Question:

 My question is:  is all this purging of the blower really necessary if the furnace is used once or twice every day?  Or is it only necessary if the furnace has not been used for a longer time than this? Can someone give me some first-hand advice on this?

Answer, NO. Vince Wirth http://home.earthlink.net/~vincewirth

Response:

The best option if you boondock a lot is to shut off the furnace and buy a catalytic heater.

Just beware of the Oxygen requirements of this type heater and the fact that they do produce CO. I have a 30′ fth.  We boondocks at motorcycle races quite often.  I found that 2-13" batteries allowes me to get 2 nights of heater operation as well as the 13" TV and sat system.   We have a young child so running heat is kind of "required" Will Rosenberry KB3CSC

Response:

If below freezing, you still need to consider keeping your tanks warm.  This of course depend on how far below freezing, how long, and whether tanks are covered, insulated, and/or heated. Ron Bowser – Hide quoted text — Show quoted text – snip We do a lot of boondocking so, not wanting to have the blower cycling all night drawing down the batteries, our usual routine on chilly evenings would be to use the furnace until going to bed; then turn the furnace off for the night.  In the morning we would run the furnace through one cycle to take the chill off, then shut it down for the day. The best option if you boondock a lot is to shut off the furnace and buy a catalytic heater.  It uses no electric and all the heat produced is inside the RV.  Not pumped out the exhaust like the furnace.   We are major boondockers and I cannot remember the last time we used the furnace.  Too inefficient and too noisy. Ours has kept us warm enough (34 foot motor home) in below freezing temperatures many times.

Response:

If below freezing, you still need to consider keeping your tanks warm.  This of course depend on how far below freezing, how long, and whether tanks are covered, insulated, and/or heated.

Ron’s point is well taken.  Still, if "below freezing" means in the teens (10-20F) you should be ok.  I’ve camped in that range with both the forced air furnace and with the catalytic heater and there was sufficient propane vapor pressure to operate either. The forced air furnace was definitely a problem.  Especially with the batteries mounted on the trailer tongue where they got cold. The thermostat only went down to 50F – couldn’t be set colder than that. It only took 2 nights to drain the batteries dry, even with some solar recharging of the batteries.  THis was a pair of 6 volt golf cart batteries rated for 220 amp-hours. On the other hand, the idea in the original post of shutting the furnace off will produce a pretty cold RV come morning.  Remember that even if it’s well insulated, as ours is (R11 in the walls and R22 in the ceiling) it’s a relatively small heat sink compared to a house. I’d not be surprised to find the interior temperature below freezing come the dawn and at that point you can have trouble with burst water pipes. On yet another hand, with a catalytic heater you’ll stay nice and warm throughout the night and won’t drain the batteries at all. My only fault with mine is that even though it’s the smallest model that Olympian makes, it still keeps the (24′ length overall, 20 foot coach) trailer way too warm unless the outside temperature is below 50F. I understand that it’s possible to find catalytic heaters with auto-ignition and thermostats but have been unable to locate one.  Ours is a simple model which you light off and then set the fuel knob – no thermostatic capability. Barry – Hide quoted text — Show quoted text -Ron Bowser snip We do a lot of boondocking so, not wanting to have the blower cycling all night drawing down the batteries, our usual routine on chilly evenings would be to use the furnace until going to bed; then turn the furnace off for the night.  In the morning we would run the furnace through one cycle to take the chill off, then shut it down for the day. The best option if you boondock a lot is to shut off the furnace and buy a catalytic heater.  It uses no electric and all the heat produced is inside the RV.  Not pumped out the exhaust like the furnace.   We are major boondockers and I cannot remember the last time we used the furnace.  Too inefficient and too noisy. Ours has kept us warm enough (34 foot motor home) in below freezing temperatures many times.

– Barry Sherman               |   Art does not reproduce what we see. Suma Technologies, LLC      |   It makes us see. — Paul Klee My opinions, not Suma’s     |  

Response:

The forced air furnace was definitely a problem.  Especially with the batteries mounted on the trailer tongue where they got cold. The thermostat only went down to 50F – couldn’t be set colder than that. It only took 2 nights to drain the batteries dry, even with some solar recharging of the batteries.  THis was a pair of 6 volt golf cart batteries rated for 220 amp-hours.

Speaking of thermostats, anyone seen one that can be set below forty.  My rig is always ready to go in the winter and I have to turn on the heater occasionally to make sure it doesn’t get below freezing.  I have thought of adding another one for such occasions and detuning it to go much lower; or to trying to splice in one of the AC switches that turn on at 36 and off at 40 (actually use it as a switch in the DC circuit). I ran into Barry’s problem with the batteries one winter when we were without power for 80 hours and temps didn’t get above freezing (I also watched a little TV).  I had to hook-up the truck a few times to boost the batteries.  A lower thermostat setting would have been an asset. Regarding catalytic heaters, I plan to go for one when I upgrade my rig.   Sounds like the way to go and you don’t have the fan noise. Ron

Response:

Your question on thermostats: Yes, there are several differant stats that may be adjusted to lower levels.  These are not household mercury bulb or bi-metal snap switch types that look good on the wall but commercial heating/refrigeration stats.  They dont look that bad and will work for more years than you will need them.  Go to your local HVAC dealer and ask him for a single pole double throw stat in the heat range you need.  Describe what you want to do and for well under $50.00 he will fix you up. Mike

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I’ve just purchased a newer RV.  In my old one there was a LP gas shutoff valve on the furnace fuel delivery line, accessible from inside the coach. <<snip  My question is:  is all this purging of the blower really necessary if the furnace is used once or twice every day?  Or is it only necessary if the furnace has not been used for a longer time than this? Can someone give me some first-hand advice on this?

Brian,         The new furnaces have no shut off valve because they have dual solenoid valves (also called redundant). IOW, if one leaks, the other will provide backup. Newer furnaces also have a purge cycle built in before ignition  (that annoying 30-45 seconds of cold air at the start of the cycle).         What I’m getting to, is just use the thermostat to control the furnace, and other than the initial firing after a long storage period (if it makes you feel better), don’t bother with the manual purge. — Chris Bryant Bryant R.V.

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valve for the furnace.  According to the manual I must carry out this same procedure by shutting off/turning on the gas at the main control valve on the LP tank.

I haven’t had a problem in the last very many years of motorhoming leaving the gas on all the time.  Seems like you don’t really need a thermostat that would turn the thing on when it got cold, eh?  If it has a thermostat that turns it on as well as off … then either the thermostat or the manual is wrong, eh? Steve

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I’ve just purchased a newer RV.  In my old one there was a LP gas shutoff valve on the furnace fuel delivery line, accessible from inside the coach. The startup procedure I followed was according to the Suburban furnace manual: shut off the gas supply; set the furnace off/on switch to on; set the thermostat above coach temperature; let the blower come on and run for 5 minutes; turn the thermostat down and wait for the blower to stop; turn on the gas and set the thermostat to desired temperature; furnace is now operational  When finished with furnace: turn thermostat down; set switch to off; shut off gas. We do a lot of boondocking so, not wanting to have the blower cycling all night drawing down the batteries, our usual routine on chilly evenings would be to use the furnace until going to bed; then turn the furnace off for the night.  In the morning we would run the furnace through one cycle to take the chill off, then shut it down for the day. While the gas valve on/off and the five minute blower purge was somewhat of a nuisance at least the valve being available inside the coach made the routine tolerable.  My new RV however, does not have a separate on/off valve for the furnace.  According to the manual I must carry out this same procedure by shutting off/turning on the gas at the main control valve on the LP tank. I am not looking forward to the prospect of jumping in and out of the coach every evening and morning to run a few cycles of the furnace.  My question is:  is all this purging of the blower really necessary if the furnace is used once or twice every day?  Or is it only necessary if the furnace has not been used for a longer time than this? Can someone give me some first-hand advice on this?

Response:

Question:

Hand-held hair dryers are good for defrosting frozen spots… – Hide quoted text — Show quoted text – (Bob   Heading for late fall tour through US northwest, British Columbia.  Have heard that it will freeze, so be ready.  No problem, have a good furnace (in Prowler travel trailer), plenty of warm clothes.  But dawned on me — don’t want busted water lines, etc. due to freezing temperatures. What’s the margin?  Short snap shouldn’t bother, how short and how cold   does it have to get before I get nervous.  Don’t know what I’d do about   it while on the road, but it would be nice to NOT worry if I don’t have   to. Any experience?   For this time of year, you should have very little problem.  I do most   of my traveling in the winter in the Pacific Northwest.  Often get in   the high 20s F, and have been in 21 once and 18 once.  But, nothing   prolonged (just weekend trips).  I am sure there are others on this   group that can better speak to really cold. My trailer is an old ‘67 Shasta, 17′ with pressure fresh water tank,   black water tank, and radiant heat, gas light and one 12v dome light. My first experience was in the fall when I did not expect it to freeze   and I had full hookup.  Got just a little below freezing overnight, and   I had no water the next morning (hose froze).  Switched to internal   water and heated some to thaw the water and sewer hose.  The outside   hoses will freeze after a few hours. Down to 21 we seemed to do fine as long as I kept the interior warm and   I opened cabnets where water pipes ran.  Did not do sewer or water   hookup. Worst case was 18.  Did not expect freezing at all, so had full hookups.   Our water line runs in the floor beneath the door area from the tank to   the sink.  We lost internal water that night and I think the door area   was where it froze (luckily did not break).  I now carry some bottled   water.  In disconnecting, I had to heat the fittings to get them off.   Threw the water hose in the back of the truck.  Tried stuffing the sewer   hose in its bumper container and broke it. I put RV anitfreeze in the black water tank and have had no problems   that I know of (but it may have frozen).  I use RV antifreeze for   environmental reasons.  Some use a non-alcohol base anti-freeze (I think   alcohol can desolve some plumbing seals).  I have heard some say put   rock salt in your tanks. My trailer is always ready to go at home, so I run an electric heater to   keep the interior in the upper 30s.  We usually don’t get in the lower   20s in the Seattle area, but occasionally do hit the teens. Bottom line for a trip up here in the fall.  As long as all your water   lines are inside, there should be enough interior heat radiation (even   into storage areas) to withstand high 20s as long as the interior is   well above freezing.  Don’t leave water and sewer lines out below   freezing; but if you do, don’t force a bend until thawed.  You may have   to pour hot water on fittings to disconnect.  I doubt that your holding   tanks would freeze (might get slushy); but you could put rock salt in   them if in doubt.  If you dry camp, I would watch power consumption.   You don’t want to lose your fan. I doubt that you will get below freezing during the day, unless you are   up in the mountains; then not often. Ron Bowser, Seattle Area http://www.eskimo.com/~samoyed/ or go direct to my sub-pages http://www.eskimo.com/~samoyed/maps/    Trip Planning Programs http://www.eskimo.com/~samoyed/iwpa/    Working Dogs – Weight Pull

– The common idea that success spoils people by making them main, egotistic and self-complacent is erroneous; on the contrary, it makes them for the most part, humble, tolerant and kind.  Failure makes people cruel and bitter.                  –Somerset Maugham (1874-1965)

Response:

Here’s a related question:  I’m thinking of doing my annual "go see what southern Utah looks like with snow on it" trip in the Bounder this year.   By the way, historically this trip has involved either no snow or it’s snowing so hard or so overcast and foggy that I can’t see southern Utah! In any case, it’s a ‘96 32H.  Has insulated basement compartments and it looks like I’ve got heating ductwork running near the various tanks.   Can I survive down to, say, 10 degrees with no modifications?  Will it be comfortable?  Will stuff freeze up?  If I need mods, what are the minimal mods to make this work out.  Is the furnace likely to be able to cope with this.  Etc. Etc. Etc.  you get the idea. Thanks… Tom in 104 degree Phoenix

Response:

Heading for late fall tour through US northwest, British Columbia.  Have heard that it will freeze, so be ready.  No problem, have a good furnace (in Prowler travel trailer), plenty of warm clothes.  But dawned on me — don’t want busted water lines, etc. due to freezing temperatures. What’s the margin?  Short snap shouldn’t bother, how short and how cold does it have to get before I get nervous.  Don’t know what I’d do about it while on the road, but it would be nice to NOT worry if I don’t have to. Any experience?  

For this time of year, you should have very little problem.  I do most of my traveling in the winter in the Pacific Northwest.  Often get in the high 20s F, and have been in 21 once and 18 once.  But, nothing prolonged (just weekend trips).  I am sure there are others on this group that can better speak to really cold. My trailer is an old ‘67 Shasta, 17′ with pressure fresh water tank, black water tank, and radiant heat, gas light and one 12v dome light. My first experience was in the fall when I did not expect it to freeze and I had full hookup.  Got just a little below freezing overnight, and I had no water the next morning (hose froze).  Switched to internal water and heated some to thaw the water and sewer hose.  The outside hoses will freeze after a few hours. Down to 21 we seemed to do fine as long as I kept the interior warm and I opened cabnets where water pipes ran.  Did not do sewer or water hookup. Worst case was 18.  Did not expect freezing at all, so had full hookups.  Our water line runs in the floor beneath the door area from the tank to the sink.  We lost internal water that night and I think the door area was where it froze (luckily did not break).  I now carry some bottled water.  In disconnecting, I had to heat the fittings to get them off.   Threw the water hose in the back of the truck.  Tried stuffing the sewer hose in its bumper container and broke it. I put RV anitfreeze in the black water tank and have had no problems that I know of (but it may have frozen).  I use RV antifreeze for environmental reasons.  Some use a non-alcohol base anti-freeze (I think alcohol can desolve some plumbing seals).  I have heard some say put rock salt in your tanks. My trailer is always ready to go at home, so I run an electric heater to keep the interior in the upper 30s.  We usually don’t get in the lower 20s in the Seattle area, but occasionally do hit the teens. Bottom line for a trip up here in the fall.  As long as all your water lines are inside, there should be enough interior heat radiation (even into storage areas) to withstand high 20s as long as the interior is well above freezing.  Don’t leave water and sewer lines out below freezing; but if you do, don’t force a bend until thawed.  You may have to pour hot water on fittings to disconnect.  I doubt that your holding tanks would freeze (might get slushy); but you could put rock salt in them if in doubt.  If you dry camp, I would watch power consumption.   You don’t want to lose your fan. I doubt that you will get below freezing during the day, unless you are up in the mountains; then not often. Ron Bowser, Seattle Area http://www.eskimo.com/~samoyed/     or go direct to my sub-pages http://www.eskimo.com/~samoyed/maps/    Trip Planning Programs http://www.eskimo.com/~samoyed/iwpa/    Working Dogs – Weight Pull

Response:

The Moellers write extensively about cold weather Rving in their book on fulltiming.  One hint I remember is that you should leave cupboard doors open during the night so your heater is likely to reach some of the pipes. Heading for late fall tour through US northwest, British Columbia.  Have   heard that it will freeze, so be ready.  No problem, have a good furnace   (in Prowler travel trailer), plenty of warm clothes.  But dawned on me — don’t want busted water lines, etc. due to freezing temperatures. What’s the margin?  Short snap shouldn’t bother, how short and how cold   does it have to get before I get nervous.  Don’t know what I’d do about   it while on the road, but it would be nice to NOT worry if I don’t have   to. Any experience?  

– The common idea that success spoils people by making them main, egotistic and self-complacent is erroneous; on the contrary, it makes them for the most part, humble, tolerant and kind.  Failure makes people cruel and bitter.                  –Somerset Maugham (1874-1965)

Response:

Here’s a related question:  I’m thinking of doing my annual "go see what southern Utah looks like with snow on it" trip in the Bounder this year.   By the way, historically this trip has involved either no snow or it’s snowing so hard or so overcast and foggy that I can’t see southern Utah! In any case, it’s a ‘96 32H.  Has insulated basement compartments and it looks like I’ve got heating ductwork running near the various tanks.   Can I survive down to, say, 10 degrees with no modifications?  Will it be comfortable?  Will stuff freeze up?  If I need mods, what are the minimal mods to make this work out.  Is the furnace likely to be able to cope with this.  Etc. Etc. Etc.  you get the idea. Thanks… Tom in 104 degree Phoenix

I just got my 96 28′ Bounder in April, so I haven’t had a chance to do any winter camping yet. However I have used my 2 previous motorhomes in the winter for some 12 years, at temperatures as low as -25 degrees. The Bounder was chosen in large part because it was set up better for cold weather camping than any other MHs I saw that were in my price range. Nevertheless, it is far from perfect in that regard. I believe that down to 20 degress, maybe just a bit lower, you should have no problems. Below that, I think a few areas will need to be addressed. 1. On my 28′ there is no provision to supply heat to the lines on the rear of the water heater. They will receive some radiated heat from the tank (when it is on, of course) but at colder temps this will not be adequate. 2. The water tank outlet hose runs very close to the baggage door on the right side, and then runs between the tank and a bulkhead, across the MH to the pump on the right side. I think your 32′ is set up the same. I suspect this line will freeze up pretty easily. I am not sure what I will do about this yet. The easiest solution would be to simply install a heat tape on the line. (I have an inverter installed that could operate the heat tape when on the road or without shore power). However, I suspect that below maybe 10 degrees, the water in the lower part of the tank might freeze. 3. I have doubts about the lines going to the shower valve in the basement. I haven’t taken this apart yet, but it appears that they will not get enough heat (if any). 4.The plastic panel under the holding tank valves will let a lot of cold into that area. This will be easy to correct by making an insulated (foam) panel with some weatherstripping to replace the plastic panel for winter use. I think the key to improving the cold weather usability of the Bounder lies in improving the air circulation through the basement. I think that all of the heat output from the furnace should go to the interior of the motorhome ( my MH has one duct going into the basement). Then the return air should go through vents in the floor at the extremities of the basement (heated) area, and then on back to the furnace. This is what I intend to do. By putting a return grille in the floor directly above the rear of the water heater, I think I can create enough airflow to eliminate freezing in that area. The main return grille (under the wardrobe in my 28" would be blocked off, forcing all of the return air to go through the basement. You have to just locate the return registers strategically, and make sure you provide enough return area (this is important, and the area will be specified in the furnace manual) I suspect that at 10 degrees, your furnace will be running 80 to 90% of the time. Without shore power your batteries will run down quickly. Your best friends in cold weather camping are shore power and a couple of small electric heaters! Hope my ramblings help somewhat. I too would love to hear from Bounder owners with real winter experience. BTW, I will be on the road from 8-9 thru 8-18. Don’t have to worry about freez-ups now!                 Tom Thomas    He who dies with the most toys wins! LEGO: MT++++1c(5590)TR+++2(4558)TO+++3(6399)

Response:

Heading for late fall tour through US northwest, British Columbia.  Have heard that it will freeze, so be ready.  No problem, have a good furnace (in Prowler travel trailer), plenty of warm clothes.  But dawned on me — don’t want busted water lines, etc. due to freezing temperatures. What’s the margin?  Short snap shouldn’t bother, how short and how cold does it have to get before I get nervous.  Don’t know what I’d do about it while on the road, but it would be nice to NOT worry if I don’t have to. Any experience?  

Response: