air flow over the vents may disturb the flame enough to cause a shutdown.

Interesting question. If your going to occupy the unit as soon as you get to the CG, I don't think freezing would be an issue.

[12 er]

They way I have been told it is against the law to tow and have your propane on. With that said, I have towed with my propane tank on so the refigerator would keep the food cold. I have talked to other people who tow with it on and if you think about it there are vehicles that are powered by propane. We just bought a new trailer in September and I did not tow with the propane on and by the time we go to where we were going things in the freezer had started to thaw out and the milk and the pop was not that cold. So I think I will continue to leave it on while I travel.

[chuckster57]

Since the 9/11 event I believe there are a couple of places where your propane must be turned off. Your directed to pull off the road and they are checked, but I haven't seen any place out west where that's the case. I travel with my propane on and refer operating, but nothing else.

[Javi]

I am assuming that it will be ok to run the furnace while in tow? My scenario is what do you do if you are entering freezing temps with an unwinterized trailer to camp? If the fridge is ok to use while in tow then the furnace should be too right? Thanks

Other than the fact that the flame might blow out while towing, I can think of another even bigger problem.... the vents for the heater may well be covered by the slides in which case the back pressure might also cause the heater to over heat and shut off.

[JRTJH]

There are some places where propane tanks must be turned off and some places where tanks larger than 20 pounds are not allowed. Some of the "back east" tunnels come to mind. Like Chuckster57 said, I haven't seen any in the western part of the US.

As for the manufacturer's recommendations about operating the refrigerator and furnace while towing, here is what's in the operator's manuals.

Dometic does not specifically say that their refrigerators are "legal to operate while towing" (probably because of the tunnel restrictions, etc) but this statement is in the manual, indicating that the refrigerator is designed to operate with the "pitching and rolling" of a moving vehicle:

"When the vehicle is moving, the leveling is not critical, as the rolling and pitching movement of the vehicle will pass to either side of level, keeping the liquid ammonia from accumulating in the evaporator tubing."

On the other hand, Suburban specifically recommends against operating their furnaces while the trailer is in motion:
http://www.rvcomfort.com/suburban/service/furnaces_questions.php

"Can I use my furnace while driving?

No. Suburban does not feel this is a safe practice. Some states have laws forbidding the use of propane while driving. You should be sure all gas appliances are off and their ignition systems are off while the vehicle is in motion or being towed."

In discussions with people at campgrounds through the years, I've gathered that most RV'ers travel with their refrigerator operating and do not use their furnace while the trailer is in motion. The majority usually turn off the appliances while refueling, but even that is not an "across the board" consideration by every RV'er.

[chuckster57]

I believe most floor registers are in the center and most likely not covered by a slide. And slides don't ride on the floor when retracted, so there may be enough gap for airflow.

[Javi]

I believe most floor registers are in the center and most likely not covered by a slide. And slides don't ride on the floor when retracted, so there may be enough gap for airflow.

Actually, both my Passport 2890RL and the new Cougar 333MKS had the floor vents partially covered by the carpet on the slide/slides.

[chuckster57]

I can see where that could be the case. My slides have carpet that extends past the slide floor but they don't cover the registers.

[bchesley]

Thanks guys, I think that I am going to condition it before the drive then shut it down for the trip. We are not going to travel more than 6 hours at a time and I think that I should be ok for that duration.

[outwest]

The one time parents tried to tow with heater on, it blew out and was completely futile. I know someone else that said that when she tried it, she ended up with a trucker flagging her down to call her attention to the fact that there were flames coming out the side of her trailer, pulling over with her and helping her to put the fire out with his extinguisher.

As for the fridge, I always tow with it on in gas mode and no problem so far *knock on wood*

[JRTJH]

Thanks guys, I think that I am going to condition it before the drive then shut it down for the trip. We are not going to travel more than 6 hours at a time and I think that I should be ok for that duration.

If it's a new trailer and you haven't run the furnace yet, you'll want to open all the windows and doors, turn the furnace on and let it "do its thing" before you try to use it. The oils and paints used on the furnace during assembly are not really 'nice to smell' and will probably set off the smoke detector during initial use. It takes about an hour to burn all that stuff off the furnace and being "trapped inside" on a cold rainy night isn't the best time to find out.

Check it out thoroughly before your trip.

[chuckster57]

Part of a proper PDI is running the heater. I run it long enough to set off the smoke alarm, two checks at one time.
From reading posts here on this forum, it seems there are lots of dealers that don't bother doing anything prior to delivery.

[Festus2]

If you were thinking of running your furnace while driving so that upon arrival the inside of the RV would be "warm". However, I am wondering how much interior heat loss there will be when you are traveling down the road in "cold" weather at say 60-65 mph. These units aren't particularly well-insulated to begin with - including windows.

I am thinking that a moving RV would be subjected to the same kind of wind chill conditions as if it were standing still and the wind was blowing 60-65 mph. I think the heat loss would be significant and really not worth having the furnace running for that purpose. Why not wait until you reach your destination, then light the furnace and/or a space heater to warm up the interior?

If you are operating the furnace to keep your holding tanks and/or water lines from freezing, any warm air that does manage to find its way into the underbelly would soon be dissipated by the rush of cold air that is sure to find its way into that area as you are driving. There are just too many small openings in the underbelly - unless you have taken steps to ensure that they have all been sealed.

[Bill & Deb]

I am assuming that it will be ok to run the furnace while in tow? My scenario is what do you do if you are entering freezing temps with an unwinterized trailer to camp? If the fridge is ok to use while in tow then the furnace should be too right? Thanks

What I do when travelling south from Ontario in early January, is when I'm at home I run electric heaters till departure. Then every 2-3 hrs when I stop for a pee or stretch break , I run the furnace for about 5 minutes to bring up the inside temperature. This keeps any of the liquids from freezing. If I'm motelling it for the night, I turn the furnace on and warm the trailer up to the mid 70's then turn it off.

I do run the refrigerator while driving but "never" get the trailer near a gas pump or propane filling station.

Bill

[BobnLee]

My 26 SAB slides cover my living room registers, but I have water lines in the front basement (thats where I look to make sure the lines are pink) I know there is no heat going in there even if the furnace is on,Im thinking if you are going into freezing temps (we live in one and it seems year round) I would blow out the lines and drain the low points and fresh water tank. We fully winterize and we leave for Florida sometime either in January or Feb. Just dry camp and use the campground washrooms until we hit Georgia IMHO

[SkiSmuggs]

I have discovered, quite by accident, that any air flow impedance reduces the heat output of my furnace. I noticed it the first time I Walmarted with a recliner right up against the furnace air intake and the air at the ducts was only lukewarm. I also notice while running the furnace with the main slider covering one of the two heat registers that the furnace output was warm, but it puts out plenty of heat with everything unblocked.

[EricLynnAllison]

I accidently left the furnace on and closed up the 5th wheel. Went to use the rv and the furnace wouldn't work. I had to call suburban and they told me about the covered vent tripping the circuit board on the furnace. I had to reset the circuit board per their instructions to get the furnace online again. They warned me that it could damage the furnace if the air flow from the vents is blocked.